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S型CeO_(2)/Bi_(2)MoO_(6)微球异质结的理性设计及其高效光催化CO_(2)还原
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作者 许修涛 邵春风 +2 位作者 张金锋 王中辽 代凯 《物理化学学报》 SCIE CAS CSCD 北大核心 2024年第10期39-42,共4页
人工半导体光催化CO_(2)转化被广泛认为是模拟自然碳循环的最有前途的策略之一。其中,Bi_(2)MoO_(6)具有光催化CO_(2)转化的潜力。然而,由于其光生电荷载体的快速复合,其催化性能仍然不足。因此,改善Bi_(2)MoO_(6)的催化效率是一个紧迫... 人工半导体光催化CO_(2)转化被广泛认为是模拟自然碳循环的最有前途的策略之一。其中,Bi_(2)MoO_(6)具有光催化CO_(2)转化的潜力。然而,由于其光生电荷载体的快速复合,其催化性能仍然不足。因此,改善Bi_(2)MoO_(6)的催化效率是一个紧迫的问题。在这项研究中,我们通过水热法合成了Bi_(2)MoO_(6)纳米片,并在其表面同时生长了CeO_(2)纳米颗粒,形成了Ce^(3+)/Ce^(4+)离子桥接修饰的S型异质结。时间分辨光致发光光谱和光电化学测试揭示了这种异质结的增强电荷分离效应。此外,原位X射线光电子能谱分析和理论计算进一步证实,光生电子转移路径遵循S型机制,从氧化型半导体Bi_(2)MoO_(6)的导带转移到还原型半导体CeO_(2)的价带。实验结果表明,CeO_(2)/Bi_(2)MoO_(6)、Bi_(2)MoO_(6)和CeO_(2)的光催化CO_(2)还原为CO的效率分别为65.3、14.8和1.2μmol·g^(-1)·h^(-1)。与纯Bi_(2)MoO_(6)相比,CeO_(2)/Bi_(2)MoO_(6)复合催化剂将CO_(2)光催化还原为CO的催化效率提高了3.12倍。这项工作为设计和构建新型S型异质结光催化剂提供了独特的见解。 展开更多
关键词 光催化CO_(2)转化 CeO_(2) Bi_(2)MoO_(6) S型异质结 电荷转移
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双聚合物Cd_(3)(C_(3)N_(3)S_(3))_(2)/Zn_(3)(C_(3)N_(3)S_(3))_(2)S型异质结增强光催化产氢性能
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作者 杨婷婷 汪静 +2 位作者 王中辽 张金锋 代凯 《Chinese Journal of Catalysis》 SCIE CAS CSCD 2024年第3期157-167,共11页
利用光催化剂将太阳能转化为化学能,以应对当今社会所面临的环境污染和能源挑战,是一种极具发展潜力的策略.因此,研发高效光催化剂成为当务之急.在众多光催化剂中,金属硫化物受到广泛关注.其中,CdS因其出色的产氢性能而被视为一种具有... 利用光催化剂将太阳能转化为化学能,以应对当今社会所面临的环境污染和能源挑战,是一种极具发展潜力的策略.因此,研发高效光催化剂成为当务之急.在众多光催化剂中,金属硫化物受到广泛关注.其中,CdS因其出色的产氢性能而被视为一种具有前景的光催化剂,并备受关注.然而,CdS易发生光腐蚀,导致S2‒阴离子容易被产生的空穴氧化,从而影响了其光化学稳定性,限制了其应用.为解决上述问题,本课题组尝试用(C_(3)N_(3)S_(3))_(3)‒代替S2‒合成了不易受光腐蚀且相对稳定的聚合物Cd_(3)(C_(3)N_(3)S_(3))_(2)(CdTMT),CdTMT是一种对可见光有良好响应的大分子配位聚合物,在光催化制氢方面表现出较好的催化性能.本文以八面体CdTMT为基底,通过生长棒状Zn_(3)(C_(3)N_(3)S_(3))_(2)(ZnTMT),利用简便的一步原位水热法制备了不同比例的CdTMT/ZnTMT S型异质结光催化剂.通过X射线衍射、扫描电镜以及透射电镜对样品的晶体结构、微观形貌以及组成元素进行了表征,并利用X射线光电子能谱、开尔文探针力显微镜和电子顺磁共振等技术对复合材料的电子传输行为进行了详细分析.结果表明,在黑暗状态下,电子由CdTMT转移到ZnTMT,当光照时电子由ZnTMT转移到CdTMT,证实了CdTMT/ZnTMT S型异质结的成功构建.同时,拉曼光谱证明了三嗪环的存在.此外,考察了纯样品和复合材料的光催化析氢性能.结果表明,在光照下S型CdTMT/ZnTMT异质结的光催化析氢效率相较于单一催化剂ZnTMT与CdTMT有显著提升,最高达到45.24 mmol·g^(‒1)·h^(‒1),分别是ZnTMT和CdTMT的215.43倍和1.76倍.CdTMT/ZnTMT S型异质结的内建电场、能带弯曲和库仑力以及π共轭轨道之间存在协同作用,不仅保留了CdTMT导带上电子与ZnTMT价带上空穴的强氧化还原能力,而且通过重新配置氧化还原活性较低的光生电子和空穴,实现了更高的电子-空穴分离效率,从而增强了复合材料的光催化活性.上述结果与表征和密度泛函理论计算结果一致.鉴于聚合物体系在自然环境中的无序性,研究聚合物的电子传递机制仍具有一定的挑战性.本文通过成功构建双聚合物S型异质结,在显著优化光催化剂性能的同时,也为设计聚合物电子转移机制和优化聚合物光催化剂性能提供了新思路. 展开更多
关键词 S型异质结 光催化析氢 电荷转移 ZnTMT CdTMT
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光激发电荷在光催化氧化还原反应中的全利用 被引量:7
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作者 王中辽 汪静 +1 位作者 张金锋 代凯 《物理化学学报》 SCIE CAS CSCD 北大核心 2023年第6期4-25,共22页
