APPLIED SURFACE SCIENCE
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2019
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IF 5.155
Haitao Li,Qiang Gao,Guanshuai Wang,Bo Han,Kaisheng Xia,Chenghang Zhou
Developing high-performance heterogeneous Fenton-like catalyst and understanding its intrinsic catalytic properties are of fundamental and practical significance. In this work, a mesoporous Mn(II)-doped CeO 2 (MCO) with monodisperse spherical morphology and large surface area (141.8 m 2 g −1 ) was fabricated through a simple hydrothermal–calcination process, and further utilized as the heterogeneous catalyst for oxidative degradation of organic pollutants in the presence of H 2 O 2 . The density functional theory (DFT) simulations were carried out to study the H 2 O 2 decomposition process on the MCO surface. It was revealed that the Mn(II) doping in the CeO 2 could significantly promote the complex of the surface Ce sites and H 2 O 2 molecules. More importantly, the manganese dopants could serve as electron reservoirs, capable of reversibly donating and accepting electrons, which facilitated the electron transfer between Ce and H 2 O 2 . Owing to the electron reservoir properties of manganese, this MCO showed significantly enhanced catalytic efficiency in comparison to pure CeO 2 . Moreover, the catalytic activity of MCO almost kept unchanged after reuse several times, demonstrating its long-circulating characteristics. This study provides new and important insights into the electron transfer pathway involved in the heterogeneous Fenton-like process.
研究领域:
材料科学
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环境科学
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催化化学
✓ 已验证
产品关联
DOI
高影响因子
Cell Reports Physical Science
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2024
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IF 7.9
Lang Pei,Zhenggang Luo,Jiasong Zhong,Xusheng Wang,Peng Zhou,Shicheng Yan,Zhigang Zou
A persistent challenge in operating S-scheme photocatalysts involves maintaining complete neutralization of low-energy electrons and holes between reducing and oxidizing photocatalysts. To address this, we propose a charge replenishment-assisted S-scheme mechanism that combines a compatible host catalyst with a luminescence phosphor semiconductor capable of long-term storage of photogenerated electrons. Stored electrons can replenish the host photocatalyst, depleting the low-oxidizing holes, thus prolonging the charge-separated state. The concept is demonstrated in a core-shell-structured SrGa 2 O 4 :Cu 2+ /g-C 3 N 4 (SGO/CN) photocatalyst, where stored electrons with a lifetime of up to several hours can continuously consume holes in the CN. The well-defined core-shell structure, abundant interfacial Sr-N bonds, and staggered band alignment between SGO and CN are crucial for this S-scheme interfacial charge transfer, which contributes to the enhanced CO 2 -to-CO transformation activity and selectivity. This S-scheme heterojunction, incorporating a charge-storing material as an excess electron reservoir, offers a promising template for designing efficient photocatalytic systems.
研究领域:
材料科学
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环境科学
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化学工程
✓ 已验证
产品关联
DOI
高影响因子
JOURNAL OF CATALYSIS
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2024
·
IF 6.5
Hao Yan,Mingyue Zhao,Yueqiang Cao,Xin Zhou,Yibin Liu,Xiaobo Chen,Xiang Feng,Xuezhi Duan,Francisco Zaera,Xinggui Zhou,Chaohe Yang
In-depth understanding and precise tuning of the crystal facet-dependent catalytic properties of supported catalysts are critical for polyol oxidation. Herein, we report a crystal-facet-dependent study of Au-ZnO interfaces for the selective promotion of the oxidation of various polyols and alcohols (glycerol, 1,2-propanediol, 1,2-butanediol, and isopropanol) at the secondary hydroxyl position to produce the corresponding ketones. Three facets of the zinc oxide support, ZnO(1 0 1), ZnO(1 0 0) and ZnO(0 0 1), associated with nanoparticles of various morphologies (spherical (S), rod (R) and disk (D), respectively), were found to induce different electronic local environments and surface oxygen vacancy contents at the Au-ZnO interface. In particular, the ZnO(0 0 1) facet dominating in the Au/ZnO-D nanoparticles can store more electrons from Au, and such electron sink effect, together with the generation of oxygen vacancies (Zn-O v ), synergistically enhances the adsorption of O 2 and polyols at the secondary hydroxyl position. Moreover, it was determined that the as-formed Au δ+ -OH* site resulting from O 2 activation can efficiently extract the hydrogen of the C-H bond of the key RCHO*CH 2 OH intermediate on the Zn-O v site of ZnO(0 0 1) surfaces. Consequently, the Au/ZnO-D catalyst exhibits unprecedented catalytic activity (turnover frequency >500 h −1 ) and ketone selectivity (>80 %) for glycerol oxidation.
研究领域:
催化化学
·
材料科学
✓ 已验证
产品关联
DOI
高影响因子
PHYSICA E-LOW-DIMENSIONAL SYSTEMS & NANOSTRUCTURES
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2012
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IF 1.532
Long Zhang,Lianhuan Du,Xiang Cai,Xiang Yu,Dongdong Zhang,Longcheng Liang,Peihua Yang,Xiaobo Xing,Wenjie Mai,Shaozao Tan,Yu Gu,Jinhui Song
This work aims to investigate the underlying mechanism in the great enhancement of photocatalytic activity when involving graphene. With the introduction of reduced Graphene Oxide (rGO) to ZnO nanoparticles (ZnONPs) by a simple mechanical mixing method, ZnO nanoparticles–reduced Graphene Oxide hybrids (ZnO–rGO) perform significantly better than pure ZnONPs in the degradation of methyl blue (MB) under UV light condition. However, our experiments demonstrated if allowing the MB non-covalently attached on rGO first, the photodegradation of ZnONPs on MB is actually interfered and slowed by the presence of rGO. Combined with these two facts, we concluded that rather than directly participating in the photodegradation of dyes, the rGO in ZnO–rGO hybrids preferentially accepts the photo-generated electrons as an electron reservoir, significantly reduces the chances of the recombination, and effectively prolongs the lifetime of holes in ZnONPs, therefore greatly enhancing the efficiency of hole-induced decomposition of dyes. The photodegradation process induced by ZnO–rGO photocatalyst still mainly occurs on the surface of ZnONPs instead of rGO. Our findings help to understand the role of rGO in improved photocatalytic property in ZnO–rGO system and provide new strategies for developing novel photocatalysts.
研究领域:
材料科学
·
环境科学
✓ 已验证
DOI
高影响因子
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