It is known that atomic layer deposition (ALD) of Al2O3 using trimethylaluminum (TMA) on transition metal surfaces is dependent to the type of the metal element, so that only coinage metal surfaces show delayed nucleation. In this study, the molecular and dissociative adsorption of TMA on 20 transition metal surfaces were investigated using density functional theory (DFT) calculations. The adsorption energy of molecular TMA depends on the group numbers of the elements, so that late transition metals are expected to show weaker adsorption of TMA molecule compared to those on early transition metals. Dissociative adsorption of TMA is expected to spontaneously proceed on most transition metal surfaces. However, TMA is expected to have reversible molecular adsorption on the surfaces of Cu, Zn, Ag, and Cd. Together with low propensity toward oxidation, the nucleation delay of Al2O3 ALD on Cu and Ag can be explained.
{"title":"Adsorption of trimethylaluminum on period 4 and 5 transition metal surfaces","authors":"Hyobin Eom, Sungmin Lee, Yohan Choi, Bonggeun Shong","doi":"10.1016/j.susc.2025.122711","DOIUrl":"10.1016/j.susc.2025.122711","url":null,"abstract":"<div><div>It is known that atomic layer deposition (ALD) of Al<sub>2</sub>O<sub>3</sub> using trimethylaluminum (TMA) on transition metal surfaces is dependent to the type of the metal element, so that only coinage metal surfaces show delayed nucleation. In this study, the molecular and dissociative adsorption of TMA on 20 transition metal surfaces were investigated using density functional theory (DFT) calculations. The adsorption energy of molecular TMA depends on the group numbers of the elements, so that late transition metals are expected to show weaker adsorption of TMA molecule compared to those on early transition metals. Dissociative adsorption of TMA is expected to spontaneously proceed on most transition metal surfaces. However, TMA is expected to have reversible molecular adsorption on the surfaces of Cu, Zn, Ag, and Cd. Together with low propensity toward oxidation, the nucleation delay of Al<sub>2</sub>O<sub>3</sub> ALD on Cu and Ag can be explained.</div></div>","PeriodicalId":22100,"journal":{"name":"Surface Science","volume":"755 ","pages":"Article 122711"},"PeriodicalIF":2.1,"publicationDate":"2025-02-07","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143372198","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"化学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2025-01-31DOI: 10.1016/j.susc.2025.122710
Anran Zhong , Yuhao Qiu , Huimin Hu , Jin-Ho Choi
Expanding the interlayer spacing of graphene layers has emerged as an effective strategy to enhance sodiation behavior in sodium-ion batteries. However, the optimal interlayer spacing that facilitates sodiation and maximizes electrochemical storage performance remain incompletely understood. In this study, we utilized first-principles density functional theory calculations to explore possible doping strategies aimed at modulating the interlayer spacing of bilayer graphene (BLG) to optimize its sodiation behavior. We investigated single-atom- and co-doping of BLG with various non-metal, transition metal, and metal elements. Most dopants resulted in significantly increased interlayer spacings of BLG, potentially enhancing sodiation capacity. Notably, among the systems considered, Zn–Ge co-doped BLG exhibited the highest theoretical capacity of 828 mAhg–1, surpassing the value of pristine BLG (124 mAhg–1). Moreover, Zn–Ge doped BLG showed a relatively low energy barrier (0.25 eV) against Na diffusion, which is desirable for facilitating rapid charge and discharge processes. These findings have implications for the design of high-performance graphene-based anode materials for sodium-ion batteries.
