CHEMICAL ENGINEERING JOURNAL
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2025
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IF 13.2
Nana Zhou,Yurong Yin,Baojuan Luo,Yongxin Fu,Xiaoxun Ma,Chengyi Dai
The electrochemical CO 2 reduction reaction (eCO 2 RR), which is well suited for reducing atmospheric CO 2 levels and generating clean energy. Water is the main proton source in the electrochemical reduction process. However, water features a high dissociation energy barrier, and most protons are involved in HER, so that only a small amount of H + is used in the CO 2 reduction reaction. Herein, we reveal that appropriately chosen ligands on the catalyst surface can abstract protons from water, store them, and transfer them to CO 2 to promote the formation of COOH and improve the proton utilization efficiency of the eCO 2 RR. Moreover, the activity of the ligand complexed protons is shown to be lower than that of free ones and thus result in HER inhibition our ligands with different pK a values (i.e., proton release capacities) are used to functionalize ZnO, and the plot of pK a vs. the FE CO exhibits a volcano shape. Overly small pK a leads to the combination of abundant protons with each other and the dominance of the HER, whereas overly large pK a does not promote the utilization of H + by CO 2 . Ligands with suitable pK a can properly bind and release protons, which is conducive to the formation of *COOH, thus accelerating eCO 2 RR. In particular, mercaptobenzoic acid (MBA) considerably enhances catalytic activity because of its moderate pK a (FE CO = 90 %, which is 2 times higher than the FE CO of unmodified ZnO, and j CO is nearly 5 times higher). In situ infrared spectroscopic analysis proves that the above ligand can abstract protons from H 2 O and then release them, promoting the dissociation of H 2 O. Theoretical calculations show that pK a affects the ability of ligands to abstract and release protons.
研究领域:
材料科学
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电化学
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催化反应
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产品关联
DOI
高影响因子
DALTON TRANSACTIONS
·
2023
·Vol. 52
·期 33
·11631-11637
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IF 4
Yunni Liu,Yinghao Tao,Zhaobing Lu,Jing Teng,Weiju Hao,Jun Lin,Guisheng Li
The electrocatalytic nitrogen reduction reaction (NRR) to ammonia is a promising technology to store renewable energy and mitigate greenhouse gas emissions. However, it usually suffers from low ammonia yield and selectivity because of the lack of efficient electrocatalysts. Herein, we report that the construction of metal phosphide heterojunctions is an efficient strategy for NRR activity enhancement. A CoP–MoP heterojunction electrocatalyst, which is fabricated by a facile NaCl template-assisted strategy, exhibits a favorable ammonia yield rate of 77.8 μg h−1 mgcat−1 (38.9 μg h−1 cm−2) and a high faradaic efficiency of 11.16% at −0.50 V versus the reversible hydrogen electrode. The high NRR electrocatalytic activity can be attributed to the electronic coupling effects and interfacial synergistic effects of CoP and MoP at the heterojunction interface, which accelerates the electron transfer rate. Moreover, Mo doping changes the d-band centers of metal sites on the CoP surface, which is conducive to N2 adsorption and promotes N2* adsorption in the competition of occupying active sites, thus inhibiting the HER. This work manifests the high potential of phosphide electrocatalysts and opens an alternative route toward NRR electrocatalysis.
