Pub Date : 2025-02-28DOI: 10.1021/acs.jpcc.4c07856
Xue Liang, Bo Feng, Jiawei Xu, Yang Lu, Lina Wu, Guangbo Che
Two-dimensional covalent organic frameworks (2D COFs) have emerged as promising nonmetal photocatalysts for overall water-splitting (OWS) due to their exceptional crystallinity, large surface area, and versatile chemical architectures. However, achieving visible light-driven photocatalytic OWS with 2D COFs remains challenging. This is partly due to the stringent requirements for band alignment in hydrogen evolution reactions (HER) and oxygen evolution reactions (OER) and limitations in catalytic active sites. This study presents a comparative analysis of isomeric structured 2D COFs, resulting in the design of 12 two-dimensional COF materials. From these, five materials with outstanding visible light-driven OWS performance were identified. Through HSE06 method calculations, these COFs were characterized as semiconductors with tunable band gaps (1.91–3.11 eV), effectively covering the visible light spectrum. Notably, the valence and conduction band positions of five COFs are well-aligned with the redox potentials of H+/H2 and O2/H2O, indicating their excellent potential for efficient OWS. Additionally, COFs with trans configurations demonstrate spatial separation of active sites for hydrogen and oxygen evolution reactions, in which the theoretical energy conversion efficiency of CTF-NS1 can reach 9.23%. This study focuses on the fine-tuning of isomeric configurations in COF photocatalysts, enhancing the theoretical understanding of the structure–property relationship in COF materials.
{"title":"Design of Isomeric 2D COFs for Visible Light-Driven Overall Water Splitting: Insights and Electronic Structure Modulation","authors":"Xue Liang, Bo Feng, Jiawei Xu, Yang Lu, Lina Wu, Guangbo Che","doi":"10.1021/acs.jpcc.4c07856","DOIUrl":"https://doi.org/10.1021/acs.jpcc.4c07856","url":null,"abstract":"Two-dimensional covalent organic frameworks (2D COFs) have emerged as promising nonmetal photocatalysts for overall water-splitting (OWS) due to their exceptional crystallinity, large surface area, and versatile chemical architectures. However, achieving visible light-driven photocatalytic OWS with 2D COFs remains challenging. This is partly due to the stringent requirements for band alignment in hydrogen evolution reactions (HER) and oxygen evolution reactions (OER) and limitations in catalytic active sites. This study presents a comparative analysis of isomeric structured 2D COFs, resulting in the design of 12 two-dimensional COF materials. From these, five materials with outstanding visible light-driven OWS performance were identified. Through HSE06 method calculations, these COFs were characterized as semiconductors with tunable band gaps (1.91–3.11 eV), effectively covering the visible light spectrum. Notably, the valence and conduction band positions of five COFs are well-aligned with the redox potentials of H<sup>+</sup>/H<sub>2</sub> and O<sub>2</sub>/H<sub>2</sub>O, indicating their excellent potential for efficient OWS. Additionally, COFs with trans configurations demonstrate spatial separation of active sites for hydrogen and oxygen evolution reactions, in which the theoretical energy conversion efficiency of CTF-NS1 can reach 9.23%. This study focuses on the fine-tuning of isomeric configurations in COF photocatalysts, enhancing the theoretical understanding of the structure–property relationship in COF materials.","PeriodicalId":61,"journal":{"name":"The Journal of Physical Chemistry C","volume":"13 1","pages":""},"PeriodicalIF":4.126,"publicationDate":"2025-02-28","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143518374","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 : 2025-02-28DOI: 10.1021/acs.jpcc.4c07876
Heng Zhang, Aderinsola Oduntan, Zengqing Zhuo, Steven S. C. Chuang, Jinghua Guo, Jin Zhong Zhang
In this study, we investigated the solid residual poly(vinyl alcohol) (PVA) and TiO2 after nonthermal air, CO2, and N2 plasma depolymerization in the absence and presence of TiO2. Scanning electron microscopy studies showed the absence of highly viscous tar and carbonaceous residues on the surfaces of PVA and TiO2. In the absence of TiO2, PVA particles exhibited micron-sized holes on their surfaces, whereas in the presence of TiO2, the surface roughness of PVA particles was observed at the submicron scale. These observations suggest that TiO2 facilitates the even distribution of nonthermal plasma at a submicron scale, leading to a more uniform depolymerization of PVA surfaces. Raman, Fourier transform infrared spectroscopy, and X-ray absorption spectroscopy showed that (i) the surface of residual PVA contains mainly ketone functional groups and less C–H bonds than the pristine PVA and (ii) further confirmed the absence of highly viscous tar and carbonaceous residues on both used TiO2 and residual PVA. The nuclear magnetic resonance and mass spectroscopy suggested that the PVA is growing back to poly polyvinyl acetate by the esterification reaction, and the ethers are produced by the acetal reaction between PVA and aldehyde. The transmission electron microscopy and X-ray diffraction analysis indicated no major crystal structural change of the TiO2 catalyst after the plasma reactions. This study demonstrates that nonthermal plasma-assisted depolymerization is a viable alternative to thermal depolymerization, offering the unique advantage of converting polymer wastes into gaseous small organic molecules without generating recalcitrant viscous tar and carbonaceous residues on the surfaces of the polymer and TiO2 catalysts.
{"title":"New Insights into Nonthermal Plasma-Assisted Poly(vinyl alcohol) Depolymerization Catalyzed by TiO2","authors":"Heng Zhang, Aderinsola Oduntan, Zengqing Zhuo, Steven S. C. Chuang, Jinghua Guo, Jin Zhong Zhang","doi":"10.1021/acs.jpcc.4c07876","DOIUrl":"https://doi.org/10.1021/acs.jpcc.4c07876","url":null,"abstract":"In this study, we investigated the solid residual poly(vinyl alcohol) (PVA) and TiO<sub>2</sub> after nonthermal air, CO<sub>2</sub>, and N<sub>2</sub> plasma depolymerization in the absence and presence of TiO<sub>2</sub>. Scanning electron microscopy studies showed the absence of highly viscous tar and carbonaceous residues on the surfaces of PVA and TiO<sub>2</sub>. In the absence of TiO<sub>2</sub>, PVA particles exhibited micron-sized holes on their surfaces, whereas in the presence of TiO<sub>2</sub>, the surface roughness of PVA particles was observed at the submicron scale. These observations suggest that TiO<sub>2</sub> facilitates the even distribution of nonthermal plasma at a submicron scale, leading to a more uniform depolymerization of PVA surfaces. Raman, Fourier transform infrared spectroscopy, and X-ray absorption spectroscopy showed that (i) the surface of residual PVA contains mainly ketone functional groups and less C–H bonds than the pristine PVA and (ii) further confirmed the absence of highly viscous tar and carbonaceous residues on both used TiO<sub>2</sub> and residual PVA. The nuclear magnetic resonance and mass spectroscopy suggested that the PVA is growing back to poly polyvinyl acetate by the esterification reaction, and the ethers are produced by the acetal reaction between PVA and aldehyde. The transmission electron microscopy and X-ray diffraction analysis indicated no major crystal structural change of the TiO<sub>2</sub> catalyst after the plasma reactions. This study demonstrates that nonthermal plasma-assisted depolymerization is a viable alternative to thermal depolymerization, offering the unique advantage of converting polymer wastes into gaseous small organic molecules without generating recalcitrant viscous tar and carbonaceous residues on the surfaces of the polymer and TiO<sub>2</sub> catalysts.","PeriodicalId":61,"journal":{"name":"The Journal of Physical Chemistry C","volume":"193 1","pages":""},"PeriodicalIF":4.126,"publicationDate":"2025-02-28","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143518375","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 : 2025-02-28DOI: 10.1021/acs.jpcc.5c00090
Samita Mishra, Ashwani Gurjar, Arijit Kumar De
In recent times, lead-free layered double perovskites have drawn considerable attention because of their nontoxic nature, structural stability in ambient conditions, and ability to alter optoelectronic properties by changing the stoichiometry of two metal ions. However, the existence of defect states still remains a major bottleneck for using this class of materials. In order to explore the potential applications of this intriguing family of materials as an active light-absorbing layer in solar cells, the nature of these defect states and their impact in trapping charge carriers must be understood in depth. In this work, we present a thorough investigation of the effects of capping ligands on surface passivation of microcrystals of Cs4CuSb2Cl12, a relatively new halide double-perovskite. We use different capping ligands with varying concentrations to explore such an effect. We further demonstrate how the surface trap states and their passivation influence ultrafast charge-carrier relaxation dynamics by using femtosecond transient absorption spectroscopy. While the nature of surface passivation is unlikely to affect the charge-carrier dynamics in microcrystals, owing to the remoteness of the surface from the core region where the majority of the charge carriers are photogenerated, our results show that even for microcrystals, the dynamics are significantly altered.
