Pub Date : 2024-12-16DOI: 10.1021/acscatal.4c05857
Jaeyoung Yoo, Jungwoo Choi, Suyeon Choi, Changsoo Lee, Hyuck Mo Lee
Ammonia (NH3) is emerging as a promising carbon-free chemical energy source, offering higher storage capacity per unit volume compared to hydrogen and enhanced ease of liquefaction. This makes NH3 suitable for long-distance transportation and various industrial applications. The ammonia oxidation reaction (AOR) is crucial for electrochemically converting NH3 into H2, but current AOR catalysts face commercialization challenges due to cost and efficiency issues. This study explores ways to enhance AOR catalysts through a combined theoretical and experimental approach, focusing on Pt3X (where X represents screening elements) alloys. Density functional theory calculations were employed to analyze the AOR mechanism on Pt(111), (110), and (100) surfaces, identifying descriptors that facilitated the high-throughput screening of Pt3X alloys with (111), (110), and (100) facets for the highest AOR activity. The selected Pt3M (M = Fe, Co, and Ni) alloys were synthesized and characterized, revealing well-defined cubic shapes and superior AOR properties compared to pure Pt. Experimental results confirmed that Pt3Fe and Pt3Co nanocubes exhibit enhanced AOR activity and stability, aligning with theoretical predictions. This integrated approach highlights the potential of Pt3M alloys as cost-effective and efficient AOR catalysts, advancing ammonia electrolysis technologies for hydrogen production.
{"title":"Facet-Controlled Pt3M Alloys as Enhanced Catalysts for Ammonia Oxidation Reaction: A Combined Theoretical and Experimental Study","authors":"Jaeyoung Yoo, Jungwoo Choi, Suyeon Choi, Changsoo Lee, Hyuck Mo Lee","doi":"10.1021/acscatal.4c05857","DOIUrl":"https://doi.org/10.1021/acscatal.4c05857","url":null,"abstract":"Ammonia (NH<sub>3</sub>) is emerging as a promising carbon-free chemical energy source, offering higher storage capacity per unit volume compared to hydrogen and enhanced ease of liquefaction. This makes NH<sub>3</sub> suitable for long-distance transportation and various industrial applications. The ammonia oxidation reaction (AOR) is crucial for electrochemically converting NH<sub>3</sub> into H<sub>2</sub>, but current AOR catalysts face commercialization challenges due to cost and efficiency issues. This study explores ways to enhance AOR catalysts through a combined theoretical and experimental approach, focusing on Pt<sub>3</sub>X (where X represents screening elements) alloys. Density functional theory calculations were employed to analyze the AOR mechanism on Pt(111), (110), and (100) surfaces, identifying descriptors that facilitated the high-throughput screening of Pt<sub>3</sub>X alloys with (111), (110), and (100) facets for the highest AOR activity. The selected Pt<sub>3</sub>M (M = Fe, Co, and Ni) alloys were synthesized and characterized, revealing well-defined cubic shapes and superior AOR properties compared to pure Pt. Experimental results confirmed that Pt<sub>3</sub>Fe and Pt<sub>3</sub>Co nanocubes exhibit enhanced AOR activity and stability, aligning with theoretical predictions. This integrated approach highlights the potential of Pt<sub>3</sub>M alloys as cost-effective and efficient AOR catalysts, advancing ammonia electrolysis technologies for hydrogen production.","PeriodicalId":9,"journal":{"name":"ACS Catalysis ","volume":"22 1","pages":""},"PeriodicalIF":12.9,"publicationDate":"2024-12-16","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142825757","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"RegionCategory":"化学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
The rational design of highly efficient Co–Fe bimetallic catalysts is highly desirable for CO2 hydrogenation to olefins as an important alternative for traditional petroleum cracking technology. The treatment of carburization to construct the active phases stands out. Herein, the composition of active CoFe alloy carbide catalysts consisting of χ-(CoxFe1–x)5C2 and θ-(CoxFe1–x)3C phases was fine-tuned by altering the carburization environment. The synergistic effect between the dual components was optimized to improve the CO2 activation and C–C coupling capacity. The appropriate carburization degree and phase composition of CoFe alloy carbides are favorable for enhancing the space-time yield (STY) of C2+ olefins, up to 328.1 mg gcat–1 h–1 on the CoFe catalyst carburized in H2/CO = 2 at 320 °C for 8 h. This work provides useful guidelines for regulating product distribution in the design and synthesis of highly efficient catalysts.
