Pub Date : 2024-08-22DOI: 10.1016/j.apcatb.2024.124516
Qingzheng Tian, Li Wang, Weiwei Sun, Alan Meng, Lina Yang, Zhenjiang Li
The industrial interest of ZnCdS as the photocatalytic media for hydrogen evolution reaction (HER) is severely hindered by its sluggish interfacial charge transfer, limited active sites, and serious photocorrosions. Herein, to catalyze more efficient and robust HER, a series of Se-doped ZnCdS with sulfur vacancies (denoted as Se/V-ZnCdS) are ingeniously designed and facilely synthesized. Experimental and theoretical studies reveal that by inducing dipole polarization through defect engineering synergistic elemental doping, spontaneous polarization field is generated in the bulk phase of ZnCdS, which together with elevated Fermi level renders the Se/V-ZnCdS with desirable spatial charge separation and transfer. Thus, the optimal 0.6 %Se/V-ZnCdS exhibits the outstanding performance of 85.3 mmol·g·h and excellent stability up to 24 h. This work highlights the high efficiency of dipole polarization realized by vacancy synergistic atomic doping in optimizing HER kinetics, and provides a new pathway to develop robust photocatalysts based on metal sulfoselenide for water-splitting reactions.
{"title":"Dipole polarization-driven spatial charge separation in defective zinc cadmium sulfoselenide for boosting photocatalytic hydrogen evolution","authors":"Qingzheng Tian, Li Wang, Weiwei Sun, Alan Meng, Lina Yang, Zhenjiang Li","doi":"10.1016/j.apcatb.2024.124516","DOIUrl":"https://doi.org/10.1016/j.apcatb.2024.124516","url":null,"abstract":"The industrial interest of ZnCdS as the photocatalytic media for hydrogen evolution reaction (HER) is severely hindered by its sluggish interfacial charge transfer, limited active sites, and serious photocorrosions. Herein, to catalyze more efficient and robust HER, a series of Se-doped ZnCdS with sulfur vacancies (denoted as Se/V-ZnCdS) are ingeniously designed and facilely synthesized. Experimental and theoretical studies reveal that by inducing dipole polarization through defect engineering synergistic elemental doping, spontaneous polarization field is generated in the bulk phase of ZnCdS, which together with elevated Fermi level renders the Se/V-ZnCdS with desirable spatial charge separation and transfer. Thus, the optimal 0.6 %Se/V-ZnCdS exhibits the outstanding performance of 85.3 mmol·g·h and excellent stability up to 24 h. This work highlights the high efficiency of dipole polarization realized by vacancy synergistic atomic doping in optimizing HER kinetics, and provides a new pathway to develop robust photocatalysts based on metal sulfoselenide for water-splitting reactions.","PeriodicalId":516528,"journal":{"name":"Applied Catalysis B: Environment and Energy","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2024-08-22","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142205172","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
The high hydrogen release temperature and thermodynamic stability of the coordination hydride LiAlH render it unsuitable for direct application. This work intends to improve the hydrogen release properties via compositing LiAlH and AlH with similar initial hydrogen release temperatures and introduce efficient additive Ni/CeO composite. The thermal stability of the composite system LiAlH-AlH is enormously reduced compared to that of LiAlH. In addition, the preferential release of hydrogen from LiAlH in the composite system provides additional heat for the subsequent release of hydrogen from AlH, accelerating the hydrogen release process. As a result, LiAlH-AlH-Ni/CeO composite performs enhanced hydrogen release performance with a hydrogen release capacity of 8.27 wt% hydrogen within 300 ℃ and a dehydrogenation onset temperature as low as 72.9 ℃. The enthalpy change of the first step hydrogen release reaction decreases from −11.99 kJ mol (LiAlH) to −2.02 kJ mol (LiAlH-AlH). Theoretical calculations indicate that both atomic dehybridisation and electron redistribution expedite the breaking of the Al-H bond and the consequent release of hydrogen.