光催化转化CO_(2)为碳氢燃料,分解水产氢,选择性有机合成,还原N_(2)为NH_(3),降解毒害的有机污染物等对解决能源环境问题有重要意义。早在1972年,研究者利用TiO_(2)通过光催化实现了全面分解水产氢和产氧。由于低的可见光利用率,严重的... 光催化转化CO_(2)为碳氢燃料,分解水产氢,选择性有机合成,还原N_(2)为NH_(3),降解毒害的有机污染物等对解决能源环境问题有重要意义。早在1972年,研究者利用TiO_(2)通过光催化实现了全面分解水产氢和产氧。由于低的可见光利用率,严重的载流子复合和过高的水氧化能垒导致光催化全面水分解的效率极低。由于氢相对于氧更具有经济价值,因此牺牲剂辅助的光催化产氢被大量研究。由于牺牲剂可以快速的消耗光生空穴,有效降低了氧化端的能垒,光催化产氢的效率相比于光催化水分解的效率提高了3–4个量级。然而,牺牲剂的使用不仅导致了光生空穴的浪费,成本的提高,还导致了潜在的环境问题。近些年,研究者通过将光催化还原反应和光催化氧化反应结合在一起实现了电子空穴的全面利用,并改进了氧化和还原的效率。同时,电子空穴的全面利用也有效的促进了电荷的分离并提高了催化剂的稳定性。然而,由于全面氧化还原的设计难度大,反应过程复杂,因此光催化全面氧化还原的机理尚不够明确,仍然需要大量的探索。在这篇综述中,首先从光捕获、光激发电荷分离、氧化还原反应的热力学和动力学过程等角度讨论了光催化的基本原理。然后根据不同的光催化氧化反应和光催化还原反应的耦合,比如光催化整体水分解、光催化产H_(2)与有机氧化耦合、光催化CO_(2)还原与有机氧化耦合、光催化产H_(2)O_(2)与有机氧化耦合、光催化N_(2)还原与N_(2)氧化耦合、光催化有机还原与有机氧化耦合等光催化全面氧化还原反应进行了系统分类。随后,从光催化材料的设计、反应条件、反应物和产物的多样性等方面详细考虑了光催化氧化还原反应的设计要点。此外,通过功函数、电子密度差、Bader电荷、吸附自由能的变化,讨论了密度泛函理论(DFT)计算在揭示光激发电荷转移、中间体转变过程中的速率决定步骤和氧化还原反应势垒方面的重要作用。然后,结合典型案例,尽可能通过原位表征和DFT计算,详细分析了各种光催化氧化还原反应的活性和机理。最后,从构建S型异质结光催化剂、合理负载助催化剂、设计光催化剂形貌、开发新型光催化剂、合理选择氧化半反应和还原半反应耦合、原位表征和DFT计算的结合等角度对光催化全面氧化还原反应的应用进行了总结和展望。该工作为光催化整体氧化还原反应的设计策略和机理洞察提供了参考。 展开更多
关键词 光催化 整体氧化还原反应 太阳能利用 电荷分离 协同效应
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LSPR效应增强碳包覆In_(2)O_(3)/W_(18)O_(49)S型异质结用于高效CO_(2)光还原
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作者 何厚伟 王中辽 +2 位作者 代凯 李素文 张金锋 《Chinese Journal of Catalysis》 SCIE EI CAS CSCD 2023年第5期267-278,共12页
太阳能驱动的光催化CO_(2)还原(PCR)技术可以将CO_(2)转化为增值燃料,被认为是可以解决化石能源的日益减少和环境污染问题的可持续能源转换技术.CO_(2)的光催化还原涉及多种催化剂和反应途径,构建异质结催化剂是提高光催化CO_(2)还原效... 太阳能驱动的光催化CO_(2)还原(PCR)技术可以将CO_(2)转化为增值燃料,被认为是可以解决化石能源的日益减少和环境污染问题的可持续能源转换技术.CO_(2)的光催化还原涉及多种催化剂和反应途径,构建异质结催化剂是提高光催化CO_(2)还原效率的重要策略.然而,异质结催化剂的光吸收范围一直是影响其性能的重要因素.在增强近红外区光吸收的众多材料中,具有局部表面等离子体共振(LSPR)效应的非贵金属等离子体材料是合适的选择.W_(18)O_(49)具有特殊的缺陷结构和LSPR效应,可以产生高能“热电子”并促进载流子转移,进一步优化了W_(18)O_(49)敏化光催化复合材料的设计,在光催化中显示出非凡的潜力和研究价值.本文在源自In-MOF的碳包覆In_(2)O_(3)(C-In_(2)O_(3))纳米棒外表面组装一维高吸光度W_(18)O_(49)纳米线,设计和制备C-In_(2)O_(3)/W_(18)O_(49)分级S型异质结.采用X射线衍射、扫描电镜和透射电镜对样品进行了结构和形貌表征,结果表明,成功制备了C-In_(2)O_(3)/W_(18)O_(49)复合材料.通过X射线光电子能谱和密度泛函理论计算分析了电子流向,验证了S型异质结的机理.使用原位漫反射红外傅里叶变换光谱、气相色谱和同位素标定进一步确定了PCR反应中间体活化过程和反应产物,其中40%C-In_(2)O_(3)/W_(18)O_(49)复合材料的CO产率最高,达到135.82μmol·h^(-1)·g^(-1),分别是纯C-In_(2)O_(3)和W_(18)O_(49)的2.99和2.84倍.采用时间分辨瞬态光致发光光谱测定样品的荧光寿命,结果表明,C-In_(2)O/W_(18)O_(49)复合材料拥有更长的载流子衰变动力学的平均寿命(4.0707 ns),表明复合材料可以更有效地利用可见光进行光催化反应.C-In_(2)O_(3)/W_(18)O_(49)复合材料较好的催化性能主要归因于以下两个方面.(1)碳涂层的高电子电导率促进了C-In_(2)O_(3)和W_(18)O_(49)之间的电荷转移,载流子在非均相界面的均匀分布和高清的转移是光催化活性提高的重要原因;(2)S型异质结中的内部电子转移和注入C-In_(2)O_(3)的LSPR诱导的“热电子”实现了PCR的双路径电子转移,从而使得PCR反应的活性得到了显著提高.综上,本文为开发高效可见光催化剂提供了新思路和实验依据. 展开更多
关键词 光催化CO_(2)还原 S型异质结 局部表面等离子体共振 碳包覆氧化铟 W_(18)O_(49)
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金属硫化物基异质结光催化剂:原理、影响、应用和原位表征