{"title":"Elucidating Effect of Surface-Passivation on Charge-Carrier Relaxation Dynamics in Cs4CuSb2Cl12 Microcrystals","authors":"Samita Mishra, Ashwani Gurjar, Arijit Kumar De","doi":"10.1021/acs.jpcc.5c00090","DOIUrl":"https://doi.org/10.1021/acs.jpcc.5c00090","url":null,"abstract":"In recent times, lead-free layered double perovskites have drawn considerable attention because of their nontoxic nature, structural stability in ambient conditions, and ability to alter optoelectronic properties by changing the stoichiometry of two metal ions. However, the existence of defect states still remains a major bottleneck for using this class of materials. In order to explore the potential applications of this intriguing family of materials as an active light-absorbing layer in solar cells, the nature of these defect states and their impact in trapping charge carriers must be understood in depth. In this work, we present a thorough investigation of the effects of capping ligands on surface passivation of microcrystals of Cs<sub>4</sub>CuSb<sub>2</sub>Cl<sub>12</sub>, a relatively new halide double-perovskite. We use different capping ligands with varying concentrations to explore such an effect. We further demonstrate how the surface trap states and their passivation influence ultrafast charge-carrier relaxation dynamics by using femtosecond transient absorption spectroscopy. While the nature of surface passivation is unlikely to affect the charge-carrier dynamics in microcrystals, owing to the remoteness of the surface from the core region where the majority of the charge carriers are photogenerated, our results show that even for microcrystals, the dynamics are significantly altered.","PeriodicalId":61,"journal":{"name":"The Journal of Physical Chemistry C","volume":"44 1","pages":""},"PeriodicalIF":4.126,"publicationDate":"2025-02-28","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143518378","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 : 2025-02-28DOI: 10.1021/acs.jpcc.4c08175
Nadeesha P. W. Rathuwadu, Daniel L. Parr IV, Johna Leddy
In thin layer sonoelectrochemistry (TLS), ultrasound induces constructive interference in a thin fluid layer to increase interfacial rates. In TLS experiments, slow interfacial rates are increased during and after sonication. No cavitation or heating is observed in the fluid. A previously developed model quantifies how solvent properties impact TLS rates. Voltammetry for Fe3+ and benzoquinone in tetrahydrofuran, dimethylformamide, water, ethanol, and 2-propanol is undertaken with and without sonication. Rate enhancements vary with solvent properties, as quantitatively predicted by the model. The data vet the TLS model for nonaqueous solvents.
