Pub Date : 2025-01-08DOI: 10.1016/j.chemphys.2025.112601
Kai Wang, Wenli Zou
Ab initio calculations on the low-lying states of BiX (X = Cl, Br, and I) below 45 000 cm−1 have been performed using the multi-reference configuration interaction and the equation-of-motion coupled-cluster methods with the spin–orbit coupling effects being included perturbatively and variationally, respectively. Totally ten states are found to be bound ones for each molecule, including the ground state , the first excited state , five higher-lying valence excited states (, , , , and ), and three Rydberg states (, , and ) originating from the Bi 7 occupation. The derived spectroscopic constants as well as the estimated radiative lifetimes are overall consistent with the available experimental values. Our results may enhance the understanding on the distribution of electronic states of BiX and provide theoretical references for future spectroscopic observations.
{"title":"Theoretical study of low-lying electronic states of BiCl, BiBr, and BiI","authors":"Kai Wang, Wenli Zou","doi":"10.1016/j.chemphys.2025.112601","DOIUrl":"10.1016/j.chemphys.2025.112601","url":null,"abstract":"<div><div><em>Ab initio</em> calculations on the low-lying <span><math><mi>Ω</mi></math></span> states of BiX (X = Cl, Br, and I) below 45<!--> <!-->000 cm<sup>−1</sup> have been performed using the multi-reference configuration interaction and the equation-of-motion coupled-cluster methods with the spin–orbit coupling effects being included perturbatively and variationally, respectively. Totally ten <span><math><mi>Ω</mi></math></span> states are found to be bound ones for each molecule, including the ground state <span><math><mrow><msub><mrow><mi>X</mi></mrow><mrow><mn>1</mn></mrow></msub><msup><mrow><mn>0</mn></mrow><mrow><mo>+</mo></mrow></msup></mrow></math></span>, the first excited state <span><math><mrow><msub><mrow><mi>X</mi></mrow><mrow><mn>2</mn></mrow></msub><mn>1</mn></mrow></math></span>, five higher-lying valence excited states (<span><math><mrow><mi>a</mi><mn>2</mn></mrow></math></span>, <span><math><mrow><msup><mrow><mi>A</mi></mrow><mrow><mo>′</mo></mrow></msup><msup><mrow><mn>0</mn></mrow><mrow><mo>−</mo></mrow></msup></mrow></math></span>, <span><math><mrow><mi>A</mi><msup><mrow><mn>0</mn></mrow><mrow><mo>+</mo></mrow></msup></mrow></math></span>, <span><math><mrow><msup><mrow><mi>A</mi></mrow><mrow><mo>′</mo><mo>′</mo></mrow></msup><mn>1</mn></mrow></math></span>, and <span><math><mrow><mi>B</mi><msup><mrow><mn>0</mn></mrow><mrow><mo>+</mo></mrow></msup></mrow></math></span>), and three Rydberg states (<span><math><mrow><msub><mrow><mi>C</mi></mrow><mrow><mn>1</mn></mrow></msub><msup><mrow><mn>0</mn></mrow><mrow><mo>−</mo></mrow></msup></mrow></math></span>, <span><math><mrow><msub><mrow><mi>C</mi></mrow><mrow><mn>2</mn></mrow></msub><msup><mrow><mn>0</mn></mrow><mrow><mo>+</mo></mrow></msup></mrow></math></span>, and <span><math><mrow><msub><mrow><mi>C</mi></mrow><mrow><mn>3</mn></mrow></msub><mn>1</mn></mrow></math></span>) originating from the Bi 7<span><math><mi>s</mi></math></span> occupation. The derived spectroscopic constants as well as the estimated radiative lifetimes are overall consistent with the available experimental values. Our results may enhance the understanding on the distribution of electronic states of BiX and provide theoretical references for future spectroscopic observations.</div></div>","PeriodicalId":272,"journal":{"name":"Chemical Physics","volume":"591 ","pages":"Article 112601"},"PeriodicalIF":2.0,"publicationDate":"2025-01-08","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143164919","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"化学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2025-01-08DOI: 10.1016/j.chemphys.2025.112607
Yang Zhu , Qian-Xu Wang , Wei-Cheng Sun , Fang Wang , Hui-Hui Hong , Bin Li , Feng-Lei Qi , Yu-Qing Wang , Yuan-Lai Xie , Chang-Qi Chen , Jin-Xia Liang
In the ultra-high vacuum environment of fusion devices, sorbent materials were required not only to remove H2, but also to capture impurity gases (i.e., H2O, CO2, O2, etc.). The adsorption of gases by sorbent materials was affected by a combination of surface adsorption and bulk diffusion. In this work, the first-principles method was employed to analyze the stability of interstitial sites for H and O atoms in Ti-Zr binary alloy sorbent. Diffusion pathways and barriers for H and O atoms among interstitial sites were calculated using the Climbing Image Nudged Elastic Band method (CI-NEB). The stability of interstitial sites occupied by solute atoms was found to affect the ease of diffusion of solute atoms between adjacent interstitial sites. The higher the stability of these interstitial sites, the more difficult it was for the atom to diffuse to other sites. However, solute atoms were more likely to diffuse from less stable interstitial sites to those with greater stability. The Tb tetrahedral interstitial site in Ti0.5Zr0.5 was most readily occupied by the H atom. The energy barrier for diffusion from the OC octahedral interstitial site to the Tb tetrahedral site was found to be the lowest, which was equal to 0.135 eV. The O atom was most likely to occupy the OC octahedral interstitial sites. When diffusing along the 2Ta3-3Ta3 path parallel to the C-axis, the lowest diffusion barrier for O atom was 5.425 eV. The next most favorable diffusion pathway was from the Ta tetrahedral interstitial site to the OC octahedral site, with a diffusion barrier of 5.435 eV. The main findings of the diffusion mechanism of H and O in the bulk structure of binary titanium-zirconium alloys revealed in this work are expected to provide a theoretical reference and potential feasibility analysis for the application of new titanium-zirconium-based sorbent materials.