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作者 张海波 王中辽 +1 位作者 张金锋 代凯 《Chinese Journal of Catalysis》 SCIE EI CAS CSCD 2023年第6期42-67,共26页
金属硫化物的窄带隙使其具有吸收可见光和红外光的优势,因此可以用于开发高效的光催化剂.同时,金属硫化物具有出色的电荷分离、较强的光还原能力和低氧化还原能垒.然而,单一金属硫化物通常具有光吸收强度不高和电子-空穴快速复合的问题... 金属硫化物的窄带隙使其具有吸收可见光和红外光的优势,因此可以用于开发高效的光催化剂.同时,金属硫化物具有出色的电荷分离、较强的光还原能力和低氧化还原能垒.然而,单一金属硫化物通常具有光吸收强度不高和电子-空穴快速复合的问题.在仅考虑光吸收范围时,应选择带隙较窄的光催化剂,但其氧化还原能力较低.此外,金属硫化物易发生光腐蚀.近年来,研究发现,在两种及以上光催化剂间构建异质结可以抑制单一催化剂载流子的复合,促使电子与空穴的分离;同时,异质结光催化剂也被证实可以提高光吸收和增加反应活性位点,是解决金属硫化物自身不足的重要措施.本文总结了金属硫化物用于光催化反应的优势和缺陷,讨论了构建异质结对单一金属硫化物的影响.不同的合成方法对于异质结光催化剂的形貌结构及性能具有重要影响,列举了一些金属硫化物异质结合成方法实例,例如水热合成法、离子交换法、静电纺丝法和原位光化学沉积法等.异质结光催化剂的种类可以根据电子转移机理分为肖特基结、typeⅡ型、Z型和S型异质结等.随后,概述了金属硫化物异质结在环境和能源领域的应用,比较了不同类型金属硫化物异质结的光催化活性.充分利用光生电子和空穴分别驱动氧化和还原反应,这不仅提高了光催化效率,而且拓宽了光催化剂的应用.此外,对异质结的电子转移机理进行了深入讨论,以往的表征手段通常只能间接证明异质结可以抑制电子空穴的复合,进而促进光催化活性,并未直接观察到电子转移路径.近年来,原位表征技术的快速发展弥补了异质结的证据不足,通过原位X射线光电子能谱、原位开尔文探针力显微镜和原位电子顺磁共振等表征手段可以观察到电子转移路径,并可利用原位红外监测反应过程中的中间产物和副产物的生成情况,逐步完善了异质结光催化剂机理的探究.本文还展望了金属硫化物异质结构建过程中面临的一些挑战,虽然金属硫化物基异质结光催化剂改善了载流子快速重组的缺点,但其光催化活性仍未达到实现产业化应用的水平.开发出一种具有宽谱带范围可见光吸收、快速电荷分离、大量活性位点、强氧化还原能力和较好稳定性的高性能金属硫化物基异质结光催化剂仍需做大量的工作.未来可以通过调控形貌、元素掺杂、缺陷工程和增加反应活性位点等策略来进一步提高金属硫化物基异质结光催化剂的活性. 展开更多
关键词 光催化 金属硫化物 异质结 电荷分离 应用
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Construction of Z-scheme Ag_3PO_4/Bi_2WO_6 composite with excellent visible-light photodegradation activity for removal of organic contaminants 被引量:17
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作者 zhongliao wang Taiping Hu +2 位作者 Kai Dai Jinfeng Zhang Changhao Liang 《Chinese Journal of Catalysis》 CSCD 北大核心 2017年第12期2021-2029,共9页
Ag3PO4has good potential for use in photocatalytic degradation of organic contaminants.However,the activity and stability of Ag3PO4is hard to sustain because of photocorrosion and the positive potential of the conduct... Ag3PO4has good potential for use in photocatalytic degradation of organic contaminants.However,the activity and stability of Ag3PO4is hard to sustain because of photocorrosion and the positive potential of the conduction band of Ag3PO4.In this study,A composite consisting of Bi2WO6nanosheets and Ag3PO4was developed to curb recombination of charge carriers and enhance the activity and stability of the catalyst.Formation of a Ag3PO4/Bi2WO6composite was confirmed using X‐ray diffraction,energy‐dispersive X‐ray spectroscopy,and X‐ray photoelectron spectroscopy.Photoluminescence spectroscopy provided convincing evidence that compositing Bi2WO6with Ag3PO4effectively reduced photocorrosion of Ag3PO4.The Ag3PO4/Bi2WO6composite gave a high photocatalytic performance in photodegradation of methylene