{"title":"Fine-Tuning the Active Phases of CoFe Alloy Carbides for Boosting Olefin Synthesis from CO2 Hydrogenation","authors":"Na Liu, Qixin Fan, Jian Wei, Guanghui Zhang, Jian Sun, Wenhui Li, Chunshan Song, Xinwen Guo","doi":"10.1021/acscatal.4c06112","DOIUrl":"https://doi.org/10.1021/acscatal.4c06112","url":null,"abstract":"The rational design of highly efficient Co–Fe bimetallic catalysts is highly desirable for CO<sub>2</sub> hydrogenation to olefins as an important alternative for traditional petroleum cracking technology. The treatment of carburization to construct the active phases stands out. Herein, the composition of active CoFe alloy carbide catalysts consisting of χ-(Co<sub><i>x</i></sub>Fe<sub>1–<i>x</i></sub>)<sub>5</sub>C<sub>2</sub> and θ-(Co<sub><i>x</i></sub>Fe<sub>1–<i>x</i></sub>)<sub>3</sub>C phases was fine-tuned by altering the carburization environment. The synergistic effect between the dual components was optimized to improve the CO<sub>2</sub> activation and C–C coupling capacity. The appropriate carburization degree and phase composition of CoFe alloy carbides are favorable for enhancing the space-time yield (STY) of C<sub>2+</sub> olefins, up to 328.1 mg g<sub>cat</sub><sup>–1</sup> h<sup>–1</sup> on the CoFe catalyst carburized in H<sub>2</sub>/CO = 2 at 320 °C for 8 h. This work provides useful guidelines for regulating product distribution in the design and synthesis of highly efficient catalysts.","PeriodicalId":9,"journal":{"name":"ACS Catalysis ","volume":"16 1","pages":""},"PeriodicalIF":12.9,"publicationDate":"2024-12-16","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142825610","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"RegionCategory":"化学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2024-12-16DOI: 10.1021/acscatal.4c05744
Hengyu Li, Yangfan Shao, Zhichao Zhang, Muhammad N. Tahir, Tingzheng Hou, Lin Gan, Feng Ding, Jia Li
Metal–nitrogen–carbon (M–N–C) single-atom catalysts (SACs) have emerged as promising heterogeneous electrocatalysts for the CO2 reduction reaction (CO2RR). However, the predominant production of CO over multielectron products remains a challenge for most M–N–C SACs, with the exception of cobalt phthalocyanine (CoPc). In this study, the comparison of CoPc and a series of analogous M–N–C SACs was systematically investigated using density functional theory calculations to unravel the factors contributing to the selectivity of CoPc in catalyzing multielectron CO2RR. The relationship between the selectivity and the electronic configuration of M–N–C SACs was revealed. The half-filled dz2 orbital of the cobalt ion lead to moderate chemisorption of *CO on CoPc, enabling the subsequent protonation of *CO. In addition, we identified a unique type of hydrogen bond in which the C atom of *CO acts as the proton acceptor (C···H–O hydrogen bond), which significantly promotes the proton transfer to *CO and selectivity for multielectron products. Only the *CO on CoPc was observed to form the C···H–O hydrogen bond, elucidating the unique multielectron CO2RR performance of CoPc. In addition, we further elucidated the formation mechanism of the C···H–O hydrogen bond, which provides an alternative strategy to accelerate proton transfer in electrochemical reactions by utilizing this unconventional hydrogen bond.