{"title":"Diffusion mechanism of H and O at the interstitial sites of a Ti-Zr alloy sorbent: A first-principles investigation","authors":"Yang Zhu , Qian-Xu Wang , Wei-Cheng Sun , Fang Wang , Hui-Hui Hong , Bin Li , Feng-Lei Qi , Yu-Qing Wang , Yuan-Lai Xie , Chang-Qi Chen , Jin-Xia Liang","doi":"10.1016/j.chemphys.2025.112607","DOIUrl":"10.1016/j.chemphys.2025.112607","url":null,"abstract":"<div><div>In the ultra-high vacuum environment of fusion devices, sorbent materials were required not only to remove H<sub>2</sub>, but also to capture impurity gases (i.e., H<sub>2</sub>O, CO<sub>2</sub>, O<sub>2</sub>, etc.). The adsorption of gases by sorbent materials was affected by a combination of surface adsorption and bulk diffusion. In this work, the first-principles method was employed to analyze the stability of interstitial sites for H and O atoms in Ti-Zr binary alloy sorbent. Diffusion pathways and barriers for H and O atoms among interstitial sites were calculated using the Climbing Image Nudged Elastic Band method (CI-NEB). The stability of interstitial sites occupied by solute atoms was found to affect the ease of diffusion of solute atoms between adjacent interstitial sites. The higher the stability of these interstitial sites, the more difficult it was for the atom to diffuse to other sites. However, solute atoms were more likely to diffuse from less stable interstitial sites to those with greater stability. The Tb tetrahedral interstitial site in Ti<sub>0.5</sub>Zr<sub>0.5</sub> was most readily occupied by the H atom. The energy barrier for diffusion from the OC octahedral interstitial site to the Tb tetrahedral site was found to be the lowest, which was equal to 0.135 eV. The O atom was most likely to occupy the OC octahedral interstitial sites. When diffusing along the 2Ta3-3Ta3 path parallel to the C-axis, the lowest diffusion barrier for O atom was 5.425 eV. The next most favorable diffusion pathway was from the Ta tetrahedral interstitial site to the OC octahedral site, with a diffusion barrier of 5.435 eV. The main findings of the diffusion mechanism of H and O in the bulk structure of binary titanium-zirconium alloys revealed in this work are expected to provide a theoretical reference and potential feasibility analysis for the application of new titanium-zirconium-based sorbent materials.</div></div>","PeriodicalId":272,"journal":{"name":"Chemical Physics","volume":"591 ","pages":"Article 112607"},"PeriodicalIF":2.0,"publicationDate":"2025-01-08","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143164917","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"化学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2025-01-07DOI: 10.1016/j.chemphys.2025.112606
Yusong Pan , Shuhuan He , Linjie Ou , Shihui Zang , Run Huang
Photocatalytic technology is one of the most promising technologies for wastewater treatment. In this paper, Ag2S/Ag2CrO4 core–shell heterojunction were prepared using in-situ anion exchange method. The structure, morphology, and optical properties of the prepared samples were characterized by XRD, SEM, TEM, XPS, and DRS technologies. The photo-degradation results verified that the 2 %-Ag2S/Ag2CrO4 heterojunction exhibited excellent photocatalytic activity for degradation of organic dyes and antibiotics under visible light irradiation. The removal efficiency for RhB was 95 % in 15 min, which was obviously superior to that of pure Ag2CrO4 (∼73 %) and Ag2S (∼7%) photocatalysts. The enhanced photocatalytic performance of the Ag2S/Ag2CrO4 was mainly attributed to the Z-scheme core–shell heterojunction structure of the photocatalyst that facilitated excellent charge carriers separation and migration. Meanwhile, the results of trapping experiments for active species demonstrated that both the holes (h+) and superoxide radical (O2−) played an important role for degradation of organic pollutants.