blue.A degradation rate of0.61min?1was achieved;this is1.3and6.0times higher than those achieved using Ag3PO4(0.47min?1)and Bi2WO6(0.10min?1),respectively.Reactive species trapping experiments using the Ag3PO4/Bi2WO6composite showed that holes,?OH,and?O2?all played specific roles in the photodegradation process.The photocatalytic mechanism was investigated and a Z‐scheme was proposed as a plausible mechanism. 展开更多
关键词 Ag3PO4 Bi2WO6 PHOTOCATALYSIS Z‐scheme Degradation Visible light
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S‐Scheme 2D/2D Bi_(2)MoO_(6)/BiOI van der Waals heterojunction for CO_(2) photoreduction 被引量:6
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作者 zhongliao wang Bei Cheng +4 位作者 Liuyang Zhang Jiaguo Yu Youji Li S.Wageh Ahmed A.Al‐Ghamdi 《Chinese Journal of Catalysis》 SCIE EI CAS CSCD 2022年第7期1657-1666,共10页
Reducing CO_(2) to hydrocarbon fuels by solar irradiation provides a feasible channel for mitigating excessive CO_(2) emissions and addressing resource depletion.Nevertheless,severe charge recombi‐nation and the high... Reducing CO_(2) to hydrocarbon fuels by solar irradiation provides a feasible channel for mitigating excessive CO_(2) emissions and addressing resource depletion.Nevertheless,severe charge recombi‐nation and the high energy barrier for CO_(2) photoreduction on the surface of photocatalysts com‐promise the catalytic performance.Herein,a 2D/2D Bi_(2)MoO_(6)/BiOI composite was fabricated to achieve improved CO_(2) photoreduction efficiency.Charge transfer in the composite was facilitated by the van der Waals heterojunction with a large‐area interface.Work function calculation demon‐strated that S‐scheme charge transfer is operative in the composite,and effective charge separation and strong redox capability were revealed by time‐resolved photoluminescence and electron para‐magnetic resonance spectroscopy.Moreover,the intermediates of CO_(2) photoreduction were identi‐fied based on the in situ diffuse reflectance infrared Fourier‐transform spectra.Density functional theory calculations showed that CO_(2) hydrogenation is the rate‐determining step for yielding CH_(4) and CO.Introducing Bi_(2)MoO_(6) into the composite further decreased the energy barrier for CO_(2) photoreduction on BiOI by 0.35 eV.This study verifies the synergistic effect of the S‐scheme heterojunction and van der Waals heterojunction in the 2D/2D composite. 展开更多
关键词 2D/2D S‐scheme heterojunction van der Waals heterojunction CO_(2)photoreduction
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乙基修饰的氮化碳增强光催化CO_(2)转化 被引量:2