{"title":"Doped bilayer graphene for enhanced sodium-ion battery performance: a first-principles investigation","authors":"Anran Zhong , Yuhao Qiu , Huimin Hu , Jin-Ho Choi","doi":"10.1016/j.susc.2025.122710","DOIUrl":"10.1016/j.susc.2025.122710","url":null,"abstract":"<div><div>Expanding the interlayer spacing of graphene layers has emerged as an effective strategy to enhance sodiation behavior in sodium-ion batteries. However, the optimal interlayer spacing that facilitates sodiation and maximizes electrochemical storage performance remain incompletely understood. In this study, we utilized first-principles density functional theory calculations to explore possible doping strategies aimed at modulating the interlayer spacing of bilayer graphene (BLG) to optimize its sodiation behavior. We investigated single-atom- and co-doping of BLG with various non-metal, transition metal, and metal elements. Most dopants resulted in significantly increased interlayer spacings of BLG, potentially enhancing sodiation capacity. Notably, among the systems considered, Zn–Ge co-doped BLG exhibited the highest theoretical capacity of 828 mAhg<sup>–1</sup>, surpassing the value of pristine BLG (124 mAhg<sup>–1</sup>). Moreover, Zn–Ge doped BLG showed a relatively low energy barrier (0.25 eV) against Na diffusion, which is desirable for facilitating rapid charge and discharge processes. These findings have implications for the design of high-performance graphene-based anode materials for sodium-ion batteries.</div></div>","PeriodicalId":22100,"journal":{"name":"Surface Science","volume":"755 ","pages":"Article 122710"},"PeriodicalIF":2.1,"publicationDate":"2025-01-31","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143128934","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"化学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2025-01-29DOI: 10.1016/j.susc.2025.122703
Nguyen Hoang Linh , Pham Quoc Viet , Tran The Quang , Dinh The Hung , Do Van Truong
Our study systematically investigates the mechanical, optoelectronics, and piezoelectric properties of the buckled honeycomb GeSe monolayer (BH-GeSe) using first-principles theory. The stability of the BH-GeSe monolayer is confirmed through phonon dispersion, thermal stability, binding energy, and elastic constant analyses. Its small Young's modulus of 31.05 N/m imparts exceptional flexibility, with an ideal stress (σbia) of 6.2 N/m and a high fracture strain (εbia) of 0.2. The optoelectronic properties are analyzed through energy band structures and light absorption spectra. The BH-GeSe monolayer is identified as an indirect semiconductor with a energy band gap of 2.95 eV at equilibrium. Biaxial strain induces notable changes in the conduction band minimum (CBM), valence band maximum (VBM), and an energy band gap. Specifically, the energy band gap decreases by up to 51 % under strain. Light absorption coefficients and energy-loss spectra are significantly enhanced, particularly in the infrared and ultraviolet regions, showcasing its superior optical properties. Piezoelectric coefficients are derived from polarization variations in clamped-ion and relaxed-ion states. The piezoelectric coefficients d11 and d31 are calculated as 11.85 pm/V and −0.71 pm/V, respectively, indicating a robust piezoelectric response that surpasses many well-studied two-dimensional materials. These results highlight the BH-GeSe monolayer as a promising material for next-generation optoelectronic and piezoelectric devices. Outstanding flexibility, strain-tunable electronic properties, and strong piezoelectric response position the BH-GeSe monolayer as a leading candidate for diverse applications in advanced material science.
{"title":"First-principles analysis of mechanical, optoelectronics and piezoelectric properties in buckled honeycomb GeSe monolayer","authors":"Nguyen Hoang Linh , Pham Quoc Viet , Tran The Quang , Dinh The Hung , Do Van Truong","doi":"10.1016/j.susc.2025.122703","DOIUrl":"10.1016/j.susc.2025.122703","url":null,"abstract":"<div><div>Our study systematically investigates the mechanical, optoelectronics, and piezoelectric properties of the buckled honeycomb GeSe monolayer (BH-GeSe) using first-principles theory. The stability of the BH-GeSe monolayer is confirmed through phonon dispersion, thermal stability, binding energy, and elastic constant analyses. Its small Young's modulus of 31.05 N/m imparts exceptional flexibility, with an ideal stress (σ<em><sub>bia</sub></em>) of 6.2 N/m and a high fracture strain (ε<em><sub>bia</sub></em>) of 0.2. The optoelectronic properties are analyzed through energy band structures and light absorption spectra. The BH-GeSe monolayer is identified as an indirect semiconductor with a energy band gap of 2.95 eV at equilibrium. Biaxial strain induces notable changes in the conduction band minimum (CBM), valence band maximum (VBM), and an energy band gap. Specifically, the energy band gap decreases by up to 51 % under strain. Light absorption coefficients and energy-loss spectra are significantly enhanced, particularly in the infrared and ultraviolet regions, showcasing its superior optical properties. Piezoelectric coefficients are derived from polarization variations in clamped-ion and relaxed-ion states. The piezoelectric coefficients <em>d</em><sub>11</sub> and <em>d</em><sub>31</sub> are calculated as 11.85 pm/V and −0.71 pm/V, respectively, indicating a robust piezoelectric response that surpasses many well-studied two-dimensional materials. These results highlight the BH-GeSe monolayer as a promising material for next-generation optoelectronic and piezoelectric devices. Outstanding flexibility, strain-tunable electronic properties, and strong piezoelectric response position the BH-GeSe monolayer as a leading candidate for diverse applications in advanced material science.</div></div>","PeriodicalId":22100,"journal":{"name":"Surface Science","volume":"755 ","pages":"Article 122703"},"PeriodicalIF":2.1,"publicationDate":"2025-01-29","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143222238","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"化学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2025-01-28DOI: 10.1016/j.susc.2025.122701
Sajjan Mohammad , Neeta Bisht , Anjana Kannan , Anne Brandmeier , Christian Neiss , Andreas Görling , Meike Stöhr , Sabine Maier
The self-assembly of pyridyl-functionalized triazine (T4PT) was studied on Au(111) using low-temperature scanning tunneling microscopy (STM) under ultra-high vacuum conditions combined with density functional theory (DFT) calculations. In particular, we investigated the effect of temperature on the intermolecular interactions within the assemblies. STM measurements revealed that T4PT molecules formed a well-ordered, close-packed structure, with the molecules adopting a planar conformation parallel to the Au surface for coverages monolayer upon room temperature deposition. The intermolecular interactions stabilizing the self-assembled arrangement are based on a combination of hydrogen bonding and weak van der Waals forces. Upon post-deposition annealing up to C, the assemblies were additionally stabilized by metal–ligand bonding between the pyridyl ligands and native Au adatoms. Further post-deposition annealing at temperatures above C led to the breaking of the N-Au bonds with the molecular assemblies transforming into a second close-packed hydrogen-bonded structure. For temperatures exceeding C, few covalently linked dimers formed, most likely as a result of CH-bond activation. We rationalize the kinetically-driven structure formation by unveiling the interaction strengths of the different bonding motifs using DFT and compare the respective molecular conformations to the ones of the structurally similar pyridyl-functionalized benzene (T4PB).
{"title":"Pyridyl-functionalized tripod molecules on Au(111): Interplay between H-bonding and metal coordination","authors":"Sajjan Mohammad , Neeta Bisht , Anjana Kannan , Anne Brandmeier , Christian Neiss , Andreas Görling , Meike Stöhr , Sabine Maier","doi":"10.1016/j.susc.2025.122701","DOIUrl":"10.1016/j.susc.2025.122701","url":null,"abstract":"<div><div>The self-assembly of pyridyl-functionalized triazine (T4PT) was studied on Au(111) using low-temperature scanning tunneling microscopy (STM) under ultra-high vacuum conditions combined with density functional theory (DFT) calculations. In particular, we investigated the effect of temperature on the intermolecular interactions within the assemblies. STM measurements revealed that T4PT molecules formed a well-ordered, close-packed structure, with the molecules adopting a planar conformation parallel to the Au surface for coverages <span><math><mrow><mo>≤</mo><mn>1</mn></mrow></math></span> monolayer upon room temperature deposition. The intermolecular interactions stabilizing the self-assembled arrangement are based on a combination of hydrogen bonding and weak van der Waals forces. Upon post-deposition annealing up to <span><math><mrow><mn>200</mn><msup><mrow><mspace></mspace></mrow><mrow><mo>∘</mo></mrow></msup></mrow></math></span>C, the assemblies were additionally stabilized by metal–ligand bonding between the pyridyl ligands and native Au adatoms. Further post-deposition annealing at temperatures above <span><math><mrow><mn>200</mn><msup><mrow><mspace></mspace></mrow><mrow><mo>∘</mo></mrow></msup></mrow></math></span>C led to the breaking of the N-Au bonds with the molecular assemblies transforming into a second close-packed hydrogen-bonded structure. For temperatures exceeding <span><math><mrow><mn>230</mn><msup><mrow><mspace></mspace></mrow><mrow><mo>∘</mo></mrow></msup></mrow></math></span>C, few covalently linked dimers formed, most likely as a result of CH-bond activation. We rationalize the kinetically-driven structure formation by unveiling the interaction strengths of the different bonding motifs using DFT and compare the respective molecular conformations to the ones of the structurally similar pyridyl-functionalized benzene (T4PB).</div></div>","PeriodicalId":22100,"journal":{"name":"Surface Science","volume":"755 ","pages":"Article 122701"},"PeriodicalIF":2.1,"publicationDate":"2025-01-28","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143377401","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"化学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2025-01-25DOI: 10.1016/j.susc.2025.122700
C. Fwalo , A. Kochaev , R.E. Mapasha
<div><div>An increasing emphasis on 2D materials such as <span><math><msub><mrow><mi>β</mi></mrow><mrow><mn>12</mn></mrow></msub></math></span>-borophene has emerged in the pursuit of enhancing lithium and sodium-ion batteries, owing to their exceptional structural and electronic properties including low diffusion energy barriers. Although most of the results on diffusion mechanisms have been reported, they are largely limited to infinitely dilute concentrations. In this study, we used density functional theory to investigate the electronic properties of <span><math><msub><mrow><mi>β</mi></mrow><mrow><mn>12</mn></mrow></msub></math></span>-borophene adsorbed with high concentration of ions and determined its use as an electrode in lithium and sodium-ion batteries. Our systematic exploration involved the investigation of adsorption energies and diffusion mechanisms for single ions, vacancy, and knock-off at multiple ion levels. The findings indicate that <span><math><msub><mrow><mi>β</mi></mrow><mrow><mn>12</mn></mrow></msub></math></span>-borophene exhibits spontaneous adsorption energies towards Li and Na ions of -2.56 and -2.70 eV, respectively. Additionally, low open circuit voltages of 0.21 V for Li and 0.91 V for Na were obtained, suggesting that the formation of dendrites can be suppressed. At a high concentration of 24 ions, the storage capacity was calculated to be 1487.68 mAh/g for both Li and Na, surpassing that of commercial graphite electrodes and other 2D materials. We also observed charge transfer from the adsorbates to the substrate, with charge distributions primarily located between the first layers of ions and the substrate, indicating a significant concentration of electrons being transferred towards the substrate. We also investigated the energy barriers associated with diffusing vacancies (Li = 0.55 eV, Na = 0.22 eV) and knock-off mechanisms (Li = 0.56 eV, Na = 0.7 eV) at a high concentration of adsorbed ions and on a supercell that was twice the size of some previous studies. These results revealed varying energy barriers due to the presence of multiple ions, with the knock-off mechanism exhibiting the highest energy barrier. The increased energy barriers due to high concentration of ions is attributed to the repulsive forces between the ions. Furthermore, despite the adsorption of multiple Li and Na ions, <span><math><msub><mrow><mi>β</mi></mrow><mrow><mn>12</mn></mrow></msub></math></span>-borophene maintained its metallic properties, signifying its potential for use in battery operation cycles. Lastly, high structural stability at 300 K confirmed the viability of <span><math><msub><mrow><mi>β</mi></mrow><mrow><mn>12</mn></mrow></msub></math></span>-borophene for normal battery operations. Altogether, these properties underscore the potential of <span><math><msub><mrow><mi>β</mi></mrow><mrow><mn>12</mn></mrow></msub></math></span>-borophene as an effective electrode material for lithium and sodium-ion batteries.</div></div