{"title":"Understanding the Unique Selectivity of Cobalt Phthalocyanine in Multielectron Reduction of Carbon Dioxide","authors":"Hengyu Li, Yangfan Shao, Zhichao Zhang, Muhammad N. Tahir, Tingzheng Hou, Lin Gan, Feng Ding, Jia Li","doi":"10.1021/acscatal.4c05744","DOIUrl":"https://doi.org/10.1021/acscatal.4c05744","url":null,"abstract":"Metal–nitrogen–carbon (M–N–C) single-atom catalysts (SACs) have emerged as promising heterogeneous electrocatalysts for the CO<sub>2</sub> reduction reaction (CO<sub>2</sub>RR). However, the predominant production of CO over multielectron products remains a challenge for most M–N–C SACs, with the exception of cobalt phthalocyanine (CoPc). In this study, the comparison of CoPc and a series of analogous M–N–C SACs was systematically investigated using density functional theory calculations to unravel the factors contributing to the selectivity of CoPc in catalyzing multielectron CO<sub>2</sub>RR. The relationship between the selectivity and the electronic configuration of M–N–C SACs was revealed. The half-filled d<sub><i>z</i><sup>2</sup></sub> orbital of the cobalt ion lead to moderate chemisorption of *CO on CoPc, enabling the subsequent protonation of *CO. In addition, we identified a unique type of hydrogen bond in which the C atom of *CO acts as the proton acceptor (C···H–O hydrogen bond), which significantly promotes the proton transfer to *CO and selectivity for multielectron products. Only the *CO on CoPc was observed to form the C···H–O hydrogen bond, elucidating the unique multielectron CO<sub>2</sub>RR performance of CoPc. In addition, we further elucidated the formation mechanism of the C···H–O hydrogen bond, which provides an alternative strategy to accelerate proton transfer in electrochemical reactions by utilizing this unconventional hydrogen bond.","PeriodicalId":9,"journal":{"name":"ACS Catalysis ","volume":"39 1","pages":""},"PeriodicalIF":12.9,"publicationDate":"2024-12-16","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142825607","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"RegionCategory":"化学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2024-12-16DOI: 10.1021/acscatal.4c05954
Jiajia Wang, Zhuodong Ou, Chengbo Dong, Mengying Su, Amjad Ali, Artem V. Kuklin, Hans Ågren, Glib V. Baryshnikov, Yang Liu, Xue Zhao, Haibo Zhang
Electrocatalytic nitrate reduction for ammonia (eNIRR) is an ammonia production process that simultaneously removes nitrate contaminants from water. However, the lack of activity of cathode catalysts used as eNIRR catalysts is the main limiting factor for its development. Motivated by this fact, born-doped copper (BDCu) was obtained by using ZnO, which was easily removed at high temperature, as a dispersant, combined with weakly reducing boron clusters (closo-[B12H12]2–) as a reducing agent and B source during high-temperature pyrolysis. Impressively, BDCu demonstrated a Faradaic efficiency of 96.58% and a yield rate of 25741.51 μg h–1 mgcat–1 toward ammonia production at −1.8 V (vs saturated calomel electrode). The ammonia yield rate of BDCu was twice as high as in the case of undoped B. Evolutionary behavior of NO3– to NH3 conversion detected by in situ Fourier-transform infrared (in situ FT-IR) and electrochemical in situ mass spectrometry (in situ DEMS). Experimental and density functional theory (DFT) calculations explained that the activation of water was enhanced by B-doped Cu, and the adsorption of proton *H was weakened, which made it easy for *H to migrate away from the catalyst to NO3– as a proton required for NO3– reduction. In addition, the electron-deficient of B provides conditions for electron transfer between B and Cu. The electron transfer from Cu to B in BDCu led to a decrease in the center of the d-band of Cu, which modulated the electronic properties of Cu and altered the behavior of the NO3– to NH3 transition on the Cu surface. Compared with Cu undoped B as well as unreduced CuO, BDCu lowered the energy barrier of the rate-determining step (*NO → *N), allowing for a smoother conversion of NO3– to NH3. This study provides a strategy to change the electronic structure of transition metals by B-modification and thus improve the performance of ammonia synthesis.