{"title":"In-situ anion exchange preparation of Ag2S/Ag2CrO4 core–shell heterojunction with enhanced visible-light photocatalytic activity","authors":"Yusong Pan , Shuhuan He , Linjie Ou , Shihui Zang , Run Huang","doi":"10.1016/j.chemphys.2025.112606","DOIUrl":"10.1016/j.chemphys.2025.112606","url":null,"abstract":"<div><div>Photocatalytic technology is one of the most promising technologies for wastewater treatment. In this paper, Ag<sub>2</sub>S/Ag<sub>2</sub>CrO<sub>4</sub> core–shell heterojunction were prepared using <em>in-situ</em> anion exchange method. The structure, morphology, and optical properties of the prepared samples were characterized by XRD, SEM, TEM, XPS, and DRS technologies. The photo-degradation results verified that the 2 %-Ag<sub>2</sub>S/Ag<sub>2</sub>CrO<sub>4</sub> heterojunction exhibited excellent photocatalytic activity for degradation of organic dyes and antibiotics under visible light irradiation. The removal efficiency for RhB was 95 % in 15 min, which was obviously superior to that of pure Ag<sub>2</sub>CrO<sub>4</sub> (∼73 %) and Ag<sub>2</sub>S (∼7%) photocatalysts. The enhanced photocatalytic performance of the Ag<sub>2</sub>S/Ag<sub>2</sub>CrO<sub>4</sub> was mainly attributed to the Z-scheme core–shell heterojunction structure of the photocatalyst that facilitated excellent charge carriers separation and migration. Meanwhile, the results of trapping experiments for active species demonstrated that both the holes (h<sup>+</sup>) and superoxide radical (<img>O<sub>2</sub><sup>−</sup>) played an important role for degradation of organic pollutants.</div></div>","PeriodicalId":272,"journal":{"name":"Chemical Physics","volume":"591 ","pages":"Article 112606"},"PeriodicalIF":2.0,"publicationDate":"2025-01-07","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143164920","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"化学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2025-01-06DOI: 10.1016/j.chemphys.2024.112599
Boning Yan, Kang Xu, Ming Lei
This article takes the representative ternary and quaternary polycyclic aromatic amines (PAAs) isomers such as phenanthamine and pyreneamine as examples, and uses the Clar’s aromatic π-sextet rule combined with nucleus independent chemical shift (NICS) criteria and structural and electronic indices (such as HOMA, MCBO and MCI), to study their structure–reactivity relationship in electrochemical radical reactions based on the experimental results. By analyzing and discussing the changes in aromaticity and bond length of various ring systems in the structures of the substrates, radical intermediates, and products, as well as radical stability, we have gained a deeper understanding of the reaction mechanism and regioselectivity for construction of large π-conjugated frameworks of nitrogen fused helicenes and functional polymers through electrochemical tandem reactions of PAAs. In general, resonant structures containing more Clar’s aromatic π-sextet in the structure have higher stability, which determines the reaction pathway and types of the product. In this study, Clar’s rule, NICS criteria, HOMA, MCBO and MCI mutually supported and validated each other well, demonstrated that the combination of Clar’s rule and NICS criteria may be a beneficial tool for analyzing and predicting the reactivity of PAH derivatives and the structure of complex polycyclic aromatic products, moreover, expanding their application to non-planar heteroatom doped helicenes beyond PAH compounds.