{"title":"Constructing Ni/CeO2 synergistic catalysts into LiAlH4 and AlH3 composite for enhanced hydrogen released properties","authors":"Chunmin Zhang, Chunli Wang, Qingyun Shi, Xiaoli Wang, Shaolei Zhao, Long Liang, Qingshuang Wang, Limin Wang, Yong Cheng","doi":"10.1016/j.apcatb.2024.124521","DOIUrl":"https://doi.org/10.1016/j.apcatb.2024.124521","url":null,"abstract":"The high hydrogen release temperature and thermodynamic stability of the coordination hydride LiAlH render it unsuitable for direct application. This work intends to improve the hydrogen release properties via compositing LiAlH and AlH with similar initial hydrogen release temperatures and introduce efficient additive Ni/CeO composite. The thermal stability of the composite system LiAlH-AlH is enormously reduced compared to that of LiAlH. In addition, the preferential release of hydrogen from LiAlH in the composite system provides additional heat for the subsequent release of hydrogen from AlH, accelerating the hydrogen release process. As a result, LiAlH-AlH-Ni/CeO composite performs enhanced hydrogen release performance with a hydrogen release capacity of 8.27 wt% hydrogen within 300 ℃ and a dehydrogenation onset temperature as low as 72.9 ℃. The enthalpy change of the first step hydrogen release reaction decreases from −11.99 kJ mol (LiAlH) to −2.02 kJ mol (LiAlH-AlH). Theoretical calculations indicate that both atomic dehybridisation and electron redistribution expedite the breaking of the Al-H bond and the consequent release of hydrogen.","PeriodicalId":516528,"journal":{"name":"Applied Catalysis B: Environment and Energy","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2024-08-22","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142205137","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Low degradation efficiency and significant transition metal leaching are two challenges in persulfate activation systems based on metal-organic frameworks (MOFs) for organic pollutant degradation. Here, the challenges were solved by designing and synthesizing a micron-sized core-shell material, γ-AlO-C-MIL-100(Fe) (γACM), by coating the γ-AlO core with carbon (γ-AlO-C) and futher modifying with MIL-100(Fe). Testing γACM with sulfamethazine (SMZ) demonstrated its outstanding peroxydisulfate (PDS) activation, achieving 92.5 % SMZ removal within 20 min at a low oxidant/pollutant ratio. Fe leaching from γACM was effectively inhibited, with only 3.59 % Fe lost after three recycles. The system showed adaptability across a wide pH range, and usability in sewage effluent, indicating promise for practical application. The hydrophobicity of γ-AlO-C, the coordinatively unsaturated sites in MIL-100(Fe), and the strong bounding of MIL-100(Fe) on γ-AlO-C ensured the effective SMZ gather, PDS activation, and Fe stability respectively, which led to the excellent performances of γACM.