电催化硝酸盐还原法制氨（eNIRR）是一种同时去除水中硝酸盐污染物的制氨工艺。然而，用作 eNIRR 催化剂的阴极催化剂缺乏活性是限制其发展的主要因素。受这一事实的启发，在高温热解过程中，使用在高温下易于去除的氧化锌作为分散剂，结合弱还原性硼团簇（closo-[B12H12]2-）作为还原剂和硼源，获得了天生掺杂铜（BDCu）。令人印象深刻的是，BDCu 的法拉第效率高达 96.58%，在 -1.8 V（相对于饱和甘汞电极）电压下的氨生产产率为 25741.51 μg h-1 mgcat-1。通过原位傅立叶变换红外光谱（in situ FT-IR）和电化学原位质谱法（in situ DEMS）检测了 NO3- 向 NH3 转化的演化过程。实验和密度泛函理论（DFT）计算表明，掺杂 B 的 Cu 增强了水的活化，减弱了质子 *H 的吸附，使 *H 易于从催化剂迁移到 NO3-，成为 NO3-还原所需的质子。此外，B 的缺电子特性也为 B 和 Cu 之间的电子转移提供了条件。BDCu 中从 Cu 到 B 的电子转移导致 Cu 的 d 带中心下降，从而调节了 Cu 的电子特性，改变了 Cu 表面 NO3- 到 NH3 转变的行为。与未掺杂 B 的 Cu 以及未还原的 CuO 相比，BDCu 降低了决定速率步骤（*NO → *N）的能障，从而使 NO3- 向 NH3 的转化更加平稳。这项研究为通过 B 修饰改变过渡金属的电子结构，从而改善氨合成的性能提供了一种策略。
{"title":"Electronic Structure Modulated by B-Doped Cu Promotes Electrocatalytic Nitrate Reduction for Ammonia Production","authors":"Jiajia Wang, Zhuodong Ou, Chengbo Dong, Mengying Su, Amjad Ali, Artem V. Kuklin, Hans Ågren, Glib V. Baryshnikov, Yang Liu, Xue Zhao, Haibo Zhang","doi":"10.1021/acscatal.4c05954","DOIUrl":"https://doi.org/10.1021/acscatal.4c05954","url":null,"abstract":"Electrocatalytic nitrate reduction for ammonia (eNIRR) is an ammonia production process that simultaneously removes nitrate contaminants from water. However, the lack of activity of cathode catalysts used as eNIRR catalysts is the main limiting factor for its development. Motivated by this fact, born-doped copper (BDCu) was obtained by using ZnO, which was easily removed at high temperature, as a dispersant, combined with weakly reducing boron clusters (<i>closo</i>-[B<sub>12</sub>H<sub>12</sub>]<sup>2–</sup>) as a reducing agent and B source during high-temperature pyrolysis. Impressively, BDCu demonstrated a Faradaic efficiency of 96.58% and a yield rate of 25741.51 μg h<sup>–1</sup> mg<sub>cat</sub><sup>–1</sup> toward ammonia production at −1.8 V (vs saturated calomel electrode). The ammonia yield rate of BDCu was twice as high as in the case of undoped B. Evolutionary behavior of NO<sub>3</sub><sup>–</sup> to NH<sub>3</sub> conversion detected by in situ Fourier-transform infrared (in situ FT-IR) and electrochemical in situ mass spectrometry (in situ DEMS). Experimental and density functional theory (DFT) calculations explained that the activation of water was enhanced by B-doped Cu, and the adsorption of proton *H was weakened, which made it easy for *H to migrate away from the catalyst to NO<sub>3</sub><sup>–</sup> as a proton required for NO<sub>3</sub><sup>–</sup> reduction. In addition, the electron-deficient of B provides conditions for electron transfer between B and Cu. The electron transfer from Cu to B in BDCu led to a decrease in the center of the d-band of Cu, which modulated the electronic properties of Cu and altered the behavior of the NO<sub>3</sub><sup>–</sup> to NH<sub>3</sub> transition on the Cu surface. Compared with Cu undoped B as well as unreduced CuO, BDCu lowered the energy barrier of the rate-determining step (*NO → *N), allowing for a smoother conversion of NO<sub>3</sub><sup>–</sup> to NH<sub>3</sub>. This study provides a strategy to change the electronic structure of transition metals by B-modification and thus improve the performance of ammonia synthesis.","PeriodicalId":9,"journal":{"name":"ACS Catalysis ","volume":"34 1","pages":""},"PeriodicalIF":12.9,"publicationDate":"2024-12-16","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142825609","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"RegionCategory":"化学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2024-12-16DOI: 10.1021/acscatal.4c05763
Mingjun Lv, Xinhui Yu, Jitian Liu, Xiaoxun Li
The catalytic asymmetric synthesis of functionalized C2-quaternary indoline scaffolds has garnered significant attention in organic synthesis and drug discovery due to the inherent challenges and potential applications. Herein, we present a facile approach utilizing a Pd-catalyzed intramolecular decarboxylative asymmetric amination of vinyl benzoxazepinones, leading to the efficient construction of challenging chiral 2-vinyl-2-aryl/alkyl indoline frameworks in good yields with high enantioselectivities (>50 examples, up to 83% yield and 97% ee). Furthermore, these chiral indolines can be readily scaled up and further modified to access complex polycyclic indoline structures. We also synthesized several indoline-based ligands that exhibit promising efficiency as chiral catalysts in asymmetric reactions. Computational studies provided insight into the inner-sphere asymmetric amination mechanism.