{"title":"Insights into the electrochemical radical reaction of polycyclic aromatic amines from Clar’s aromatic π-sextet rule and NICS criteria","authors":"Boning Yan, Kang Xu, Ming Lei","doi":"10.1016/j.chemphys.2024.112599","DOIUrl":"10.1016/j.chemphys.2024.112599","url":null,"abstract":"<div><div>This article takes the representative ternary and quaternary polycyclic aromatic amines (PAAs) isomers such as phenanthamine and pyreneamine as examples, and uses the Clar’s aromatic π-sextet rule combined with nucleus independent chemical shift (NICS) criteria and structural and electronic indices (such as HOMA, MCBO and MCI), to study their structure–reactivity relationship in electrochemical radical reactions based on the experimental results. By analyzing and discussing the changes in aromaticity and bond length of various ring systems in the structures of the substrates, radical intermediates, and products, as well as radical stability, we have gained a deeper understanding of the reaction mechanism and regioselectivity for construction of large π-conjugated frameworks of nitrogen fused helicenes and functional polymers through electrochemical tandem reactions of PAAs. In general, resonant structures containing more Clar’s aromatic π-sextet in the structure have higher stability, which determines the reaction pathway and types of the product. In this study, Clar’s rule, NICS criteria, HOMA, MCBO and MCI mutually supported and validated each other well, demonstrated that the combination of Clar’s rule and NICS criteria may be a beneficial tool for analyzing and predicting the reactivity of PAH derivatives and the structure of complex polycyclic aromatic products, moreover, expanding their application to non-planar heteroatom doped helicenes beyond PAH compounds.</div></div>","PeriodicalId":272,"journal":{"name":"Chemical Physics","volume":"591 ","pages":"Article 112599"},"PeriodicalIF":2.0,"publicationDate":"2025-01-06","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143164923","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"化学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2025-01-06DOI: 10.1016/j.chemphys.2024.112597
Viviane S. Vaiss, Luciano T. Costa
The development of efficient technologies that allow the use of CO as a raw material for the synthesis of high value-added products is extremely important. Electrochemical methods are being considered promising. To assist in the planning of more efficient electrocatalysts, this work investigated, through DFT calculations, the structure and properties of pure MoS and doped with various elements. The results obtained indicate that doping with Nb or Ti elements provides a greater reduction in the work function of MoS. The lower the material’s work function, the higher the reaction current density and the better the material’s performance as an electrocatalyst. Furthermore, the formation energies of the COOH and CHO intermediates in MoS doped with Nb or Ti are more stable than those of the CO intermediate. The high stability of the binding energy of the CO* intermediate in relation to other intermediates represents a limitation for the catalytic efficiency.
{"title":"Theoretical Systematic investigation as a Strategic Tool for the design of more efficient pure and doped MoS2 catalysts for CO2 Electroreduction","authors":"Viviane S. Vaiss, Luciano T. Costa","doi":"10.1016/j.chemphys.2024.112597","DOIUrl":"10.1016/j.chemphys.2024.112597","url":null,"abstract":"<div><div>The development of efficient technologies that allow the use of CO<span><math><msub><mrow></mrow><mrow><mn>2</mn></mrow></msub></math></span> as a raw material for the synthesis of high value-added products is extremely important. Electrochemical methods are being considered promising. To assist in the planning of more efficient electrocatalysts, this work investigated, through DFT calculations, the structure and properties of pure MoS<span><math><msub><mrow></mrow><mrow><mn>2</mn></mrow></msub></math></span> and doped with various elements. The results obtained indicate that doping with Nb or Ti elements provides a greater reduction in the work function of MoS<span><math><msub><mrow></mrow><mrow><mn>2</mn></mrow></msub></math></span>. The lower the material’s work function, the higher the reaction current density and the better the material’s performance as an electrocatalyst. Furthermore, the formation energies of the COOH<span><math><msup><mrow></mrow><mrow><mo>∗</mo></mrow></msup></math></span> and CHO<span><math><msup><mrow></mrow><mrow><mo>∗</mo></mrow></msup></math></span> intermediates in MoS<span><math><msub><mrow></mrow><mrow><mn>2</mn></mrow></msub></math></span> doped with Nb or Ti are more stable than those of the CO<span><math><msup><mrow></mrow><mrow><mo>∗</mo></mrow></msup></math></span> intermediate. The high stability of the binding energy of the CO* intermediate in relation to other intermediates represents a limitation for the catalytic efficiency.</div></div>","PeriodicalId":272,"journal":{"name":"Chemical Physics","volume":"591 ","pages":"Article 112597"},"PeriodicalIF":2.0,"publicationDate":"2025-01-06","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143164858","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"化学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2025-01-06DOI: 10.1016/j.chemphys.2025.112604
Yiwei Feng , Yujie Yan , Hai Xie , Jinxiang Liu
We performed first-principles calculations and simulations to investigate the hydrogen storage properties of binary hydrates formed by H2 and CH4. The results showed that the optimum hydrogen storage capacity ranged from 3.43 wt% to 5.42 wt%, and the high storage capacity could be achieved by tuning cage occupation of CH4 in 512 or 51264 cages. Further, two binary hydrate structures (denoted as T1 and T2) were chosen to assess the effect of pressure and temperature on the hydrate stability. Simulation results showed that two hydrates were stable at the studied conditions (10–30 MPa, and 260–285 K). At high pressures (more than 20 MPa) T1 structure was stable, while at low pressures T2 structure was stable. More importantly, H2 + CH4 binary hydrates exhibit anomalous stability at about 275 K, which would be helpful for the application of hydrate-based hydrogen storage technology under mild conditions.