{"title":"Efficient peroxydisulfate activation with γ-Al2O3-C-MIL-100(Fe) framework for sulfamethazine degradation: Enhanced oxidant utilization and reduced metal leaching","authors":"Jianxin Zhu, Haiyang Liu, Haijun Chen, Xiuyi Hua, Deming Dong, Dapeng Liang, Zhiyong Guo, Na Zheng","doi":"10.1016/j.apcatb.2024.124520","DOIUrl":"https://doi.org/10.1016/j.apcatb.2024.124520","url":null,"abstract":"Low degradation efficiency and significant transition metal leaching are two challenges in persulfate activation systems based on metal-organic frameworks (MOFs) for organic pollutant degradation. Here, the challenges were solved by designing and synthesizing a micron-sized core-shell material, γ-AlO-C-MIL-100(Fe) (γACM), by coating the γ-AlO core with carbon (γ-AlO-C) and futher modifying with MIL-100(Fe). Testing γACM with sulfamethazine (SMZ) demonstrated its outstanding peroxydisulfate (PDS) activation, achieving 92.5 % SMZ removal within 20 min at a low oxidant/pollutant ratio. Fe leaching from γACM was effectively inhibited, with only 3.59 % Fe lost after three recycles. The system showed adaptability across a wide pH range, and usability in sewage effluent, indicating promise for practical application. The hydrophobicity of γ-AlO-C, the coordinatively unsaturated sites in MIL-100(Fe), and the strong bounding of MIL-100(Fe) on γ-AlO-C ensured the effective SMZ gather, PDS activation, and Fe stability respectively, which led to the excellent performances of γACM.","PeriodicalId":516528,"journal":{"name":"Applied Catalysis B: Environment and Energy","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2024-08-22","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142205173","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
The synthesis of valuable aromatics via CO transformation, especially -xylene (PX), is of paramount significance but still remains greatly challenging due to the low efficiency and poor selectivity. The present work utilized a composite catalyst based on ZnZrO with a modified H-ZSM-5 exhibiting nano-prism stacking to realize the selective synthesis of PX. Methoxy species generated from CO-derived formate produced as an intermediate over the ZnZrO were readily incorporated into the xylene products for effective alkylation, contributed to an enhanced aromatics-based cycle that provided a selectivity for xylenes among all C hydrocarbons of 91.1 %. The lengthened straight channels in the H-ZSM-5 along the -axis, derived from the crystal stacking pattern, increased differences in the diffusion properties of the xylene isomers, and thereby steering the movement of molecules toward a product shape-selective pathway, leading to 90.1 % selectivity for PX among all xylenes, and provided exceptional CO utilization efficiency of ∼60 %.
{"title":"Regulating anisotropic diffusion in zeolite for reinforced para-xylene synthesis via CO2 hydrogenation in the presence of toluene","authors":"Xin Shang, Jingfeng Han, Qiao Han, Guangjin Hou, Anmin Zheng, Xiaofeng Yang, Zhiqiang Liu, Guodong Liu, Xiong Su, Yanqiang Huang, Tao Zhang","doi":"10.1016/j.apcatb.2024.124523","DOIUrl":"https://doi.org/10.1016/j.apcatb.2024.124523","url":null,"abstract":"The synthesis of valuable aromatics via CO transformation, especially -xylene (PX), is of paramount significance but still remains greatly challenging due to the low efficiency and poor selectivity. The present work utilized a composite catalyst based on ZnZrO with a modified H-ZSM-5 exhibiting nano-prism stacking to realize the selective synthesis of PX. Methoxy species generated from CO-derived formate produced as an intermediate over the ZnZrO were readily incorporated into the xylene products for effective alkylation, contributed to an enhanced aromatics-based cycle that provided a selectivity for xylenes among all C hydrocarbons of 91.1 %. The lengthened straight channels in the H-ZSM-5 along the -axis, derived from the crystal stacking pattern, increased differences in the diffusion properties of the xylene isomers, and thereby steering the movement of molecules toward a product shape-selective pathway, leading to 90.1 % selectivity for PX among all xylenes, and provided exceptional CO utilization efficiency of ∼60 %.","PeriodicalId":516528,"journal":{"name":"Applied Catalysis B: Environment and Energy","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2024-08-22","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142205138","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2024-08-18DOI: 10.1016/j.apcatb.2024.124512
Youmei Kong, Wei Yang, Jingjing Bao, Licheng Sun, Yang Qiu, Yu Chen, Qiang Zhao, Min Du, Zhengyu Mo
Engineering a robust non-platinum electrode toward hydrogen evolution reaction (HER) is important for water electrolysis. Here we develop a nanotip-structured electrode through a solution phase etching procedure. Based on the experimental and finite element simulation, the results show that the nanotip-structured design of electrodes cannot only lower the adhesion force of bubbles, but also induce a local-concentrated electric field that can promote the formation of Marangoni effect, and K concentrated and local acid-like microenvironment, consequently facilitating the detachment of bubbles and the HER kinetics. The electrochemical measurements and density function theory (DFT) calculation indicate that the constructed electrode exhibits a low H* binding energy and an outstanding HER performance that outperforms the commercial Pt/C in pH-universal medium. Overall, this work provides a feasible strategy for electrode design with a pH-universal feasibility by precisely constructing electrode interfaces.