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作者 陈冻冻 王中辽 +2 位作者 傅俊伟 张金锋 代凯 《Science China Materials》 SCIE EI CAS CSCD 2024年第2期541-549,共9页
光催化剂的表面官能团对光生载体的转移和反应的活性位点起着关键作用,对光催化转化过程影响很大.因此,合理准确地调控表面基团可以极大地优化光催化性能.本文通过引入给电子能力强的乙基,对氮化碳(g-C_(3)N_(4))未聚合的NH_(2)基团进... 光催化剂的表面官能团对光生载体的转移和反应的活性位点起着关键作用,对光催化转化过程影响很大.因此,合理准确地调控表面基团可以极大地优化光催化性能.本文通过引入给电子能力强的乙基,对氮化碳(g-C_(3)N_(4))未聚合的NH_(2)基团进行优化.通过X射线光电子能谱证实了乙基包埋的成功.时间分辨光谱和密度泛函理论(DFT)计算证实了光生载流子沿有利方向变化.最后,Gibbs自由能表明,乙基改性的氮化碳具有显著降低的CO_(2)转化为*COOH的能垒.其CO_(2)到CO的转化率为47.08μmolg^(-1)h^(-1).本研究为通过优化表面官能团来提高光催化剂性能的研究提供了可靠参考. 展开更多
关键词 photocatalytic CO_(2)reduction ethyl group carbon nitride charge separation
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Review on inorganic-organic S-scheme photocatalysts 被引量:4
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作者 Jing wang zhongliao wang +1 位作者 Kai Dai Jinfeng Zhang 《Journal of Materials Science & Technology》 SCIE EI CAS CSCD 2023年第34期187-218,共32页
The inorganic-organic S-scheme heterojunction photocatalyst demonstrates exceptional light absorption capacity,high photogenerated charge separation efficiency,and remarkable redox ability,while also inheriting divers... The inorganic-organic S-scheme heterojunction photocatalyst demonstrates exceptional light absorption capacity,high photogenerated charge separation efficiency,and remarkable redox ability,while also inheriting diverse advantages of both inorganic and organic semiconductors.This paper provides a comprehensive review of recent advances in photocatalysis in relation to the inorganic-organic S-scheme heterojunction photocatalyst.Firstly,the fundamental aspects and benefits of the S-scheme heterojunction photocatalyst are outlined,followed by a discussion of several synthetic techniques for producing the inorganic-organic S-scheme heterojunction photocatalyst,as well as various advanced characterization methods that can verify the S-scheme heterojunction photocatalyst in both steady-state and transient processes.The impact of the inorganic-organic S-scheme heterojunction photocatalyst is illustrated with examples in fields such as carbon dioxide reduction,water splitting for hydrogen production,hydrogen peroxide synthesis,nitrogen fixation,organic pollutant degradation,organic transformation,and sterilization.Finally,suggestions are presented for designing the inorganic-organic S-scheme heterojunction photocatalyst and enhancing its photocatalytic performance.Undoubtedly,the inorganic-organic Sscheme heterojunction photocatalyst has emerged as a prominent and promising technology in the field of photocatalysis. 展开更多
关键词 PHOTOCATALYSIS S-scheme Inorganic-organic hybrid Application