{"title":"Molecular Insight into hydrogen storage of H2 + CH4 sII hydrates","authors":"Yiwei Feng , Yujie Yan , Hai Xie , Jinxiang Liu","doi":"10.1016/j.chemphys.2025.112604","DOIUrl":"10.1016/j.chemphys.2025.112604","url":null,"abstract":"<div><div>We performed first-principles calculations and simulations to investigate the hydrogen storage properties of binary hydrates formed by H<sub>2</sub> and CH<sub>4</sub>. The results showed that the optimum hydrogen storage capacity ranged from 3.43 wt% to 5.42 wt%, and the high storage capacity could be achieved by tuning cage occupation of CH<sub>4</sub> in 5<sup>12</sup> or 5<sup>12</sup>6<sup>4</sup> cages. Further, two binary hydrate structures (denoted as <strong>T</strong>1 and <strong>T</strong>2) were chosen to assess the effect of pressure and temperature on the hydrate stability. Simulation results showed that two hydrates were stable at the studied conditions (10–30 MPa, and 260–285 K). At high pressures (more than 20 MPa) <strong>T</strong>1 structure was stable, while at low pressures <strong>T</strong>2 structure was stable. More importantly, H<sub>2</sub> + CH<sub>4</sub> binary hydrates exhibit anomalous stability at about 275 K, which would be helpful for the application of hydrate-based hydrogen storage technology under mild conditions.</div></div>","PeriodicalId":272,"journal":{"name":"Chemical Physics","volume":"591 ","pages":"Article 112604"},"PeriodicalIF":2.0,"publicationDate":"2025-01-06","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143164922","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"化学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2025-01-05DOI: 10.1016/j.chemphys.2025.112602
Sakeerali C K , Sung Min Heo , Chang Woo Kim
Cu2O has garnered increased interest due to its ideal band gap and excellent carrier separation efficiency for photo catalysis; nonetheless, charge recombination still causes instability in practical usage. Here we design and fabricate Truncated cube Cu2O(T C)@NH2-MIL-125(Ti) core–shell. The main bonds formed between NH2-MIL-125(Ti) and T C are through the NCuN, NOCu bond and the CuO surface interaction in addition formed. The Truncated cube shape of Cu2O as a core and NH2-MIL-125(Ti) shell with limited recombination is seldom researched. The rate constant (K) for the photocatalytic methylene blue degradation of Cu2O(T C)@NH2-MIL-125(Ti) was 0.0182 min−1, 3.35 times higher than that of pure TC. The closely spaced band structures and close contact surfaces between T C and NH2-MIL-125(Ti) should be the origin of the core–shell’s increased photocatalytic activity, as they facilitate the efficient transfer and separation of the photo-generated charge carriers. Cu2+ proportion to Cu1+ after core–shell preparation is 45.66 %, which causes more oxygen vacancy and charge imbalances, increasing reactant adsorption and light absorption in the visible spectrum. The stability test towards MB employing T C@NH2-MIL-125(Ti) core–shell and the photocatalytic scavenger test have also been studied. Moreover, a Type-II heterojunction was produced by photo-generated electron transfer from T C to NH2-MIL-125(Ti). Such a heterostructure sheds light on Cu2O-related core–shell materials’ exceptionally effective recombination suppression and improved photocatalytic effectiveness.
{"title":"Preparation of core–shell structured Cu2O@NH2-MIL-125(Ti) MOF and efficient photocatalytic degradation of methylene blue","authors":"Sakeerali C K , Sung Min Heo , Chang Woo Kim","doi":"10.1016/j.chemphys.2025.112602","DOIUrl":"10.1016/j.chemphys.2025.112602","url":null,"abstract":"<div><div>Cu<sub>2</sub>O has garnered increased interest due to its ideal band gap and excellent carrier separation efficiency for photo catalysis; nonetheless, charge recombination still causes instability in practical usage. Here we design and fabricate Truncated cube Cu<sub>2</sub>O(T C)@NH<sub>2</sub>-MIL-125(Ti) core–shell. The main bonds formed between NH<sub>2</sub>-MIL-125(Ti) and T C are through the <img>N<img>Cu<img>N<img>, <img>N<img>O<img>Cu<img> bond and the Cu<img>O surface interaction in addition formed. The Truncated cube shape of Cu<sub>2</sub>O as a core and NH<sub>2</sub>-MIL-125(Ti) shell with limited recombination is seldom researched. The rate constant (K) for the photocatalytic methylene blue degradation of Cu<sub>2</sub>O(T C)@NH<sub>2</sub>-MIL-125(Ti) was 0.0182 min<sup>−1</sup>, 3.35 times higher than that of pure TC. The closely spaced band structures and close contact surfaces between T C and NH<sub>2</sub>-MIL-125(Ti) should be the origin of the core–shell’s increased photocatalytic activity, as they facilitate the efficient transfer and separation of the photo-generated charge carriers. Cu<sup>2+</sup> proportion to Cu<sup>1+</sup> after core–shell preparation is 45.66 %, which causes more oxygen vacancy and charge imbalances, increasing reactant adsorption and light absorption in the visible spectrum. The stability test towards MB employing T C@NH<sub>2-</sub>MIL-125(Ti) core–shell and the photocatalytic scavenger test have also been studied. Moreover, a Type-II heterojunction was produced by photo-generated electron transfer from T C to NH<sub>2</sub>-MIL-125(Ti). Such a heterostructure sheds light on Cu<sub>2</sub>O-related core–shell materials’ exceptionally effective recombination suppression and improved photocatalytic effectiveness.</div></div>","PeriodicalId":272,"journal":{"name":"Chemical Physics","volume":"591 ","pages":"Article 112602"},"PeriodicalIF":2.0,"publicationDate":"2025-01-05","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143164937","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"化学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2025-01-04DOI: 10.1016/j.chemphys.2025.112603