{"title":"Thin Layer Sonoelectrochemistry: The Solvents","authors":"Nadeesha P. W. Rathuwadu, Daniel L. Parr IV, Johna Leddy","doi":"10.1021/acs.jpcc.4c08175","DOIUrl":"https://doi.org/10.1021/acs.jpcc.4c08175","url":null,"abstract":"In thin layer sonoelectrochemistry (TLS), ultrasound induces constructive interference in a thin fluid layer to increase interfacial rates. In TLS experiments, slow interfacial rates are increased during and after sonication. No cavitation or heating is observed in the fluid. A previously developed model quantifies how solvent properties impact TLS rates. Voltammetry for Fe<sup>3+</sup> and benzoquinone in tetrahydrofuran, dimethylformamide, water, ethanol, and 2-propanol is undertaken with and without sonication. Rate enhancements vary with solvent properties, as quantitatively predicted by the model. The data vet the TLS model for nonaqueous solvents.","PeriodicalId":61,"journal":{"name":"The Journal of Physical Chemistry C","volume":"32 1","pages":""},"PeriodicalIF":4.126,"publicationDate":"2025-02-28","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143518376","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 : 2025-02-27DOI: 10.1021/acs.jpcc.4c08595
Simão M. João, Ottavio Bassano, Johannes Lischner
Energetic or “hot” electrons and holes generated from the decay of localized surface plasmons in metallic nanoparticles have great potential for applications in photocatalysis, photovoltaics, and sensing. Here, we study the generation of hot carriers in brick-shaped gold nanoparticles using a recently developed modeling approach that combines a solution to Maxwell’s equation with large-scale tight-binding simulations to evaluate Fermi’s Golden Rule. We find that hot-carrier generation depends sensitively on the aspect ratio of the nanobricks with flatter bricks, producing a large number of energetic electrons irrespective of the light polarization. In contrast, the hot-carrier generation rates of elongated nanobricks exhibit a strong dependence on the light polarization. The insights resulting from our calculations can be harnessed to design nanobricks that produce hot carriers with properties tailored to specific device applications.
{"title":"Aspect Ratio Controls Hot-Carrier Generation in Gold Nanobricks","authors":"Simão M. João, Ottavio Bassano, Johannes Lischner","doi":"10.1021/acs.jpcc.4c08595","DOIUrl":"https://doi.org/10.1021/acs.jpcc.4c08595","url":null,"abstract":"Energetic or “hot” electrons and holes generated from the decay of localized surface plasmons in metallic nanoparticles have great potential for applications in photocatalysis, photovoltaics, and sensing. Here, we study the generation of hot carriers in brick-shaped gold nanoparticles using a recently developed modeling approach that combines a solution to Maxwell’s equation with large-scale tight-binding simulations to evaluate Fermi’s Golden Rule. We find that hot-carrier generation depends sensitively on the aspect ratio of the nanobricks with flatter bricks, producing a large number of energetic electrons irrespective of the light polarization. In contrast, the hot-carrier generation rates of elongated nanobricks exhibit a strong dependence on the light polarization. The insights resulting from our calculations can be harnessed to design nanobricks that produce hot carriers with properties tailored to specific device applications.","PeriodicalId":61,"journal":{"name":"The Journal of Physical Chemistry C","volume":"30 1","pages":""},"PeriodicalIF":4.126,"publicationDate":"2025-02-27","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143518226","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}
High-dielectric-constant materials facilitate carrier transport by reducing the scattering, trapping, and recombination of carriers through the shielding of charged defects and impurities, enabling their advantageous application in optoelectronics. Materials containing bismuth and antimony cations exhibit excellent dielectric properties due to their soft lattice and the presence of ns2 lone pair electrons. In this study, we have combined first-principles calculations and machine learning methods to unravel the relationship between dielectric constant and physical features in 523 bismuth/antimony-based materials from the Inorganic Crystal Structure Database. We trained two Gradient Boosting Decision Tree regression models to predict the ionic and electronic dielectric constants and analyzed the critical features influencing these constants. Furthermore, utilizing Sure Independence Screening and Sparsifying Operator combined with these critical features, we fitted three dielectric descriptors, comprising four physical features─Polar center (PC), Packing fraction of Bi-/Sb-based polyhedron (PFBi,Sb), Energy of Highest Occupied Molecular Orbital (EHOMO), and Fraction of p valence electron (VEpfrac). The descriptors indicate that the larger the PC and the smaller the PFBi,Sb, the higher the ionic dielectric constants. Conversely, the larger the EHOMO and the smaller the VEpfrac, the more conducive it is to high electronic dielectric constants. Finally, we trained a random forest model to identify materials with high dielectric constants (ε > 20). Using this model, we screened out 4933 experimentally unsynthesized, potentially high-dielectric-constant materials containing bismuth or antimony from Open Quantum Materials Database. Thirty-eight thermodynamically stable sulfur-containing compounds were selected for density functional perturbation theory calculations. The results show that 86.8% of these materials have a dielectric constant greater than 20. Finally, 12 materials were identified with potential optoelectronic applications. This study provides valuable insights and practical tools for the design and identification of materials with desirable dielectric properties for promising optoelectronic applications.