设计一种坚固耐用的非铂电极以实现氢进化反应（HER）对于电解水非常重要。在这里，我们通过溶液相蚀刻程序开发了一种纳米尖端结构电极。基于实验和有限元模拟的结果表明，纳米尖端结构的电极设计不仅能降低气泡的粘附力，还能诱导局部集中的电场，促进马兰戈尼效应的形成，以及 K 浓度和局部酸样微环境的形成，从而促进气泡的脱落和 HER 动力学的产生。电化学测量和密度函数理论（DFT）计算表明，所构建的电极具有较低的 H* 结合能和出色的 HER 性能，在 pH 值通用介质中优于商用 Pt/C。总之，这项研究通过精确构建电极界面，为具有 pH 通用性的电极设计提供了一种可行的策略。
{"title":"Tip-intensified engineering of interfacial microenvironment toward pH-universal hydrogen evolution reaction","authors":"Youmei Kong, Wei Yang, Jingjing Bao, Licheng Sun, Yang Qiu, Yu Chen, Qiang Zhao, Min Du, Zhengyu Mo","doi":"10.1016/j.apcatb.2024.124512","DOIUrl":"https://doi.org/10.1016/j.apcatb.2024.124512","url":null,"abstract":"Engineering a robust non-platinum electrode toward hydrogen evolution reaction (HER) is important for water electrolysis. Here we develop a nanotip-structured electrode through a solution phase etching procedure. Based on the experimental and finite element simulation, the results show that the nanotip-structured design of electrodes cannot only lower the adhesion force of bubbles, but also induce a local-concentrated electric field that can promote the formation of Marangoni effect, and K concentrated and local acid-like microenvironment, consequently facilitating the detachment of bubbles and the HER kinetics. The electrochemical measurements and density function theory (DFT) calculation indicate that the constructed electrode exhibits a low H* binding energy and an outstanding HER performance that outperforms the commercial Pt/C in pH-universal medium. Overall, this work provides a feasible strategy for electrode design with a pH-universal feasibility by precisely constructing electrode interfaces.","PeriodicalId":516528,"journal":{"name":"Applied Catalysis B: Environment and Energy","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2024-08-18","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142205139","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
The nitrogen fertilizer industry, particularly urea production, notably contributes to greenhouse gas emissions and energy consumption. Urea synthesis via solar energy encounters several challenges. Specifically, solar urea synthesis methods often exhibit low efficiency and yield, primarily stemming from inefficient energy conversion processes and intricate reaction pathways. Moreover, the kinetics of the urea synthesis reaction may be sluggish, thereby impacting the overall production rate. Therefore, in this study, we introduce a novel electron-reserve-enhanced CsCuBr/TiO-Ar (CCBT-Ar) structure for the photocatalytic synthesis of urea from CO and nitrate waste. Theoretical calculations and spectroscopic analysis underscore the critical role of oxygen vacancies (O) within the amorphous TiO shell, enhancing reactant adsorption and catalyzing the rate-determining step (*OCONH→*HOCONH). However, the presence of O also results in significant carrier recombination, acting as trapping centers and reducing urea production activity. Importantly, we demonstrate that -grown carbon nanosheets, in conjunction with TiO, function as efficient electron reservoirs, markedly mitigating trapping-induced recombination and facilitating electron redistribution. These reserved electrons can then actively participate in the urea synthesis process. As a result, the electron-reserve-enhanced structure exhibits robust solar urea yield and selectivity, even in challenging wastewater conditions. This work provides a rational and innovative approach to catalyst development in complex solar synthesis, offering promising avenues for the sustainable production of value-added chemicals while concurrently reducing carbon emissions.