Hajar Lamouadene , Majid EL Kassaoui , Mourad El Yadari , Abdallah El Kenz , Abdelilah Benyoussef
Machine learning, as one of the promising alternatives for solving complex challenges, has recently received considerable attention. In this study, we apply several well-established machine-learning models for predicting the energy band gap of doped-ZnO as well as novel doping concentrations. This approach significantly expands the possibilities for designing functional materials, offering innovative solutions to meet current energy needs. The results show that the Gaussian Process Regression (GPR) model achieved outstanding performance, with a correlation coefficient (CC) of 98.97%, a root mean square error (RMSE) of 0.0022, and a mean absolute error (MAE) of 0.0020. Comparatively, the Support Vector Machine (SVM) model recorded a CC of 83.70%, an RMSE of 0.0052, and an MAE of 0.0048, while the Random Forest model exhibited a CC of 76.40%, an RMSE of 0.0086, and an MAE of 0.0083. These results underscore the exceptional effectiveness of the GPR model in predicting material properties, while also highlighting the significant contributions of the SVM and Random Forest (RF) methods. This study opens up new research avenues in the fields of materials science and catalysis by exploring the predictive capabilities of different machine learning models for designing functional materials. We emphasize that the selection of the appropriate modeling method is critical for accurately predicting material properties. These results pave the way for future investigations aimed at refining and further comparing the performances of different modeling methods to optimize photocatalytic materials and address the challenges of clean energy.
{"title":"Exploring modeling techniques for predicting band gaps of Doped-ZnO: A Machine learning approach","authors":"Hajar Lamouadene , Majid EL Kassaoui , Mourad El Yadari , Abdallah El Kenz , Abdelilah Benyoussef","doi":"10.1016/j.chemphys.2025.112603","DOIUrl":"10.1016/j.chemphys.2025.112603","url":null,"abstract":"<div><div>Machine learning, as one of the promising alternatives for solving complex challenges, has recently received considerable attention. In this study, we apply several well-established machine-learning models for predicting the energy band gap of doped-ZnO as well as novel doping concentrations. This approach significantly expands the possibilities for designing functional materials, offering innovative solutions to meet current energy needs. The results show that the Gaussian Process Regression (GPR) model achieved outstanding performance, with a correlation coefficient (CC) of 98.97%, a root mean square error (RMSE) of 0.0022, and a mean absolute error (MAE) of 0.0020. Comparatively, the Support Vector Machine (SVM) model recorded a CC of 83.70%, an RMSE of 0.0052, and an MAE of 0.0048, while the Random Forest model exhibited a CC of 76.40%, an RMSE of 0.0086, and an MAE of 0.0083. These results underscore the exceptional effectiveness of the GPR model in predicting material properties, while also highlighting the significant contributions of the SVM and Random Forest (RF) methods. This study opens up new research avenues in the fields of materials science and catalysis by exploring the predictive capabilities of different machine learning models for designing functional materials. We emphasize that the selection of the appropriate modeling method is critical for accurately predicting material properties. These results pave the way for future investigations aimed at refining and further comparing the performances of different modeling methods to optimize photocatalytic materials and address the challenges of clean energy.</div></div>","PeriodicalId":272,"journal":{"name":"Chemical Physics","volume":"591 ","pages":"Article 112603"},"PeriodicalIF":2.0,"publicationDate":"2025-01-04","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143164859","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"化学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2025-01-03DOI: 10.1016/j.chemphys.2025.112600
Muhammad Hamid , Muhammad Faizan , Tahani A. Alrebdi , Kausar Shaheen , Shah Haidar Khan
Chalcogenide materials have garnered significant attention for their excellent performance in optoelectronic and thermoelectric applications. This study explores the band structure and thermoelectric properties of ternary chalcogenides LiSbX2 (X = S, Se. Te) using density functional theory (DFT). Our analysis reveals that these compounds exhibit negative formation energies and positive phonon frequencies, indicating their stability and a possible easy synthesis. The band structure calculations show that LiSbX2 (X = S, Se, Te) are indirect bandgap semiconductors with a band gap of 0.96 (LiSbS2), 0.52 (LiSbSe2), and 0.13 eV (LiSbTe2). Notably, these materials exhibit a high Seebeck coefficient, low electronic thermal conductivity, and high electronic conductivity. The maximum figure of merit is 0.61, 0.57, and 0.31 for LiSbS2, LiSbSe2, and LiSbTe2, respectively, at 1000 K. These findings highlight the suitability of these compounds for future thermoelectric applications.