{"title":"Machine Learning-Assisted Dielectric Screening of Bismuth/Antimony-Based Compounds for Promising Optoelectronic Semiconductors","authors":"Guoliang Luo, Xiaoyu Yang, Yansong Zhou, Kun Zhou, Junjie Feng, Jiahao Xie, Xin He, Lijun Zhang","doi":"10.1021/acs.jpcc.4c08372","DOIUrl":"https://doi.org/10.1021/acs.jpcc.4c08372","url":null,"abstract":"High-dielectric-constant materials facilitate carrier transport by reducing the scattering, trapping, and recombination of carriers through the shielding of charged defects and impurities, enabling their advantageous application in optoelectronics. Materials containing bismuth and antimony cations exhibit excellent dielectric properties due to their soft lattice and the presence of n<i>s</i><sup>2</sup> lone pair electrons. In this study, we have combined first-principles calculations and machine learning methods to unravel the relationship between dielectric constant and physical features in 523 bismuth/antimony-based materials from the Inorganic Crystal Structure Database. We trained two Gradient Boosting Decision Tree regression models to predict the ionic and electronic dielectric constants and analyzed the critical features influencing these constants. Furthermore, utilizing Sure Independence Screening and Sparsifying Operator combined with these critical features, we fitted three dielectric descriptors, comprising four physical features─Polar center (PC), Packing fraction of Bi-/Sb-based polyhedron (PF<sub>Bi,Sb</sub>), Energy of Highest Occupied Molecular Orbital (E<sub>HOMO</sub>), and Fraction of p valence electron (VE<sub>p</sub><sup>frac</sup>). The descriptors indicate that the larger the PC and the smaller the PF<sub>Bi,Sb</sub>, the higher the ionic dielectric constants. Conversely, the larger the E<sub>HOMO</sub> and the smaller the VE<sub>p</sub><sup>frac</sup>, the more conducive it is to high electronic dielectric constants. Finally, we trained a random forest model to identify materials with high dielectric constants (ε > 20). Using this model, we screened out 4933 experimentally unsynthesized, potentially high-dielectric-constant materials containing bismuth or antimony from Open Quantum Materials Database. Thirty-eight thermodynamically stable sulfur-containing compounds were selected for density functional perturbation theory calculations. The results show that 86.8% of these materials have a dielectric constant greater than 20. Finally, 12 materials were identified with potential optoelectronic applications. This study provides valuable insights and practical tools for the design and identification of materials with desirable dielectric properties for promising optoelectronic applications.","PeriodicalId":61,"journal":{"name":"The Journal of Physical Chemistry C","volume":"37 1","pages":""},"PeriodicalIF":4.126,"publicationDate":"2025-02-27","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143518223","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 : 2025-02-27DOI: 10.1021/acs.jpcc.4c08490
Qian-Xia Chen, Jin-Zhu Zhao
Hybrid organic–inorganic perovskites (HOIPs) are attractive for the application of functional materials that provide multiple degrees of freedom for ferro orders. By employing first-principles calculations, we propose the coexistence of ferroelectric and antiferromagnetic orders in AMnX3-type hybrid organic–inorganic perovskites (HOIPs) (A = NH4+, CH3NH3+, and CH3CH2NH3+, X= Cl, Br, I), which are distinguished from conventional inorganic perovskites, where the magnetic and ferroelectric orders often suppress each other. On the one hand, we show that the antiferroelectric magnetic order originates from the Mn sublattice. On the other hand, the spontaneous ferroelectric order in AMnX3-type HOIPs may have different origins depending on the size of the A-site organic molecules and are strongly affected by their interaction with the inorganic lattice frame. This work provides a promising strategy for subsequent investigations and applications of multiferroic materials.