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A hierarchical Bi-MOF-derived BiOBr/Mn_(0.2)Cd_(0.8)S S-scheme for visible-light-driven photocatalytic CO_(2) reduction 被引量:3
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作者 Jiahui Hua zhongliao wang +3 位作者 Jinfeng Zhang Kai Dai Chunfeng Shao Ke Fan 《Journal of Materials Science & Technology》 SCIE EI CAS CSCD 2023年第25期64-71,共8页
S-scheme heterojunctions have promising applications in photocatalytic CO_(2) reduction due to their unique structure and interfacial interactions,but improving their carrier separation efficiency and CO_(2) adsorptio... S-scheme heterojunctions have promising applications in photocatalytic CO_(2) reduction due to their unique structure and interfacial interactions,but improving their carrier separation efficiency and CO_(2) adsorption capacity remains a challenge.In this work,highly dispersed MOF-BiOBr/Mn_(0.2) Cd_(0.8) S(MOF-BiOBr/MCS)S-scheme heterojunctions with high photocatalytic CO_(2) reduction performance were constructed.The intimate contact between the MCS nano-spheres and the nanosheet-assembled MOF-BiOBr rods,driven by the internal electric field,accelerates the charge transfer along the S-scheme pathway.Moreover,the high specific surface area of MOFs is preserved to provide abundant active sites for reaction/adsorption.The formation of MOF-BiOBr/MCS S-scheme heterojunction is confirmed by theoretical calculations.The optimum MOF-BiOBr/MCS shows excellent activity in CO_(2) reduction,affording a high CO evolution rate of 60.59µmol h^(−1) g^(−1).The present work can inspire the exploration for the construction of effective heterostructure photocatalysts for photoreduction CO_(2). 展开更多
关键词 Mn0.2Cd0.8S Bi-MOF CO_(2)reduction S-scheme heterojunction
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Single-layer crystalline triazine-based organic framework photocatalysts with different linking groups for H_(2)O_(2)production
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作者 Jing wang zhongliao wang +1 位作者 Jinfeng Zhang Kai Dai 《Chinese Journal of Structural Chemistry》 SCIE CAS CSCD 2023年第12期33-42,共10页
Harnessing solar energy for photocatalytic hydrogen peroxide(H_(2)O_(2))synthesis represents a pinnacle of environmentally-sensitive and sustainable methodologies.While single-layer crystalline triazine-based organic ... Harnessing solar energy for photocatalytic hydrogen peroxide(H_(2)O_(2))synthesis represents a pinnacle of environmentally-sensitive and sustainable methodologies.While single-layer crystalline triazine-based organic frameworks(CTFs)are known for their prodigious photocatalytic potential in H_(2)O_(2)generation,ramifications