{"title":"Computational study of the lattice type, band structure, and thermoelectric properties of LiSbX2 (X = S, Se, Te)","authors":"Muhammad Hamid , Muhammad Faizan , Tahani A. Alrebdi , Kausar Shaheen , Shah Haidar Khan","doi":"10.1016/j.chemphys.2025.112600","DOIUrl":"10.1016/j.chemphys.2025.112600","url":null,"abstract":"<div><div>Chalcogenide materials have garnered significant attention for their excellent performance in optoelectronic and thermoelectric applications. This study explores the band structure and thermoelectric properties of ternary chalcogenides LiSbX<sub>2</sub> (X = S, Se. Te) using density functional theory (DFT). Our analysis reveals that these compounds exhibit negative formation energies and positive phonon frequencies, indicating their stability and a possible easy synthesis. The band structure calculations show that LiSbX<sub>2</sub> (X = S, Se, Te) are indirect bandgap semiconductors with a band gap of 0.96 (LiSbS<sub>2</sub>), 0.52 (LiSbSe<sub>2</sub>), and 0.13 eV (LiSbTe<sub>2</sub>). Notably, these materials exhibit a high Seebeck coefficient, low electronic thermal conductivity, and high electronic conductivity. The maximum figure of merit is 0.61, 0.57, and 0.31 for LiSbS<sub>2</sub>, LiSbSe<sub>2</sub>, and LiSbTe<sub>2</sub>, respectively, at 1000 K. These findings highlight the suitability of these compounds for future thermoelectric applications.</div></div>","PeriodicalId":272,"journal":{"name":"Chemical Physics","volume":"591 ","pages":"Article 112600"},"PeriodicalIF":2.0,"publicationDate":"2025-01-03","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143164860","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"化学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2025-01-03DOI: 10.1016/j.chemphys.2024.112594
Khaled E. El-Kelany , Alexander Platonenko , Julio Sambrano , Klaus Doll , Roberto Dovesi
<div><div>The charge and spin density distributions of five LaBO<span><math><msub><mrow></mrow><mrow><mn>3</mn></mrow></msub></math></span> perovskites (B = Sc, Ti, V, Cr, and Co) have been investigated through the Mulliken population analysis, which yields crucial insights into the net atomic charges Q, magnetic moments <span><math><mi>μ</mi></math></span>, and bond populations BP. The occupancy of the d shell and of the individual d orbitals of the transition metals B are also discussed. Large differences are observed with respect to the fully ionic representation (or <em>oxidation state</em>), La<span><math><msup><mrow></mrow><mrow><mo>+</mo><mn>3</mn></mrow></msup></math></span>, B<span><math><msup><mrow></mrow><mrow><mo>+</mo><mn>3</mn></mrow></msup></math></span> and O<sup>−2</sup>, which implies that the B atom loses the two 4s electrons and one of the d electrons, so that Sc would be d<span><math><msup><mrow></mrow><mrow><mn>0</mn></mrow></msup></math></span>, Ti d<span><math><msup><mrow></mrow><mrow><mn>1</mn></mrow></msup></math></span>, V d<span><math><msup><mrow></mrow><mrow><mn>2</mn></mrow></msup></math></span> and so on. The results of the quantum mechanical calculations (with an <em>all electron</em> Gaussian type basis set, hybrid functionals and the CRYSTAL code) show that the d occupancy on B is very close to the one of the isolated neutral atom: Sc=0.91 vs 1.0, Ti=2.02 vs 2.0, V=2.91 vs 3.0, Cr=4.07 vs 4.0, Co 7.07 vs 7.0, in contrast with the fully ionic model. The net atomic charges, Q, on the atom B, are far from the ionic limit: +2.06, +1.92, +2.05, +1.81 and +1.74 from Sc to Co. The B net charges are then close to +2(instead of the formal ionic value of +3), with a maximum difference of −0.3 for Co. This lower atomic charge is compensated by the oxygen charge which is slightly oscillating between −1.48 and −1.62 (instead of −2), whereas the La net charge is around +2.70 (instead of the formal +3 value). The reduced ionicity involves then, rather than the d shell, the partial occupancy of the 4s orbitals and their interaction with the p orbitals of oxygen. At variance with respect to Q, the atomic magnetic moments <span><math><mi>μ</mi></math></span> are very close to the ideal values: 0.96 vs 1 <span><math><mrow><mo>|</mo><mi>e</mi><mo>|</mo></mrow></math></span> for Ti, 1.90 vs 2 <span><math><mrow><mo>|</mo><mi>e</mi><mo>|</mo></mrow></math></span> for V, 2.88 vs 3 <span><math><mrow><mo>|</mo><mi>e</mi><mo>|</mo></mrow></math></span> for Cr (the ground state of the Sc and Co compounds is closed shell, with no spin polarization). The Q and <span><math><mi>μ</mi></math></span> values of three fluorides (KScF<span><math><msub><mrow></mrow><mrow><mn>3</mn></mrow></msub></math></span>, KCrF<span><math><msub><mrow></mrow><mrow><mn>3</mn></mrow></msub></math></span>, KCoF<span><math><msub><mrow></mrow><mrow><mn>3</mn></mrow></msub></math></span>) are also presented, to evidentiate the large differences between oxides and fluori