{"title":"Understanding diffusion behavior of multiple Li and Na-ions on a β12-borophene electrode: A first-principles study","authors":"C. Fwalo , A. Kochaev , R.E. Mapasha","doi":"10.1016/j.susc.2025.122700","DOIUrl":"10.1016/j.susc.2025.122700","url":null,"abstract":"<div><div>An increasing emphasis on 2D materials such as <span><math><msub><mrow><mi>β</mi></mrow><mrow><mn>12</mn></mrow></msub></math></span>-borophene has emerged in the pursuit of enhancing lithium and sodium-ion batteries, owing to their exceptional structural and electronic properties including low diffusion energy barriers. Although most of the results on diffusion mechanisms have been reported, they are largely limited to infinitely dilute concentrations. In this study, we used density functional theory to investigate the electronic properties of <span><math><msub><mrow><mi>β</mi></mrow><mrow><mn>12</mn></mrow></msub></math></span>-borophene adsorbed with high concentration of ions and determined its use as an electrode in lithium and sodium-ion batteries. Our systematic exploration involved the investigation of adsorption energies and diffusion mechanisms for single ions, vacancy, and knock-off at multiple ion levels. The findings indicate that <span><math><msub><mrow><mi>β</mi></mrow><mrow><mn>12</mn></mrow></msub></math></span>-borophene exhibits spontaneous adsorption energies towards Li and Na ions of -2.56 and -2.70 eV, respectively. Additionally, low open circuit voltages of 0.21 V for Li and 0.91 V for Na were obtained, suggesting that the formation of dendrites can be suppressed. At a high concentration of 24 ions, the storage capacity was calculated to be 1487.68 mAh/g for both Li and Na, surpassing that of commercial graphite electrodes and other 2D materials. We also observed charge transfer from the adsorbates to the substrate, with charge distributions primarily located between the first layers of ions and the substrate, indicating a significant concentration of electrons being transferred towards the substrate. We also investigated the energy barriers associated with diffusing vacancies (Li = 0.55 eV, Na = 0.22 eV) and knock-off mechanisms (Li = 0.56 eV, Na = 0.7 eV) at a high concentration of adsorbed ions and on a supercell that was twice the size of some previous studies. These results revealed varying energy barriers due to the presence of multiple ions, with the knock-off mechanism exhibiting the highest energy barrier. The increased energy barriers due to high concentration of ions is attributed to the repulsive forces between the ions. Furthermore, despite the adsorption of multiple Li and Na ions, <span><math><msub><mrow><mi>β</mi></mrow><mrow><mn>12</mn></mrow></msub></math></span>-borophene maintained its metallic properties, signifying its potential for use in battery operation cycles. Lastly, high structural stability at 300 K confirmed the viability of <span><math><msub><mrow><mi>β</mi></mrow><mrow><mn>12</mn></mrow></msub></math></span>-borophene for normal battery operations. Altogether, these properties underscore the potential of <span><math><msub><mrow><mi>β</mi></mrow><mrow><mn>12</mn></mrow></msub></math></span>-borophene as an effective electrode material for lithium and sodium-ion batteries.</div></div","PeriodicalId":22100,"journal":{"name":"Surface Science","volume":"755 ","pages":"Article 122700"},"PeriodicalIF":2.1,"publicationDate":"2025-01-25","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143093380","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"化学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2025-01-23DOI: 10.1016/j.susc.2025.122702
Ming Meng , JiaLi Zhang , Yi Song , Jian Li , Yanling Hao , Yun Shan
Effective conversion from nitrate to ammonia using an electrochemical method is attracting much attention, but which has to face the difficulty of lower conversion performance and unavoidable competing reaction. Herein, we develop an intriguing surface engineering strategy to reorganize orderly the electronic structures of catalysts, in which the superficial Cu sites can be asymmetrically hybridized with internal Fe atoms through an indirect orbital interaction, finally leading to a semi-metallic characteristic to optimize the adsorption or dissociation process of nitrates. The comprehensive calculations confirm that the potential barriers at the rate-limiting steps can be effectively decreased due to their appropriate bonding interaction with reactants. More importantly, the competing hydrogen evolution reaction is also suppressed. This work suggests a feasible strategy to accelerate nitrate reduction by particular catalyst surface engineering.