氮肥工业，尤其是尿素生产，是温室气体排放和能源消耗的主要来源。利用太阳能合成尿素遇到了一些挑战。具体来说，太阳能尿素合成方法通常效率和产量较低，这主要源于能量转换过程效率低下和反应途径错综复杂。此外，尿素合成反应的动力学过程可能比较缓慢，从而影响整体生产率。因此，在本研究中，我们引入了一种新型的电子储备增强型 CsCuBr/TiO-Ar （CCBT-Ar）结构，用于从 CO 和硝酸盐废料中光催化合成尿素。理论计算和光谱分析强调了氧空位（O）在无定形氧化钛外壳中的关键作用，它能增强反应物的吸附力并催化速率决定步骤（*OCONH→*HOCONH）。然而，O 的存在也会导致大量载流子重组，成为捕集中心，降低尿素生产活性。重要的是，我们证明了-生长的碳纳米片与 TiO 结合可作为高效的电子贮存器，显著减轻捕获引起的重组，促进电子的再分配。这些储备电子可以积极参与尿素合成过程。因此，即使在具有挑战性的废水条件下，电子储备增强型结构也能表现出强大的太阳能尿素产率和选择性。这项工作为复杂太阳能合成中催化剂的开发提供了一种合理而创新的方法，为可持续生产高附加值化学品并同时减少碳排放提供了前景广阔的途径。
{"title":"Enhanced solar urea synthesis from CO2 and nitrate waste via oxygen vacancy mediated-TiOx support lead-free perovskite","authors":"Haoyue Sun, Zhisheng Lin, Rui Tang, Yuhang Liang, Sibei Zou, Xingmo Zhang, Kaijuan Chen, Rongkun Zheng, Jun Huang","doi":"10.1016/j.apcatb.2024.124511","DOIUrl":"https://doi.org/10.1016/j.apcatb.2024.124511","url":null,"abstract":"The nitrogen fertilizer industry, particularly urea production, notably contributes to greenhouse gas emissions and energy consumption. Urea synthesis via solar energy encounters several challenges. Specifically, solar urea synthesis methods often exhibit low efficiency and yield, primarily stemming from inefficient energy conversion processes and intricate reaction pathways. Moreover, the kinetics of the urea synthesis reaction may be sluggish, thereby impacting the overall production rate. Therefore, in this study, we introduce a novel electron-reserve-enhanced CsCuBr/TiO-Ar (CCBT-Ar) structure for the photocatalytic synthesis of urea from CO and nitrate waste. Theoretical calculations and spectroscopic analysis underscore the critical role of oxygen vacancies (O) within the amorphous TiO shell, enhancing reactant adsorption and catalyzing the rate-determining step (*OCONH→*HOCONH). However, the presence of O also results in significant carrier recombination, acting as trapping centers and reducing urea production activity. Importantly, we demonstrate that -grown carbon nanosheets, in conjunction with TiO, function as efficient electron reservoirs, markedly mitigating trapping-induced recombination and facilitating electron redistribution. These reserved electrons can then actively participate in the urea synthesis process. As a result, the electron-reserve-enhanced structure exhibits robust solar urea yield and selectivity, even in challenging wastewater conditions. This work provides a rational and innovative approach to catalyst development in complex solar synthesis, offering promising avenues for the sustainable production of value-added chemicals while concurrently reducing carbon emissions.","PeriodicalId":516528,"journal":{"name":"Applied Catalysis B: Environment and Energy","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2024-08-17","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142205167","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2024-08-17DOI: 10.1016/j.apcatb.2024.124515
Keivan Rahimi, Aditya Rawal, Yi Fen Zhu, Judy N. Hart, Emma C. Lovell, Jason Scott
Defect engineering in metal oxides is an effective approach for improving advanced oxidation processes. Herein, we report that regulating the defect types present on SnO enables deconvolution of their distinct effects on organic oxidation. Nitrogen annealing created E′ center and non-bridging oxygen hole center (NBOHC) defects, while optimum hydrogenation introduced oxygen vacancies, significantly enhancing catalytic oxidation performance. Based on spectroscopic analysis, extended hydrogenation times passivated NBOHCs and formed new types of defects, such as electrons trapped in oxygen vacancies, which are less catalytically active in comparison with NBOHCs. DFT indicated that oxygen vacancies lower the energy barrier for oxygen activation as well as activation of the C-H bonds in formic acid, corroborating the experimental results of enhanced catalytic activity in samples with optimized defect concentrations. The current work advances understanding of the roles different defects play in enhancing organic oxidation in the ongoing search for efficient materials for oxidation reactions.