{"title":"Construction of Chiral C2-Quaternary Indolines via Palladium-Catalyzed Decarboxylative Asymmetric Amination","authors":"Mingjun Lv, Xinhui Yu, Jitian Liu, Xiaoxun Li","doi":"10.1021/acscatal.4c05763","DOIUrl":"https://doi.org/10.1021/acscatal.4c05763","url":null,"abstract":"The catalytic asymmetric synthesis of functionalized C2-quaternary indoline scaffolds has garnered significant attention in organic synthesis and drug discovery due to the inherent challenges and potential applications. Herein, we present a facile approach utilizing a Pd-catalyzed intramolecular decarboxylative asymmetric amination of vinyl benzoxazepinones, leading to the efficient construction of challenging chiral 2-vinyl-2-aryl/alkyl indoline frameworks in good yields with high enantioselectivities (>50 examples, up to 83% yield and 97% ee). Furthermore, these chiral indolines can be readily scaled up and further modified to access complex polycyclic indoline structures. We also synthesized several indoline-based ligands that exhibit promising efficiency as chiral catalysts in asymmetric reactions. Computational studies provided insight into the inner-sphere asymmetric amination mechanism.","PeriodicalId":9,"journal":{"name":"ACS Catalysis ","volume":"35 1","pages":""},"PeriodicalIF":12.9,"publicationDate":"2024-12-16","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142832606","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"RegionCategory":"化学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2024-12-16DOI: 10.1021/acscatal.4c03543
Jun Ki Yoo, Seok-Ho Lee, Tae In Park, Jun Hong Lee, Kwan-Young Lee
Liquid organic hydrogen carriers (LOHCs) are promising materials for hydrogen storage due to their convenient and stable physical properties. Recent studies have focused on benzyltoluene for its favorable properties; however, its low efficiency in hydrogenation and dehydrogenation processes limits its applicability. Therefore, an approach to overcoming this challenge through catalysis is necessary. In this study, Pt/Al2O3 catalysts promoted with Nb (Pt–Nb) exhibited enhanced activity and selectivity in both hydrogenation and dehydrogenation of benzyltoluene (optimal at 5 wt % Nb). The selective blocking of hyperactive undercoordinated Pt sites by niobium oxide played a crucial role in enhancing the selectivity and stability. Additionally, the electron-withdrawing effect and increased occurrence of hydrogen spillover resulting from its acidic properties could modify the interaction with the hydrogen. Notably, the introduction of the niobium promoter seems to create additional adsorption sites for hydrogen, thereby enhancing the efficiency of LOHC molecules to bind on the Pt surface. It was discovered that the terrace sites of Pt catalysts could act as gathering points for reverse-spillover hydrogen during LOHC reactions. Therefore, when promoted with Nb, the active Pt terrace sites become capable of efficiently adsorbing LOHC molecules while simultaneously serving as sites for reaction with returning hydrogen. In summary, the addition of the niobium promoter elevates the efficiency of the platinum terrace, which serves as the active site, while suppressing the adverse effects of undercoordinated Pt sites. However, the growth of NbOx with increasing Nb content blocks the active terrace Pt sites, underscoring the need for appropriate optimization processes.
{"title":"Unraveling the Impact of Niobia Promotion on Pt/Al2O3 for Enhanced Catalytic Performance in Benzyltoluene Reactions","authors":"Jun Ki Yoo, Seok-Ho Lee, Tae In Park, Jun Hong Lee, Kwan-Young Lee","doi":"10.1021/acscatal.4c03543","DOIUrl":"https://doi.org/10.1021/acscatal.4c03543","url":null,"abstract":"Liquid organic hydrogen carriers (LOHCs) are promising materials for hydrogen storage due to their convenient and stable physical properties. Recent studies have focused on benzyltoluene for its favorable properties; however, its low efficiency in hydrogenation and dehydrogenation processes limits its applicability. Therefore, an approach to overcoming this challenge through catalysis is necessary. In this study, Pt/Al<sub>2</sub>O<sub>3</sub> catalysts promoted with Nb (Pt–Nb) exhibited enhanced activity and selectivity in both hydrogenation and dehydrogenation of benzyltoluene (optimal at 5 wt % Nb). The selective blocking of hyperactive undercoordinated Pt sites by niobium oxide played a crucial role in enhancing the selectivity and stability. Additionally, the electron-withdrawing effect and increased occurrence of hydrogen spillover resulting from its acidic properties could modify the interaction with the hydrogen. Notably, the introduction of the niobium promoter seems to create additional adsorption sites for hydrogen, thereby enhancing the efficiency of LOHC molecules to bind on the Pt surface. It was discovered that the terrace sites of Pt catalysts could act as gathering points for reverse-spillover hydrogen during LOHC reactions. Therefore, when promoted with Nb, the active Pt terrace sites become capable of efficiently adsorbing LOHC molecules while simultaneously serving as sites for reaction with returning hydrogen. In summary, the addition of the niobium promoter elevates the efficiency of the platinum terrace, which serves as the active site, while suppressing the adverse effects of undercoordinated Pt sites. However, the growth of NbO<sub><i>x</i></sub> with increasing Nb content blocks the active terrace Pt sites, underscoring the need for appropriate optimization processes.","PeriodicalId":9,"journal":{"name":"ACS Catalysis ","volume":"106 1","pages":""},"PeriodicalIF":12.9,"publicationDate":"2024-12-16","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142825755","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"RegionCategory":"化学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2024-12-16DOI: 10.1021/acscatal.4c06189