{"title":"Semi-metallic reconfiguration induced by asymmetrically interatomic-interactions accelerate electrochemical nitrate reduction","authors":"Ming Meng , JiaLi Zhang , Yi Song , Jian Li , Yanling Hao , Yun Shan","doi":"10.1016/j.susc.2025.122702","DOIUrl":"10.1016/j.susc.2025.122702","url":null,"abstract":"<div><div>Effective conversion from nitrate to ammonia using an electrochemical method is attracting much attention, but which has to face the difficulty of lower conversion performance and unavoidable competing reaction. Herein, we develop an intriguing surface engineering strategy to reorganize orderly the electronic structures of catalysts, in which the superficial Cu sites can be asymmetrically hybridized with internal Fe atoms through an indirect orbital interaction, finally leading to a semi-metallic characteristic to optimize the adsorption or dissociation process of nitrates. The comprehensive calculations confirm that the potential barriers at the rate-limiting steps can be effectively decreased due to their appropriate bonding interaction with reactants. More importantly, the competing hydrogen evolution reaction is also suppressed. This work suggests a feasible strategy to accelerate nitrate reduction by particular catalyst surface engineering.</div></div>","PeriodicalId":22100,"journal":{"name":"Surface Science","volume":"755 ","pages":"Article 122702"},"PeriodicalIF":2.1,"publicationDate":"2025-01-23","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143128933","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"化学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2025-01-18DOI: 10.1016/j.susc.2025.122699
Joseph C. Loiselet, Mollie M. Corbett, James T. Whitted, Erin D. Schell, Ashleigh E. Baber
Exploring the formation of valuable chemical feedstocks from renewable sources is critical for decreasing global dependence on fossil fuels. The decomposition of ethanol forms acetaldehyde, a solvent and precursor for dyes, pesticides, pharmaceuticals and more; ethylene, which is crucial for the plastics industry; and clean hydrogen, a necessity for all hydrogenation reactions. While it is well known that Cu(111) and oxidized Cu(111) catalyze the dehydrogenation of small primary alcohols to form aldehydes, dehydration products to form alkenes are less discussed. An in depth study of the reactivity of ethanol on O/Cu(111) shows dehydrogenation, dehydration, and combustion products using temperature programmed reaction spectroscopy (TPRS). The presence of oxygen on O/Cu(111) resulted predominantly in acetaldehyde formation via the dehydrogenation pathway, with lesser amounts of ethylene via dehydration, as well as combustion products. Successive TPRS experiments resulted in decreased yields of all products due to the consumption of surface oxygen via water formation <200 K. Isotopic studies of ethanol–OD indicate the role of the hydroxyl hydrogen in water formation from Oads compared to water that desorbs during dehydration, as well as hydrogen formation via the dehydrogenation pathway. The dehydration pathway is proposed to occur via autocatalytic production of Oads during the ethoxy transformation to ethylene, furthering the reaction to form ethylene and CO2.
{"title":"Ethanol dehydrogenation and autocatalytic dehydration on oxidized Cu(111)","authors":"Joseph C. Loiselet, Mollie M. Corbett, James T. Whitted, Erin D. Schell, Ashleigh E. Baber","doi":"10.1016/j.susc.2025.122699","DOIUrl":"10.1016/j.susc.2025.122699","url":null,"abstract":"<div><div>Exploring the formation of valuable chemical feedstocks from renewable sources is critical for decreasing global dependence on fossil fuels. The decomposition of ethanol forms acetaldehyde, a solvent and precursor for dyes, pesticides, pharmaceuticals and more; ethylene, which is crucial for the plastics industry; and clean hydrogen, a necessity for all hydrogenation reactions. While it is well known that Cu(111) and oxidized Cu(111) catalyze the dehydrogenation of small primary alcohols to form aldehydes, dehydration products to form alkenes are less discussed. An in depth study of the reactivity of ethanol on O/Cu(111) shows dehydrogenation, dehydration, and combustion products using temperature programmed reaction spectroscopy (TPRS). The presence of oxygen on O/Cu(111) resulted predominantly in acetaldehyde formation via the dehydrogenation pathway, with lesser amounts of ethylene via dehydration, as well as combustion products. Successive TPRS experiments resulted in decreased yields of all products due to the consumption of surface oxygen via water formation <200 K. Isotopic studies of ethanol–OD indicate the role of the hydroxyl hydrogen in water formation from O<sub>ads</sub> compared to water that desorbs during dehydration, as well as hydrogen formation via the dehydrogenation pathway. The dehydration pathway is proposed to occur via autocatalytic production of O<sub>ads</sub> during the ethoxy transformation to ethylene, furthering the reaction to form ethylene and CO<sub>2</sub>.</div></div>","PeriodicalId":22100,"journal":{"name":"Surface Science","volume":"755 ","pages":"Article 122699"},"PeriodicalIF":2.1,"publicationDate":"2025-01-18","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143093381","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"化学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2025-01-16DOI: 10.1016/j.susc.2025.122698
Shupei Yin , Siya Deng , Chengyan Li , Yang Yue , Guangren Qian , Jia Zhang
A key problem of the catalytic oxidisation of nitrogen-containing volatile organic compounds (NVOCs) is to regulate the redox property of the catalyst. A too low oxidability results in low conversion; however, a too high oxidability produces undesired by-products such as N2O and NOx. In this study, Ce, Cu, Mn and V were loaded on TiO2 and applied in the catalytic oxidisation of acrylonitrile. Results revealed that Ce-doped TiO2 simultaneously showed better conversion (99 %) and N2 selectivity (95.3 %) than the other catalysts at 210 °C. However, the high selectivity was swiftly decreased to 74.5 % at 240 °C. After co-doping of Cu, the high selectivity was maintained above 89.8 % within 210 °C–270 °C. Meanwhile, catalytic conversions were close to 100 %. These ensured a stable catalytic performance even when the catalytic temperature was unusually high due to NVOC catalytic burning. Surface chemistry analyses showed that the redox potential of Ce-doped TiO2 was restrained after Cu doping, thus resulting in stable high N2 selectivity. This study presents a successful example of redox regulation by combining transition metals with different oxidabilities, which would develop more suitable catalysts for pollutants with unique catalytic requirements.