{"title":"Coexistence of Ferroelectricity and Antiferromagnetism in Manganese-Based Hybrid Organic–Inorganic Perovskites","authors":"Qian-Xia Chen, Jin-Zhu Zhao","doi":"10.1021/acs.jpcc.4c08490","DOIUrl":"https://doi.org/10.1021/acs.jpcc.4c08490","url":null,"abstract":"Hybrid organic–inorganic perovskites (HOIPs) are attractive for the application of functional materials that provide multiple degrees of freedom for ferro orders. By employing first-principles calculations, we propose the coexistence of ferroelectric and antiferromagnetic orders in AMnX<sub>3</sub>-type hybrid organic–inorganic perovskites (HOIPs) (A = NH<sub>4</sub><sup>+</sup>, CH<sub>3</sub>NH<sub>3</sub><sup>+</sup>, and CH<sub>3</sub>CH<sub>2</sub>NH<sub>3</sub><sup>+</sup>, X= Cl, Br, I), which are distinguished from conventional inorganic perovskites, where the magnetic and ferroelectric orders often suppress each other. On the one hand, we show that the antiferroelectric magnetic order originates from the Mn sublattice. On the other hand, the spontaneous ferroelectric order in AMnX<sub>3</sub>-type HOIPs may have different origins depending on the size of the A-site organic molecules and are strongly affected by their interaction with the inorganic lattice frame. This work provides a promising strategy for subsequent investigations and applications of multiferroic materials.","PeriodicalId":61,"journal":{"name":"The Journal of Physical Chemistry C","volume":"15 1","pages":""},"PeriodicalIF":4.126,"publicationDate":"2025-02-27","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143518224","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 : 2025-02-27DOI: 10.1021/acs.jpcc.4c08823
Chathura B. Wijethunga, Melissa E. King
Colloidally synthesized nanoparticles are typically composed of noble metals due to their ease of use, which limits the development of tailorable catalytic materials. Non-noble metals are employed effectively as catalysts at the industrial scale, and their inclusion in nanoscale catalyst development has the potential to expand relevant pairings significantly. The inclusion of non-noble, crustally abundant metals, however, presents unique challenges including self-oxidation and negative reduction potentials, which limits the utility of conventional synthetic methods. Fundamental insights are critical to the expansion of available metals used in the formation of nanoparticles to include non-noble metals. This work highlights two key protocols for the synthesis of monodisperse spherical nickel/nickel oxide nanoparticles of tailorable sizes and subsequent transformation via galvanic exchange with copper ions to produce cubic and cuboctahedral copper oxide nanoparticles as well as controllable methods for the formation of bimetallic nickel–copper nanostructures. This innovative approach takes place in nanopure water at room temperature with no surfactants as a result of the thermodynamically favorable conditions. Additionally, the formation of shaped nanoparticles from a spherical nanoparticle via galvanic exchange is significantly different from that of known syntheses. This work provides critical insights into the strategic coupling of non-noble metals and elucidates a method to leverage galvanic exchange reactions in non-noble metal systems.