Lanke Luo, Mingxuan Li, Haohai Dong, Haomin Jiang, Huatian Chen, Jiongjun Wu, Peiyuan Su, Xinyue Zhang, Lin Chen, Zemin Sun, Liu Lin
Electrochemical two-electron water oxidation (2e– WOR) represents a promising approach for the renewable and on-site production of H2O2, potentially replacing the anthraquinone process. Nevertheless, it faces intense competition from the conventional four-electron oxygen evolution reaction (OER), resulting in low selectivity, high overpotential, and low yield. Herein, taking carbon-based structures with 2e– WOR selectivity as model catalysts, by manipulating the electrolyte, it increased the maximum Faraday efficiency of H2O2 to 71 ± 3%, with an H2O2 production rate of 11.7 μmol cm–2 min–1. The 2e– WOR activity was found to be most sensitive to alkali metal cations in the following order: Cs+ > K+ > Na+ > Li+. In situ spectroscopy characterization confirmed that larger cations facilitate the generation of peroxide species; this is because, on one hand, cations can regulate the electronic activity of the catalyst sites and improve the adsorption of the reaction intermediates; on the other hand, the cation-hydrogen oxygen interaction regulates the stable coordination of the cation, realizes the reforming of the hydrogen bond network, and prevents its further water oxidation into O2. With the help of a flow electro-synthetic cell, we can successfully achieve the rapid degradation of organic pollutants in water and the preparation of solid H2O2 (sodium peroxycarbonate). This work not only enriches the understanding of cationic and 2e– WOR mechanisms but also provides implications for rational optimization strategies of the electrode/electrolyte interface.
{"title":"Manipulating Metal Cations Microenvironment for Highly Selective Electrochemical Water Oxidation to Hydrogen Peroxide","authors":"Lanke Luo, Mingxuan Li, Haohai Dong, Haomin Jiang, Huatian Chen, Jiongjun Wu, Peiyuan Su, Xinyue Zhang, Lin Chen, Zemin Sun, Liu Lin","doi":"10.1021/acscatal.4c06189","DOIUrl":"https://doi.org/10.1021/acscatal.4c06189","url":null,"abstract":"Electrochemical two-electron water oxidation (2e<sup>–</sup> WOR) represents a promising approach for the renewable and on-site production of H<sub>2</sub>O<sub>2</sub>, potentially replacing the anthraquinone process. Nevertheless, it faces intense competition from the conventional four-electron oxygen evolution reaction (OER), resulting in low selectivity, high overpotential, and low yield. Herein, taking carbon-based structures with 2e<sup>–</sup> WOR selectivity as model catalysts, by manipulating the electrolyte, it increased the maximum Faraday efficiency of H<sub>2</sub>O<sub>2</sub> to 71 ± 3%, with an H<sub>2</sub>O<sub>2</sub> production rate of 11.7 μmol cm<sup>–2</sup> min<sup>–1</sup>. The 2e<sup>–</sup> WOR activity was found to be most sensitive to alkali metal cations in the following order: Cs<sup>+</sup> > K<sup>+</sup> > Na<sup>+</sup> > Li<sup>+</sup>. In situ spectroscopy characterization confirmed that larger cations facilitate the generation of peroxide species; this is because, on one hand, cations can regulate the electronic activity of the catalyst sites and improve the adsorption of the reaction intermediates; on the other hand, the cation-hydrogen oxygen interaction regulates the stable coordination of the cation, realizes the reforming of the hydrogen bond network, and prevents its further water oxidation into O<sub>2</sub>. With the help of a flow electro-synthetic cell, we can successfully achieve the rapid degradation of organic pollutants in water and the preparation of solid H<sub>2</sub>O<sub>2</sub> (sodium peroxycarbonate). This work not only enriches the understanding of cationic and 2e<sup>–</sup> WOR mechanisms but also provides implications for rational optimization strategies of the electrode/electrolyte interface.","PeriodicalId":9,"journal":{"name":"ACS Catalysis ","volume":"10 1","pages":""},"PeriodicalIF":12.9,"publicationDate":"2024-12-16","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142825611","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"RegionCategory":"化学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2024-12-16DOI: 10.1021/acscatal.4c06720
Xilong Wang, Jiali Xu, Yu Luo, Yuanyu Wang, Jun Huang, Qiang Zhu, Shuang Luo
On the basis of density functional theory (DFT) calculations, we designed an asymmetric synthesis method for axially chiral biaryls through C(sp2)–H imidoylative cyclization of isocyanides. Building on this, we successfully synthesized axially chiral compounds containing indole-fused N-heteroaromatic frameworks via palladium-catalyzed C–H imidoylation to achieve high yields and enantioselectivity. Various efficient cyclization pathways facilitated the synthesis of indole-fused ring derivatives with either C–C or C–N axial chirality. This not only provides an efficient and diverse strategy for the synthesis of axially chiral compounds but also demonstrates that DFT-assisted design is a reliable tool for accurately predicting reaction stereoselectivity and effectively reducing the workload of chemical experiments.
