Catalysts
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2022
·Vol. 12
·期 9
·1043
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IF 4.501
Shuang Tang,Yang-Sen Xu,Wei-De Zhang
Molecular skeleton modification has become a recognized method that can effectively improve the photocatalytic performance of g-C3N4because it not only effectively promotes charge separation, but also tunes the conjugated system of g-C3N4to make it more conducive to photocatalytic reaction. Herein, thiophene-amide embedded g-C3N4(TA-CN-x) was successfully prepared by simple one-step thermal polycondensation using urea as a precursor and ethyl-2-amino-4-phenylthiophene-3-carboxylate (EAPC) as an additive. After embedding with thiophene-amide, the induction and delocalization effects are formed in TA-CN-x, which significantly improves the migration efficiency of photogenerated charge carriers. Meanwhile, the conjugate structure is changed due to structural modification, resulting in significant enhancement of visible light absorption compared to the pure g-C3N4(CN). Specifically, the optimized photocatalytic H2evolution rate of TA-CN-2 reaches 245.4 μmol·h−1, which is 8.4 times that of CN (with Pt nanoparticles as a co-catalyst), and the apparent quantum efficiency (AQY) at 450 nm is 13.6%. This work opens up a new modification process for fully tapping the photocatalytic hydrogen absorption potential of g-C3N4-based materials.Keywords:photocatalysts;g-C3N4;thiophene-amide;embedding;induction effect;delocalization effect;hydrogen evolution
研究领域:
材料科学
·
化学
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产品关联
DOI
高影响因子
Science Advances
·
2020
·Vol. 6
·期 17
·
IF 13.117
Xiaofei Zhang,Haitao Liu,Pengfei An,Yanan Shi,Jianyu Han,Zhongjie Yang,Chang Long,Jun Guo,Shenlong Zhao,Kun Zhao,Huajie Yin,Lirong Zheng,Binhao Zhang,Xiaoping Liu,Lijuan Zhang,Guodong Li,Zhiyong Tang
CO2 cycloaddition with epoxides at low temperature and pressure has been broadly recognized as an ambitious but challenging goal, which requires the catalysts to have precisely controlled Lewis acid sites. Here, we demonstrate that both stereochemical environment and oxidation state of single cobalt active sites in cobalt tetraaminophthalocyanine [CoPc(NH2)4] are finely tuned via molecular engineering with 2,5-di-tert-butyl-1,4-benzoquinone (DTBBQ). Notably, DTBBQ incorporation not only enables formation of 5-nm-thick conjugated microporous polymer (CMP) nanosheets due to the steric hindrance effect of tert-butyl groups but also makes isolated cobalt sites with high oxidation state due to the presence of delocalized electron-withdrawing effect of alkene groups in DTBBQ via conjugated skeleton. Notably, when used as heterogeneous catalysts for CO2 cycloaddition with different epoxides, single cobalt active sites on the ultrathin CMP nanosheets exhibit unprecedentedly high activity and excellent stability under mild reaction conditions.
研究领域:
材料科学
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催化化学
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产品关联
DOI
PubMed
高影响因子
FUEL
·
2023
·
IF 7.4
Mei Luo,Xiangmin Fu,Shuo Geng,Ziwei Li,Min Li
CO 2 electrocatalysis reduction (CO 2 RR) is considered to be one of the most efficient methods to achieve carbon neutralization and realize renewable energy conversion. Unfortunately, at present, CO 2 electrocatalysts confront the challenges of high overpotential, low selectivity, and poor stability. Ag based electrocatalysts are considered to be the most promising catalysts for CO production via CO 2 RR on a large scale, due to their relatively higher catalytic performance and more abundant reserves compared with other noble metals. Whereas, they still suffer from high cost. In this paper, we design bimetallic CuAg/CeO 2 -6 catalysts by the simple impregnation method for CO 2 RR, exhibiting the highest FE CO of 84% at –1.1 V vs. RHE compared with other bimetallic catalysts with different Cu/Ag ratio and monometal catalysts. XPS results demonstrate the electron delocalization effect not only between Cu and Ag bimetals but also among CeO 2 support. This effect results in the electronic structure change and the formation of the highest concentration of oxygen vacancies, promoting the CO 2 adsorption and activation as well as facilitating the formation of COOH* intermediates as evidenced by the in situ ATR-SEIRAS measurements. Additionally, the highest active surface for CO 2 RR and the smallest charge resistance of CuAg/CeO 2 -6 also contributes to its good CO 2 RR performance. This work sheds light on the design of other efficient CO 2 RR catalysts through electronic structure tuning by bimetallic strategy.