{"title":"Leveraging Galvanic Exchange for the Formation of Shaped Metal Nanoparticles Comprising Non-Noble Metals","authors":"Chathura B. Wijethunga, Melissa E. King","doi":"10.1021/acs.jpcc.4c08823","DOIUrl":"https://doi.org/10.1021/acs.jpcc.4c08823","url":null,"abstract":"Colloidally synthesized nanoparticles are typically composed of noble metals due to their ease of use, which limits the development of tailorable catalytic materials. Non-noble metals are employed effectively as catalysts at the industrial scale, and their inclusion in nanoscale catalyst development has the potential to expand relevant pairings significantly. The inclusion of non-noble, crustally abundant metals, however, presents unique challenges including self-oxidation and negative reduction potentials, which limits the utility of conventional synthetic methods. Fundamental insights are critical to the expansion of available metals used in the formation of nanoparticles to include non-noble metals. This work highlights two key protocols for the synthesis of monodisperse spherical nickel/nickel oxide nanoparticles of tailorable sizes and subsequent transformation via galvanic exchange with copper ions to produce cubic and cuboctahedral copper oxide nanoparticles as well as controllable methods for the formation of bimetallic nickel–copper nanostructures. This innovative approach takes place in nanopure water at room temperature with no surfactants as a result of the thermodynamically favorable conditions. Additionally, the formation of shaped nanoparticles from a spherical nanoparticle via galvanic exchange is significantly different from that of known syntheses. This work provides critical insights into the strategic coupling of non-noble metals and elucidates a method to leverage galvanic exchange reactions in non-noble metal systems.","PeriodicalId":61,"journal":{"name":"The Journal of Physical Chemistry C","volume":"3 1","pages":""},"PeriodicalIF":4.126,"publicationDate":"2025-02-27","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143518228","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 : 2025-02-27DOI: 10.1021/acs.jpcc.4c08613
Alessia Colosimo, Aurélien Crut, Noëlle Lascoux, Clément Panais, Alessandro Casto, Fabien Vialla, Valeria Demontis, Leonardo Martini, Paolo Rosi, Enzo Rotunno, Gian Carlo Gazzadi, Marco Beleggia, Manjunath Krishnappa, Alla Zak, Fabio Beltram, Francesco Rossella, Fabrice Vallée, Natalia Del Fatti, Francesco Banfi, Paolo Maioli
The experimentally retrieved value of the optical extinction cross section per unit length, σL,extNT, of individual MoS2 multiwall nanotubes (NTs) is here reported over the 440–940 nm wavelength range for light polarization both parallel and perpendicular to the nanotube longitudinal axis. The impact of nanotube diameter and environment on σL,extNT is addressed for individual nanotubes with diameters of 120 and 220 nm in suspended, sapphire-supported, and PMMA-supported configurations. Measuring individual nanotubes is of utmost importance given the wide nanotube size dispersion intrinsic to the synthesis process. The findings are interpreted in conjunction with finite element method simulations, informed by morphological input parameters from electron microscopy, offering insight into the respective contributions of absorption and scattering cross sections per unit length to overall σL,extNT. These quantitative results are of relevance in view of optoelectronics applications involving MoS2 nanotubes while providing benchmark values for theoretical investigations on their nano-optical response.