of the connecting group within the triazine ring(TR)on underlying photocatalytic mechanism warrant deeper exploration.In this study,we simulate three distinct CTFs characterized by different TR linkers:CTF-1(benzene group(BG)),CTF-2(horizontally-oriented naphthyl group(NGH)),and CTF-DCN(vertically-oriented naphthyl group(NGV)).These diverse TR linkers profoundly modulate the absorption band edge of CTFs,subsequently dictating the orientation and constitution of the frontier orbitals.Such modulation plays a decisive role in determining the requisite energy for photoexcitation in CTFs,orchestrating the generation and distribution of photo-induced electrons and holes.Remarkably,the NGV linkage imparts CTF-DCN with unparalleled light ab-sorption,superior charge separation efficiency,and the lowest energy barrier for associated reactions.Through this investigation,we illuminate the pivotal influence of TR linkers in sculpting the photocatalytic dynamics of CTFs,providing fresh perspectives for architecting CTFs with amplified photocatalytic prowess in H_(2)O_(2)synthesis. 展开更多
关键词 SINGLE-LAYER CTFs H_(2)O_(2)photoreduction DFT calculation Structural design
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Step-scheme CdS/TiO_(2) nanocomposite hollow microsphere with enhanced photocatalytic CO_(2) reduction activity 被引量:13
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作者 zhongliao wang Yifan Chen +3 位作者 Liuyang Zhang Bei Cheng Jiaguo Yu Jiajie Fan 《Journal of Materials Science & Technology》 SCIE EI CAS CSCD 2020年第21期143-150,共8页
Converting solar energy into chemical energy by artificial photosynthesis is promising in addressing the issues of the greenhouse effect and fossil fuel crisis.Herein,a novel photocatalyst,i.e.CdS/TiO_(2) hollow micro... Converting solar energy into chemical energy by artificial photosynthesis is promising in addressing the issues of the greenhouse effect and fossil fuel crisis.Herein,a novel photocatalyst,i.e.CdS/TiO_(2) hollow microspheres(HS),were dedicatedly designed to boost overall photocatalytic efficiency.TiO_(2) nanoparticles were in-situ decorated on the inside and outside the shell of Cd S HS,ensuring close contact between TiO_(2) and CdS.The CdS/TiO2 HS with abundant mesopores inside of the shell boost the light absorption via multiscattering effect as well as accessible to reactions in all directions.The heterojunction was scrutinized and the charge transfer across it was revealed by in-situ irradiated X-ray photoelectron spectroscopy(ISI-XPS).Ultimately,the charge transfer in this composite was determined to follow stepscheme mechanism,which not only