{"title":"Defect engineering in SnO2 catalysts for the organic oxidation reaction","authors":"Keivan Rahimi, Aditya Rawal, Yi Fen Zhu, Judy N. Hart, Emma C. Lovell, Jason Scott","doi":"10.1016/j.apcatb.2024.124515","DOIUrl":"https://doi.org/10.1016/j.apcatb.2024.124515","url":null,"abstract":"Defect engineering in metal oxides is an effective approach for improving advanced oxidation processes. Herein, we report that regulating the defect types present on SnO enables deconvolution of their distinct effects on organic oxidation. Nitrogen annealing created E′ center and non-bridging oxygen hole center (NBOHC) defects, while optimum hydrogenation introduced oxygen vacancies, significantly enhancing catalytic oxidation performance. Based on spectroscopic analysis, extended hydrogenation times passivated NBOHCs and formed new types of defects, such as electrons trapped in oxygen vacancies, which are less catalytically active in comparison with NBOHCs. DFT indicated that oxygen vacancies lower the energy barrier for oxygen activation as well as activation of the C-H bonds in formic acid, corroborating the experimental results of enhanced catalytic activity in samples with optimized defect concentrations. The current work advances understanding of the roles different defects play in enhancing organic oxidation in the ongoing search for efficient materials for oxidation reactions.","PeriodicalId":516528,"journal":{"name":"Applied Catalysis B: Environment and Energy","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2024-08-17","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142226226","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2024-08-17DOI: 10.1016/j.apcatb.2024.124513
Yongwoo Kim, Jieun Lee, Abiram Krishnan, Jing Luo, Xue Chen, Faisal M. Alamgir, David W. Flaherty
Cobalt-exchanged ZSM-5 catalyzes the ammoxidation of ethane (2 CH + 3 O + 2 NH → 2 CHCN + 6 HO), yet the active form of cobalt, the role of the Brønsted acidic zeolite, and the reaction pathways remain elusive. Comparisons of rates and selectivities of reactions at distinctive cobalt sites (Co at Al pair sites (CoZ), CoO, cobalt phyllosilicate, and cobalt aluminate) suggest sites that form from CoZ provide the greatest rates and selectivities for CHCN and CH formation. Significantly, we revealed a large fraction of CHCN appears to form directly through a trimolecular reaction at cobalt ions without desorption of intermediates. In parallel, a more conventional sequential pathway dehydrogenates CH, aminates CH, and oxidatively dehydrogenates CHNH to produce CHCN. Combined rate measurements with temperature programmed reactions and infrared spectra demonstrate that O-derived intermediates at cobalt ions initiate both reaction sequences by abstracting H-atom from CH.