{"title":"DFT-Assisted Atroposelective Construction of Indole-Fused N-Heteroaromatic Frameworks through Palladium-Catalyzed C–H Imidoylation","authors":"Xilong Wang, Jiali Xu, Yu Luo, Yuanyu Wang, Jun Huang, Qiang Zhu, Shuang Luo","doi":"10.1021/acscatal.4c06720","DOIUrl":"https://doi.org/10.1021/acscatal.4c06720","url":null,"abstract":"On the basis of density functional theory (DFT) calculations, we designed an asymmetric synthesis method for axially chiral biaryls through C(sp<sup>2</sup>)–H imidoylative cyclization of isocyanides. Building on this, we successfully synthesized axially chiral compounds containing indole-fused <i>N</i>-heteroaromatic frameworks via palladium-catalyzed C–H imidoylation to achieve high yields and enantioselectivity. Various efficient cyclization pathways facilitated the synthesis of indole-fused ring derivatives with either C–C or C–N axial chirality. This not only provides an efficient and diverse strategy for the synthesis of axially chiral compounds but also demonstrates that DFT-assisted design is a reliable tool for accurately predicting reaction stereoselectivity and effectively reducing the workload of chemical experiments.","PeriodicalId":9,"journal":{"name":"ACS Catalysis ","volume":"30 1","pages":""},"PeriodicalIF":12.9,"publicationDate":"2024-12-16","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142825612","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"RegionCategory":"化学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2024-12-16DOI: 10.1021/acscatal.4c05842
Ming-Yu Qi, Wei-Yun Xiao, Marco Conte, Zi-Rong Tang, Yi-Jun Xu
Semiconductor-based photocatalysis has evolved over the past decade into a prevalent approach for alcohol oxidation to afford the corresponding carbonyl compounds or C–C/C–O coupled products. Nonetheless, photocatalytic oxidative lactonization of diols to lactones still significantly lags behind, even though lactones represent a class of ring moieties with excellent biological activities. In this work, we present the high-performance visible-light-mediated lactonization of diols to lactones and H2 over the Ti3C2Tx MXene-supported CdS quantum dots (QDs) with Ni decoration (Ni/CdS/Ti3C2Tx). Ti3C2Tx acts as a two-dimensional platform for immobilizing CdS to promote the separation and migration of charge carriers, while concomitantly the Cd2+ confinement effect of Ti3C2Tx significantly retards the hole-induced photocorrosion of CdS. The unique modifications of atomically dispersed Ni species are either incorporated as Ni clusters in CdS to accelerate H2 evolution, or anchored as a Ni single atom on Ti3C2Tx for the efficient adsorption and cyclization of diols. The optimized Ni/CdS/Ti3C2Tx exhibits remarkably enhanced activity for lactone synthesis, which is 80.4 times higher than that of blank CdS, along with excellent selectivity and high durability. This work brings a conceptual idea to overcome the well-known intrinsic drawback of photoinduced decomposition in semiconductor-based photocatalysts and offers a generic and robust strategy of utilizing atomically dispersed cocatalyst as active sites for efficient and robust photoredox lactones synthesis and H2 evolution.