{"title":"Single MoS2 Nanotube Experimental Optical Extinction Cross Section","authors":"Alessia Colosimo, Aurélien Crut, Noëlle Lascoux, Clément Panais, Alessandro Casto, Fabien Vialla, Valeria Demontis, Leonardo Martini, Paolo Rosi, Enzo Rotunno, Gian Carlo Gazzadi, Marco Beleggia, Manjunath Krishnappa, Alla Zak, Fabio Beltram, Francesco Rossella, Fabrice Vallée, Natalia Del Fatti, Francesco Banfi, Paolo Maioli","doi":"10.1021/acs.jpcc.4c08613","DOIUrl":"https://doi.org/10.1021/acs.jpcc.4c08613","url":null,"abstract":"The experimentally retrieved value of the optical extinction cross section per unit length, σ<sub>L,ext</sub><sup>NT</sup>, of individual MoS<sub>2</sub> multiwall nanotubes (NTs) is here reported over the 440–940 nm wavelength range for light polarization both parallel and perpendicular to the nanotube longitudinal axis. The impact of nanotube diameter and environment on σ<sub>L,ext</sub><sup>NT</sup> is addressed for individual nanotubes with diameters of 120 and 220 nm in suspended, sapphire-supported, and PMMA-supported configurations. Measuring individual nanotubes is of utmost importance given the wide nanotube size dispersion intrinsic to the synthesis process. The findings are interpreted in conjunction with finite element method simulations, informed by morphological input parameters from electron microscopy, offering insight into the respective contributions of absorption and scattering cross sections per unit length to overall σ<sub>L,ext</sub><sup>NT</sup>. These quantitative results are of relevance in view of optoelectronics applications involving MoS<sub>2</sub> nanotubes while providing benchmark values for theoretical investigations on their nano-optical response.","PeriodicalId":61,"journal":{"name":"The Journal of Physical Chemistry C","volume":"16 1","pages":""},"PeriodicalIF":4.126,"publicationDate":"2025-02-27","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143518225","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}
The conversion of biomass into biofuels is imperative for sustainable energy production. Aldol condensation, which facilitates the formation of new C–C bonds from small molecules to larger compounds, represents an efficient strategy for harnessing biomass-derived products. In this study, we conducted a combined investigation employing density functional theory (DFT) calculations to elucidate the key factors enhancing the activity of aldol condensation over various metal oxide catalysts (ZnO, TiO2, CeO2, and ZrO2). Our results demonstrate a strong correlation between the ability of lattice oxygen to accept hydrogen and the aldol condensation activity in the absence of water. Furthermore, we investigated the impact of water on the aldol condensation reaction and discovered that the ability to dissociate water molecules is closely linked to their activity in aldol condensation reactions in the presence of water. Interestingly, catalysts with lower water dissociation ability exhibit enhanced aldol condensation activity in the presence of water. However, an excessively low water dissociation ability can impede the formation of active surface hydroxyl species, transforming water dissociation into a rate-determining step rather than promoting aldol condensation. Our study presents the significance of comprehending the role of water in aldol condensation reactions and provides valuable insights into optimizing catalyst design for efficient biofuel production from biomass-derived feedstocks.
{"title":"Unraveling the Influence of Water on the Catalytic Activity of Furfural-Acetone Aldol Condensation Over Metal Oxide Catalysts","authors":"Jinwoo Hwang, Il-Ho Choi, Kiheon Sung, Hyeonae Im, Kyung-Ran Hwang, Jeong Woo Han","doi":"10.1021/acs.jpcc.4c08199","DOIUrl":"https://doi.org/10.1021/acs.jpcc.4c08199","url":null,"abstract":"The conversion of biomass into biofuels is imperative for sustainable energy production. Aldol condensation, which facilitates the formation of new C–C bonds from small molecules to larger compounds, represents an efficient strategy for harnessing biomass-derived products. In this study, we conducted a combined investigation employing density functional theory (DFT) calculations to elucidate the key factors enhancing the activity of aldol condensation over various metal oxide catalysts (ZnO, TiO<sub>2</sub>, CeO<sub>2</sub>, and ZrO<sub>2</sub>). Our results demonstrate a strong correlation between the ability of lattice oxygen to accept hydrogen and the aldol condensation activity in the absence of water. Furthermore, we investigated the impact of water on the aldol condensation reaction and discovered that the ability to dissociate water molecules is closely linked to their activity in aldol condensation reactions in the presence of water. Interestingly, catalysts with lower water dissociation ability exhibit enhanced aldol condensation activity in the presence of water. However, an excessively low water dissociation ability can impede the formation of active surface hydroxyl species, transforming water dissociation into a rate-determining step rather than promoting aldol condensation. Our study presents the significance of comprehending the role of water in aldol condensation reactions and provides valuable insights into optimizing catalyst design for efficient biofuel production from biomass-derived feedstocks.","PeriodicalId":61,"journal":{"name":"The Journal of Physical Chemistry C","volume":"27 1","pages":""},"PeriodicalIF":4.126,"publicationDate":"2025-02-27","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143518380","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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