{"title":"Formation of acetonitrile and ethylene from activation of ethane over cobalt-exchanged aluminosilicates: Active sites and reaction pathways","authors":"Yongwoo Kim, Jieun Lee, Abiram Krishnan, Jing Luo, Xue Chen, Faisal M. Alamgir, David W. Flaherty","doi":"10.1016/j.apcatb.2024.124513","DOIUrl":"https://doi.org/10.1016/j.apcatb.2024.124513","url":null,"abstract":"Cobalt-exchanged ZSM-5 catalyzes the ammoxidation of ethane (2 CH + 3 O + 2 NH → 2 CHCN + 6 HO), yet the active form of cobalt, the role of the Brønsted acidic zeolite, and the reaction pathways remain elusive. Comparisons of rates and selectivities of reactions at distinctive cobalt sites (Co at Al pair sites (CoZ), CoO, cobalt phyllosilicate, and cobalt aluminate) suggest sites that form from CoZ provide the greatest rates and selectivities for CHCN and CH formation. Significantly, we revealed a large fraction of CHCN appears to form directly through a trimolecular reaction at cobalt ions without desorption of intermediates. In parallel, a more conventional sequential pathway dehydrogenates CH, aminates CH, and oxidatively dehydrogenates CHNH to produce CHCN. Combined rate measurements with temperature programmed reactions and infrared spectra demonstrate that O-derived intermediates at cobalt ions initiate both reaction sequences by abstracting H-atom from CH.","PeriodicalId":516528,"journal":{"name":"Applied Catalysis B: Environment and Energy","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2024-08-17","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142205164","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Metal ion cocatalysts have huge prospect for photocatalytic CO reduction coupled with organic decomposition because of their cost effectiveness and abundant active sites. Herein, we exploit a defect−group oriented tactic to induce dual−structured Co sites on BiOCl with rich surface hydroxyls (OHs) and oxygen vacancies (OVs) (labeled as BiOCl−OH), in which the surface OHs and OVs acted as anchoring points to anchor Co ions. Density functional theory calculations manifested that surface OHs anchored Co ions via hydrogen bonding to produce tight OH−Co sites, meanwhile, surface OVs with unsaturated metal sites and unpaired electrons captured Co ions through chemical bonding to form close−knit OV−Co site. The as−generated OV−Co and OH−Co site served as reductive and oxidative cocatalyst for CO reduction and tetracycline oxidation, respectively, thereby achieving high−efficiency redox activity. This work provided a novel strategy to devise progressive dual functional metal ions cocatalysts for high−efficiency CO reduction and organic pollutants oxidation.
金属离子茧催化剂因其成本效益和丰富的活性位点，在光催化一氧化碳还原和有机物分解方面具有广阔的前景。在此，我们利用缺陷群导向策略，在具有丰富表面羟基（OH）和氧空位（OV）的 BiOCl 上诱导出双重结构的 Co 位点（标记为 BiOCl-OH），其中表面羟基和 OV 可作为锚点锚定 Co 离子。密度泛函理论计算表明，表面 OH 通过氢键锚定 Co 离子，产生紧密的 OH-Co 位点；而表面 OV 具有不饱和金属位点和未配对电子，通过化学键捕获 Co 离子，形成紧密的 OV-Co 位点。生成的 OV-Co 和 OH-Co 位点可分别作为还原和氧化催化剂，用于 CO 还原和四环素氧化，从而实现高效的氧化还原活性。这项工作为设计用于高效 CO 还原和有机污染物氧化的渐进式双功能金属离子协同催化剂提供了一种新的策略。
{"title":"Dual structure cobalt sites on surface hydroxyl and oxygen vacancy of BiOCl for cooperative CO2 reduction and tetracycline oxidation","authors":"Haoyu Sun, Haili Lin, Xuemei Jia, Xinyue Li, Shuang Li, Xin Jin, Qianlong Wang, Shifu Chen, Jing Cao","doi":"10.1016/j.apcatb.2024.124514","DOIUrl":"https://doi.org/10.1016/j.apcatb.2024.124514","url":null,"abstract":"Metal ion cocatalysts have huge prospect for photocatalytic CO reduction coupled with organic decomposition because of their cost effectiveness and abundant active sites. Herein, we exploit a defect−group oriented tactic to induce dual−structured Co sites on BiOCl with rich surface hydroxyls (OHs) and oxygen vacancies (OVs) (labeled as BiOCl−OH), in which the surface OHs and OVs acted as anchoring points to anchor Co ions. Density