{"title":"Regulating the redox of a bimetallic catalyst for synchronous enhancement of acrylonitrile conversion and N2 selectivity","authors":"Shupei Yin , Siya Deng , Chengyan Li , Yang Yue , Guangren Qian , Jia Zhang","doi":"10.1016/j.susc.2025.122698","DOIUrl":"10.1016/j.susc.2025.122698","url":null,"abstract":"<div><div>A key problem of the catalytic oxidisation of nitrogen-containing volatile organic compounds (NVOCs) is to regulate the redox property of the catalyst. A too low oxidability results in low conversion; however, a too high oxidability produces undesired by-products such as N<sub>2</sub>O and NO<sub>x</sub>. In this study, Ce, Cu, Mn and V were loaded on TiO<sub>2</sub> and applied in the catalytic oxidisation of acrylonitrile. Results revealed that Ce-doped TiO<sub>2</sub> simultaneously showed better conversion (99 %) and N<sub>2</sub> selectivity (95.3 %) than the other catalysts at 210 °C. However, the high selectivity was swiftly decreased to 74.5 % at 240 °C. After co-doping of Cu, the high selectivity was maintained above 89.8 % within 210 °C–270 °C. Meanwhile, catalytic conversions were close to 100 %. These ensured a stable catalytic performance even when the catalytic temperature was unusually high due to NVOC catalytic burning. Surface chemistry analyses showed that the redox potential of Ce-doped TiO<sub>2</sub> was restrained after Cu doping, thus resulting in stable high N<sub>2</sub> selectivity. This study presents a successful example of redox regulation by combining transition metals with different oxidabilities, which would develop more suitable catalysts for pollutants with unique catalytic requirements.</div></div>","PeriodicalId":22100,"journal":{"name":"Surface Science","volume":"754 ","pages":"Article 122698"},"PeriodicalIF":2.1,"publicationDate":"2025-01-16","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143151037","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"化学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2025-01-14DOI: 10.1016/j.susc.2025.122697
Miaomiao Lou , Guili Liu , Meng Xu , Yuan Liu , Guoying Zhang
The geometric structure, stability, electronic structure and optical properties of the pristine SnSe2 and C-doped SnSe2 systems under tensile strain were computed using first principles. The findings indicate that the Sn-Se bond of the C-doped SnSe2 system is longer than that of the pristine SnSe2 system under the same tensile strain, and all systems in the low strain range can be stably formed. The electronic structure indicates that pristine SnSe2 is an indirect bandgap semiconductor. Under the action of tensile strain, the introduction of C atoms leads to a transformation of the band gap type. The valence band of the C-doped SnSe2 system is mainly attributed to the Se-4p and Sn-5p orbitals, while the conduction band is primarily assigned by Se-4p, Sn-5s and C-2p orbitals.The optical properties show that the peaks of ε1(ω) and ε2(ω) of both the pristine and doped systems are red-shifted under tensile strain, and the dielectric function ε2(ω), absorption and reflection peaks of the doped system are lower than those of the pristine system, indicating that the introduction of C atoms can effectively improve the conductivity of the materials. Meanwhile, the absorption peak of the doped system was blue-shifted to the high-energy region relative to that of the pristine system. Under the action of tensile strain, the reflection peak of the pristine SnSe2 system is redshifted, indicating that the tensile strain improves the utilization rate of the SnSe2 system for ultraviolet light and can be used as an excellent alternative material for ultraviolet light detectors.