{"title":"Interfacial Synergy of Ni Single Atom/Clusters and MXene Enabling Semiconductor Quantum Dots Based Superior Photoredox Catalysis","authors":"Ming-Yu Qi, Wei-Yun Xiao, Marco Conte, Zi-Rong Tang, Yi-Jun Xu","doi":"10.1021/acscatal.4c05842","DOIUrl":"https://doi.org/10.1021/acscatal.4c05842","url":null,"abstract":"Semiconductor-based photocatalysis has evolved over the past decade into a prevalent approach for alcohol oxidation to afford the corresponding carbonyl compounds or C–C/C–O coupled products. Nonetheless, photocatalytic oxidative lactonization of diols to lactones still significantly lags behind, even though lactones represent a class of ring moieties with excellent biological activities. In this work, we present the high-performance visible-light-mediated lactonization of diols to lactones and H<sub>2</sub> over the Ti<sub>3</sub>C<sub>2</sub>T<sub><i>x</i></sub> MXene-supported CdS quantum dots (QDs) with Ni decoration (Ni/CdS/Ti<sub>3</sub>C<sub>2</sub>T<sub><i>x</i></sub>). Ti<sub>3</sub>C<sub>2</sub>T<sub><i>x</i></sub> acts as a two-dimensional platform for immobilizing CdS to promote the separation and migration of charge carriers, while concomitantly the Cd<sup>2+</sup> confinement effect of Ti<sub>3</sub>C<sub>2</sub>T<sub><i>x</i></sub> significantly retards the hole-induced photocorrosion of CdS. The unique modifications of atomically dispersed Ni species are either incorporated as Ni clusters in CdS to accelerate H<sub>2</sub> evolution, or anchored as a Ni single atom on Ti<sub>3</sub>C<sub>2</sub>T<sub><i>x</i></sub> for the efficient adsorption and cyclization of diols. The optimized Ni/CdS/Ti<sub>3</sub>C<sub>2</sub>T<sub><i>x</i></sub> exhibits remarkably enhanced activity for lactone synthesis, which is 80.4 times higher than that of blank CdS, along with excellent selectivity and high durability. This work brings a conceptual idea to overcome the well-known intrinsic drawback of photoinduced decomposition in semiconductor-based photocatalysts and offers a generic and robust strategy of utilizing atomically dispersed cocatalyst as active sites for efficient and robust photoredox lactones synthesis and H<sub>2</sub> evolution.","PeriodicalId":9,"journal":{"name":"ACS Catalysis ","volume":"253 1","pages":""},"PeriodicalIF":12.9,"publicationDate":"2024-12-16","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142825756","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"RegionCategory":"化学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Construction of the Schottky junction is a promising strategy for realizing efficient photocatalytic N2 fixation; however, the reported Schottky junction photocatalysts are mainly constructed via physical stacking or Van der Waals interaction with much room to improve performance. Herein, a chemically bonded Schottky junction photocatalyst is constructed for the fixation of N2 to NH3 production. The photocatalyst exhibits a unique 1D necklace-like morphology with hollow ZnCo bimetal sulfide (ZnCoSx) nanocages strung by carbon nanotubes (CNTs). Experimental and theoretical results reveal that the formation of C–O–Co chemical bonds at the interface not only provides an atomic transportation highway for charge transfer but also modulates the electronic structure of Co active sites toward enhanced N2 chemisorption and activation. The elaborately designed CNT/ZnCoSx junction with a chemically bonded interface exhibits superior nitrogen fixation activity with an NH3 yield of 1644 μmol g–1 h–1 in pure water. This study paves the way for the development of efficient Schottky junction photocatalysts for their applications.
{"title":"Chemically Bonded Schottky Junction for Efficient N2 Photofixation","authors":"Yin Bi, Yuan Fang, Ling Yuan, Jiaxin Li, Chaoqi Zhang, Pengyue Shan, Xinchan Zhang, Chao Liu, Chengzhong Yu","doi":"10.1021/acscatal.4c04443","DOIUrl":"https://doi.org/10.1021/acscatal.4c04443","url":null,"abstract":"Construction of the Schottky junction is a promising strategy for realizing efficient photocatalytic N<sub>2</sub> fixation; however, the reported Schottky junction photocatalysts are mainly constructed via physical stacking or Van der Waals interaction with much room to improve performance. Herein, a chemically bonded Schottky junction photocatalyst is constructed for the fixation of N<sub>2</sub> to NH<sub>3</sub> production. The photocatalyst exhibits a unique 1D necklace-like morphology with hollow ZnCo bimetal sulfide (ZnCoS<sub><i>x</i></sub>) nanocages strung by carbon nanotubes (CNTs). Experimental and theoretical results reveal that the formation of C–O–Co chemical bonds at the interface not only provides an atomic transportation highway for charge transfer but also modulates the electronic structure of Co active sites toward enhanced N<sub>2</sub> chemisorption and activation. The elaborately designed CNT/ZnCoS<sub><i>x</i></sub> junction with a chemically bonded interface exhibits superior nitrogen fixation activity with an NH<sub>3</sub> yield of 1644 μmol g<sup>–1</sup> h<sup>–1</sup> in pure water. This study paves the way for the development of efficient Schottky junction photocatalysts for their applications.","PeriodicalId":9,"journal":{"name":"ACS Catalysis ","volume":"20 1","pages":""},"PeriodicalIF":12.9,"publicationDate":"2024-12-16","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142832584","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"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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