functional theory calculations manifested that surface OHs anchored Co ions via hydrogen bonding to produce tight OH−Co sites, meanwhile, surface OVs with unsaturated metal sites and unpaired electrons captured Co ions through chemical bonding to form close−knit OV−Co site. The as−generated OV−Co and OH−Co site served as reductive and oxidative cocatalyst for CO reduction and tetracycline oxidation, respectively, thereby achieving high−efficiency redox activity. This work provided a novel strategy to devise progressive dual functional metal ions cocatalysts for high−efficiency CO reduction and organic pollutants oxidation.","PeriodicalId":516528,"journal":{"name":"Applied Catalysis B: Environment and Energy","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2024-08-17","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142205140","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2024-08-15DOI: 10.1016/j.apcatb.2024.124509
Xiaoyu Liu, Xiuan Xi, Yuanfeng Liao, Lingui Huang, Jianwen Liu, Hao Chen, Yan Yi, Jun Long, Jiujun Zhang, Xian-Zhu Fu, Jing-Li Luo
Solid oxide fuel cells (SOFCs) are one of the most efficient energy conversion devices. However, the sluggish oxygen reduction reaction (ORR) kinetics at low temperatures significantly challenge the performance and commercialization of SOFCs. Introducing negative expansion coefficient materials has been recognized as an effective approach to enhancing the ORR catalytic properties, but a clear understanding of this enhanced electrochemical performance is still lacking. In this work, the composite cathode of PrBaSrCoFeO (PBSCF) with different amounts of negative-thermal-expansion material SmZnMnO (SZM) is prepared, and in-depth analysis the effect of SZM on the catalytic activity of cathodic ORR is systematically investigated. Simultaneously, the mechanistic studies verify that the enhanced ORR activity might be attributed to the constructed compression strain during sintering, which significantly improves the adsorption, dissociation, and oxygen ion exchange process of the PBSCF cathode.
{"title":"Deciphering the enhanced oxygen reduction reaction activity of PrBa0.5Sr0.5Co1.5Fe0.5O5+δ via constructing negative thermal expansion offset for high-performance solid oxide fuel cell","authors":"Xiaoyu Liu, Xiuan Xi, Yuanfeng Liao, Lingui Huang, Jianwen Liu, Hao Chen, Yan Yi, Jun Long, Jiujun Zhang, Xian-Zhu Fu, Jing-Li Luo","doi":"10.1016/j.apcatb.2024.124509","DOIUrl":"https://doi.org/10.1016/j.apcatb.2024.124509","url":null,"abstract":"Solid oxide fuel cells (SOFCs) are one of the most efficient energy conversion devices. However, the sluggish oxygen reduction reaction (ORR) kinetics at low temperatures significantly challenge the performance and commercialization of SOFCs. Introducing negative expansion coefficient materials has been recognized as an effective approach to enhancing the ORR catalytic properties, but a clear understanding of this enhanced electrochemical performance is still lacking. In this work, the composite cathode of PrBaSrCoFeO (PBSCF) with different amounts of negative-thermal-expansion material SmZnMnO (SZM) is prepared, and in-depth analysis the effect of SZM on the catalytic activity of cathodic ORR is systematically investigated. Simultaneously, the mechanistic studies verify that the enhanced ORR activity might be attributed to the constructed compression strain during sintering, which significantly improves the adsorption, dissociation, and oxygen ion exchange process of the PBSCF cathode.","PeriodicalId":516528,"journal":{"name":"Applied Catalysis B: Environment and Energy","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2024-08-15","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142205166","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
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