研究领域:
材料科学
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电化学
✓ 已验证
产品关联
DOI
PubMed
高影响因子
ACS Sustainable Chemistry & Engineering
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2020
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IF 7.632
Haidong Yang,Yang Liu,Yutong Luo,Shiqing Lu,Bitao Su,Jiantai Ma
Electrocatalytic nitrogen reduction reaction (NRR) represents a highly promising process to ammonia synthesis for artificial N2 fixation. However, the yield rate for NH3 production and Faradaic efficiency (FE) are still low, which greatly hinder its widespread applications. Until now, although a variety of catalysts, including single-atom catalysts, have been developed for NRR in the pursuit of suppressing hydrogen evolution reaction (HER) and the corresponding higher FE, the limited NH3 yield rate makes them uncompetitive for the synthesis of ammonia. Herein, we report a Fe single-atom catalyst anchoring on a nitrogen-doped carbon substrate (Fe SAC/N–C) as a highly efficient NRR catalyst. The catalyst achieves a high FE of 39.6% in 0.1 M KOH under room temperature, particularly a dramatically enhanced NH3 yield rate of 53.12 μgNH3 h–1 mgcat–1. The isotopic labeling (15N2) experiment confirms that the NH3 production completely originates from N2 reduction. Meanwhile, theoretical calculations and X-ray fine structure analysis reveal that the Fe–N3 coordination of Fe SAC/N–C is indeed responsible for the suppression of HER, particularly resulting in a maximum activation of NRR intermediates to produce ammonia with a high yield rate.
研究领域:
电催化
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材料科学
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化学工程
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产品关联
DOI
高影响因子
RSC Advances
·
2019
·Vol. 9
·期 19
·10635-10644
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IF 3.049
Xiaoxu Xuan,Jun Cheng,Xiao Yang,Junhu Zhou,Kefa Cen
Carbon supported nano-metal catalysts are expected to improve CO2 reduction selectivity and efficiency due to the addition of more active sites and enhancement of electron transport ability. In this study, HKUST-1 was pyrolyzed and decorated with Pt to prepare Pt–Cu/C catalysts. The catalytic effect of the catalysts with different Pt contents in the CO2 photoeletrochemical reduction reaction (CO2PRR) were compared. The total carbon atom conversion rate in CO2PRR experiments using Pt–Cu/C catalysts first increased to a peak when using 1.6 wt% Pt–Cu/C catalyst and then decreased with the increase of Pt content. The 1.6 wt% Pt–Cu/C catalyst showed good hydrogen evolution reaction (HER) inhibiting ability compared with other Pt–Cu/C catalysts. Density functional theory (DFT) calculations were conducted to give an insight into the CO2PRR mechanism on some possible active sites in Pt–Cu/C catalysts. The result demonstrated that HER was more likely to be inhibited on the Cu/Pt active surface and at the same time CO2PRR was promoted.
研究领域:
材料科学
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环境科学
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催化化学
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产品关联
DOI
PubMed
高影响因子
Nature Communications
·
2021
·Vol. 12
·期 1
·1-11
·
IF 14.919
Sun Hao,Chen Ling,Xiong Likun,Feng Kun,Chen Yufeng,Zhang Xiang,Yuan Xuzhou,Yang Baiyu,Deng Zhao,Liu Yu,Rümmeli Mark H.,Zhong Jun,Jiao Yan,Peng Yang
Electrochemical CO 2 reduction (CO 2 RR) in a product-orientated and energy-efficient manner relies on rational catalyst design guided by mechanistic understandings. In this study, the effect of conducting support on the CO 2 RR behaviors of semi-conductive metal-organic framework (MOF) — Cu 3 (HITP) 2 are carefully investigated. Compared to the stand-alone MOF, adding Ketjen Black greatly promotes C 2 H 4 production with a stabilized Faradaic efficiency between 60-70% in a wide potential range and prolonged period. Multicrystalline Cu nano-crystallites in the reconstructed MOF are induced and stabilized by the conducting support via current shock and charge delocalization, which is analogous to the mechanism of dendrite prevention through conductive scaffolds in metal ion batteries. Density functional theory calculations elucidate that the contained multi-facets and rich grain boundaries promote C–C coupling while suppressing HER. This study underlines the key role of substrate-catalyst interaction, and the regulation of Cu crystalline states via conditioning the charge transport, in steering the CO 2 RR pathway.
研究领域:
电化学
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材料科学
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催化
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能源转换
✓ 已验证
产品关联
DOI
PubMed
高影响因子
危险品化学品经营许可证（带存储）