研究领域:
电化学
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催化
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材料科学
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可再生能源
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产品关联
DOI
高影响因子
CHEMICAL ENGINEERING JOURNAL
·
2025
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IF 13.2
Wenpeng Cao,Kai Du,Changzhan Li,Pengcheng Liu,Mingming Xie,Fangyan Cui,Chunhao Sun,Mingshan Han,Jinshu Wang,Yuxiang Hu
Rechargeable aluminum batteries (RABs) are promising in the energy storage fields owing to their high theoretical capacity, abundant resources, and high safety. However, the intrinsically high-charge-density of aluminum ions (Al 3+ , 364C mm −3 ), inevitably leads to large lattice strain and low electron transfer efficiency towards conventional cathodes, such as transition metal sulfides, with inferior performance. To overcome the inherent confinement, we first-timely propose the high-entropy sulfides (HESs) as the novel cathodes in RABs, exhibiting robust lattice tolerance and accelerated multi-path electron transfer. Benefiting from the interaction of multiple atoms and inherent long-range disorder in HESs, broadened atomic d-band ( ɛ d ) endows the local “electronic delocalization effect” with a high rate-capacity (above 193.0 mAh g −1 at 5.0 A g −1 ). Moreover, the well-constructed cathode forms a strong lattice strain field, providing one of the best long-term stabilities (0.004 % per cycle capacity decay over 12,000 cycles at a high current density of 5.0 A g −1 ) in RABs. Overall, the newly developed HESs with lattice distortion and cocktail effect endowing tunable electronic structures pave the new direction for RABs and other multivalent ion batteries.
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DOI
高影响因子
Advanced Energy Materials
·
2024
·Vol. 14
·期 26
·2401114
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IF 24.4
Qin Li,Junjie Ma,Xuanchen Xu,Peng Gao,Meng Cai,Mengqi Han,Jing Yang,Yiqiang Zhang,Yanlin Song
The improvement of photovoltaic and stability performance of tin (Sn)-based halide perovskite solar cells is impeded by notorious oxidation issues and Anderson localization. Despite previous implements in antioxidation through the incorporation of Lewis base additives, there still exist ongoing uncertainties surrounding its complex interaction mechanisms. A perplexing phenomenon regarding accelerated oxidation in acrylic acid is discovered that deviates from conventional Lewis base–acid reaction. The underlying insights into the deprotonation of acrylic acid followed by the formation of a “tripod” ionic bonding form are provided, which results in amplifying the delocalization effect of electrons of Sn 2+ . Furthermore, with the assistance of acrylamide and acrolein, synergistic enhancement in terms of the antioxidation and suppression of Anderson localization can be achieved — a concept referred to as “Dual Synergistic Engineering”. This suppresses the oxidation of Sn 2+ and reduces Sn 4+ content by ≈76%. Meanwhile, the diffusion length is prolonged significantly from 195.9 to 458.9 nm. The optimized all-inorganic Sn/Pb-based perovskite solar cells exhibit a power conversion efficiency of above 14% with enhanced stability. These findings provide an alternative viewpoint for comprehending the impact of chemical interaction on oxidation and crystal growth in Sn/Pb-based perovskites.
研究领域:
材料科学
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光伏技术
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钙钛矿太阳能电池
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固体物理
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化学键合
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半导体材料
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DOI
高影响因子
危险品化学品经营许可证（带存储）