{"title":"Effect of tensile strain on photoelectric properties of C-doped SnSe2 system","authors":"Miaomiao Lou , Guili Liu , Meng Xu , Yuan Liu , Guoying Zhang","doi":"10.1016/j.susc.2025.122697","DOIUrl":"10.1016/j.susc.2025.122697","url":null,"abstract":"<div><div>The geometric structure, stability, electronic structure and optical properties of the pristine SnSe<sub>2</sub> and C-doped SnSe<sub>2</sub> systems under tensile strain were computed using first principles. The findings indicate that the Sn-Se bond of the C-doped SnSe<sub>2</sub> system is longer than that of the pristine SnSe<sub>2</sub> system under the same tensile strain, and all systems in the low strain range can be stably formed. The electronic structure indicates that pristine SnSe<sub>2</sub> is an indirect bandgap semiconductor. Under the action of tensile strain, the introduction of C atoms leads to a transformation of the band gap type. The valence band of the C-doped SnSe<sub>2</sub> system is mainly attributed to the Se-4p and Sn-5p orbitals, while the conduction band is primarily assigned by Se-4p, Sn-5s and C-2p orbitals.The optical properties show that the peaks of ε<sub>1</sub>(ω) and ε<sub>2</sub>(ω) of both the pristine and doped systems are red-shifted under tensile strain, and the dielectric function ε<sub>2</sub>(ω), absorption and reflection peaks of the doped system are lower than those of the pristine system, indicating that the introduction of C atoms can effectively improve the conductivity of the materials. Meanwhile, the absorption peak of the doped system was blue-shifted to the high-energy region relative to that of the pristine system. Under the action of tensile strain, the reflection peak of the pristine SnSe<sub>2</sub> system is redshifted, indicating that the tensile strain improves the utilization rate of the SnSe<sub>2</sub> system for ultraviolet light and can be used as an excellent alternative material for ultraviolet light detectors.</div></div>","PeriodicalId":22100,"journal":{"name":"Surface Science","volume":"754 ","pages":"Article 122697"},"PeriodicalIF":2.1,"publicationDate":"2025-01-14","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143151035","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"化学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2025-01-13DOI: 10.1016/j.susc.2025.122696
Georg Held
Of all experimental Surface Science techniques, LEED-IV surface crystallography delivers the most complete set of crystallographic data for the near-surface regions (down to Å below the surface) of ordered single crystal surfaces. In the last five decades a large number of surface structures have been determined but theoretical and experimental procedures need to be adopted to meet the requirements of new directions in Surface Science. In this perspective article approaches will be discussed for extracting structural information from disordered and rough surfaces, increasing the experimental data set for large unit cells with complex unit cells, improving the scattering potentials used to calculate LEED-IV curves, and expanding the pressure range of the technique.
{"title":"Structure determination by low-energy electron diffraction—A roadmap to the future","authors":"Georg Held","doi":"10.1016/j.susc.2025.122696","DOIUrl":"10.1016/j.susc.2025.122696","url":null,"abstract":"<div><div>Of all experimental Surface Science techniques, LEED-IV surface crystallography delivers the most complete set of crystallographic data for the near-surface regions (down to <span><math><mrow><mo>≈</mo><mn>10</mn></mrow></math></span> Å below the surface) of ordered single crystal surfaces. In the last five decades a large number of surface structures have been determined but theoretical and experimental procedures need to be adopted to meet the requirements of new directions in Surface Science. In this perspective article approaches will be discussed for extracting structural information from disordered and rough surfaces, increasing the experimental data set for large unit cells with complex unit cells, improving the scattering potentials used to calculate LEED-IV curves, and expanding the pressure range of the technique.</div></div>","PeriodicalId":22100,"journal":{"name":"Surface Science","volume":"754 ","pages":"Article 122696"},"PeriodicalIF":2.1,"publicationDate":"2025-01-13","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143151724","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"化学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}