facilitates the separation of charge carriers but also preserves strong redox ability.Benefited from the intimate linkage between Cd S and TiO_(2) and the favorable step-scheme heterojunction,enhanced photocatalytic CO_(2) reduction activity was accomplished.The CH4 yield rate of CdS/TiO_(2) reaches 27.85μmol g^(–1) h^(–1),which is 145.6 and 3.8 times higher than those of pristine CdS and TiO_(2),respectively.This work presents a novel insight into constructing step-scheme photocatalytic system with desirable performance. 展开更多
关键词 Step-scheme heterojunction CDS TiO_(2) Hollow microspheres Photocatalytic CO2 reduction
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S-scheme Porous g-C_(3)N_(4)/Ag_(2)MoO_(4)Heterojunction Composite for CO_(2)Photoreduction 被引量:5
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作者 zhongliao wang Ruilian Liu +1 位作者 Jinfeng Zhang Kai Dai 《Chinese Journal of Structural Chemistry》 SCIE CAS CSCD 2022年第6期15-22,共8页
Utilizing solar energy to achieve artificial photosynthesis of chemical fuel is prevalent in tackling excessive CO_(2)emission and fossil fuel depletion.Grievous charge recombination and weak redox capability aggravat... Utilizing solar energy to achieve artificial photosynthesis of chemical fuel is prevalent in tackling excessive CO_(2)emission and fossil fuel depletion.Grievous charge recombination and weak redox capability aggravate the CO_(2)photoreduction performance.Engineering tailored morphology and constructing matched heterostructure are two significant schemes to ameliorate the CO_(2)photoconversion efficiency of g-C_(3)N_(4)-based composite.Herein,a novel S-scheme ultrathin porous g-C_(3)N_(4)(UPCN)/Ag_(2)MoO_(4)(AMO)composite was designed by in-situ growing tetragonalα-AMO nanoparticles(NPs)(5-30 nm)on UPCN nanosheets(NSs).The S-scheme charge transfer route endows UPCN/AMO with fast charge separation and strong redox capability,demonstrated by X-ray photoelectron spectroscopy(XPS),photoelectrochemical tests,steady-state and time-resolved photoluminescence(PL)spectra,and DFT calculations.The UPCN/AMO composite exhibits elevated CO_(2)photoreduction performance with CO and CH_(4)yield rates of 6.98 and 0.38μmol g^(-1)h^(-1),which are 3.5 and 2.9 folds higher than that of pristine UPCN,respectively.Finally,the CO_(2)photoreduction intermediates are analyzed,and the CO_(2)photoreduction mechanism is discussed.This work provides a reference for various g-C_(3)N_(4)-based composites applied in artificial photosynthesis. 展开更多
关键词 S-scheme g-C_(3)N_(4) Ag_(2)MoO_(4) HETEROJUNCTION CO_(2)photoreduction
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