{"title":"The charge and spin density of five LaBO3 perovskites (B=Sc, Ti, V, Cr and Co). A Mulliken analysis","authors":"Khaled E. El-Kelany , Alexander Platonenko , Julio Sambrano , Klaus Doll , Roberto Dovesi","doi":"10.1016/j.chemphys.2024.112594","DOIUrl":"10.1016/j.chemphys.2024.112594","url":null,"abstract":"<div><div>The charge and spin density distributions of five LaBO<span><math><msub><mrow></mrow><mrow><mn>3</mn></mrow></msub></math></span> perovskites (B = Sc, Ti, V, Cr, and Co) have been investigated through the Mulliken population analysis, which yields crucial insights into the net atomic charges Q, magnetic moments <span><math><mi>μ</mi></math></span>, and bond populations BP. The occupancy of the d shell and of the individual d orbitals of the transition metals B are also discussed. Large differences are observed with respect to the fully ionic representation (or <em>oxidation state</em>), La<span><math><msup><mrow></mrow><mrow><mo>+</mo><mn>3</mn></mrow></msup></math></span>, B<span><math><msup><mrow></mrow><mrow><mo>+</mo><mn>3</mn></mrow></msup></math></span> and O<sup>−2</sup>, which implies that the B atom loses the two 4s electrons and one of the d electrons, so that Sc would be d<span><math><msup><mrow></mrow><mrow><mn>0</mn></mrow></msup></math></span>, Ti d<span><math><msup><mrow></mrow><mrow><mn>1</mn></mrow></msup></math></span>, V d<span><math><msup><mrow></mrow><mrow><mn>2</mn></mrow></msup></math></span> and so on. The results of the quantum mechanical calculations (with an <em>all electron</em> Gaussian type basis set, hybrid functionals and the CRYSTAL code) show that the d occupancy on B is very close to the one of the isolated neutral atom: Sc=0.91 vs 1.0, Ti=2.02 vs 2.0, V=2.91 vs 3.0, Cr=4.07 vs 4.0, Co 7.07 vs 7.0, in contrast with the fully ionic model. The net atomic charges, Q, on the atom B, are far from the ionic limit: +2.06, +1.92, +2.05, +1.81 and +1.74 from Sc to Co. The B net charges are then close to +2(instead of the formal ionic value of +3), with a maximum difference of −0.3 for Co. This lower atomic charge is compensated by the oxygen charge which is slightly oscillating between −1.48 and −1.62 (instead of −2), whereas the La net charge is around +2.70 (instead of the formal +3 value). The reduced ionicity involves then, rather than the d shell, the partial occupancy of the 4s orbitals and their interaction with the p orbitals of oxygen. At variance with respect to Q, the atomic magnetic moments <span><math><mi>μ</mi></math></span> are very close to the ideal values: 0.96 vs 1 <span><math><mrow><mo>|</mo><mi>e</mi><mo>|</mo></mrow></math></span> for Ti, 1.90 vs 2 <span><math><mrow><mo>|</mo><mi>e</mi><mo>|</mo></mrow></math></span> for V, 2.88 vs 3 <span><math><mrow><mo>|</mo><mi>e</mi><mo>|</mo></mrow></math></span> for Cr (the ground state of the Sc and Co compounds is closed shell, with no spin polarization). The Q and <span><math><mi>μ</mi></math></span> values of three fluorides (KScF<span><math><msub><mrow></mrow><mrow><mn>3</mn></mrow></msub></math></span>, KCrF<span><math><msub><mrow></mrow><mrow><mn>3</mn></mrow></msub></math></span>, KCoF<span><math><msub><mrow></mrow><mrow><mn>3</mn></mrow></msub></math></span>) are also presented, to evidentiate the large differences between oxides and fluori","PeriodicalId":272,"journal":{"name":"Chemical Physics","volume":"591 ","pages":"Article 112594"},"PeriodicalIF":2.0,"publicationDate":"2025-01-03","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143164750","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"化学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
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