CHEMICAL ENGINEERING JOURNAL
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2024
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IF 13.3
He Xiao,Wenxiang Wang,Man Zhao,Zimei Fu,Meng Bai,Li Zhang,Junming Zhang,Ergui Luo,Jian Zhang,Haishun Wu,Jianfeng Jia
Cut-lost, highly active and stable (photo-)electrocatalysts are earnestly expected to overcome high energy obstacles in methanol oxidation reaction (MOR). A hybrid of NiW/graphene (NiW/G) is prepared by a simple self-designed electrosynthesis method. During the process of electrosynthesis, exfoliation of bulky graphite into graphene and generation of multivalent NiW bimetal precursor are both achieved. This obtained composite displays superior photoelectrocatalytic performance towards MOR. As for NiW/G-light, its area activity (peak current) and mass activity (peak current) are up to 343.4 mA cm −2 and 5960.7 mA mg −1 respectively, much higher than NiW/G, Ni/G and W/G. Operando electrochemical impedance spectroscopy, in-situ Fourier transform infrared spectroscopy and other ex-situ techniques uncover that the excellent MOR performance for NiW/G-light results from synergetic modulation of nickel sites by introducing tungsten and light, which provides desired adsorption behavior and high electrochemical active surface area. It’s found that introduction of W component promotes the formation of W-O-Ni(Ni 3+ ) species, supporting more strong adsorption sites for methanol. This results in new reaction path between adsorbed methanol and OH* for producing formic acid. With application of light, the photo-generated hole promotes oxidation of residual Ni 2+ into Ni 3+ species, which provides additional formed NiOOH sites for MOR. It’s concluded introduction of tungsten and light is efficient for greatly enhancing methanol electrooxidation. This work is highly instructive for application of self-designed electrosynthesis method to construct dimetal/graphene composite and photoelectric synergistic catalysis towards MOR.
研究领域:
材料科学
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电化学
✓ 已验证
产品关联
DOI
高影响因子
Nano Energy
·
2024
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IF 16.8
Shanyong Chen,Tao Luo,Xiaoqing Li,Kejun Chen,Qiyou Wang,Junwei Fu,Kang Liu,Chao Ma,Ying-Rui Lu,Hongmei Li,Kishan S. Menghrajani,Changxu Liu,Stefan A. Maier,Ting-Shan Chan,Min Liu
Metal-nitrogen-carbon single-atom catalysts (SACs) have emerged as promising candidates for electrocatalytic CO 2 reduction reaction. However, the perpendicular d z 2 orbital within planar metal site mainly interacts with *COOH, resulting in inferior CO 2 activation. Inspired by reaction-driven active configuration, here we propose to upshift nickel single-atom away from nitrogen-carbon substrate, prominently promoting the interaction between CO 2 and other d orbitals besides d z 2 . Theoretical and experimental analyses reveal that upshifting nickel site away substrate induces d xz , d yz , and d z 2 to hybridize with CO 2 , expediting CO 2 conversion to *COOH. The planar and out-of-plane Ni-N sites are formed on carbon nanosheet (Ni 1 -N/C NS ) and curved nanoparticle (Ni 1 -N/C NP ), respectively, which is verified by X-ray absorption fine structure spectroscopy. Impressively, the Ni 1 -N/C NP presents CO Faradaic efficiency of 96.4 % at 500 mA cm −2 and energy conversion efficiency of 79.8 % in flow cell, outperforming Ni 1 -N/C NS and most SACs. This work highlights the simulation of reaction-driven active sites for efficient electrocatalysis .
研究领域:
材料科学
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电化学
✓ 已验证
产品关联
DOI
高影响因子
APPLIED SURFACE SCIENCE
·
2025
·
IF 6.9
Quanxiao Deng,Dezhong Song,Youzhen Liu,Ruizhi Yin,Chunyan Liu,Jia Huo
Carbon-based single-atom catalysts have demonstrated excellent performance in electrochemical CO 2 reduction reactions. However, the traditional planar, highly symmetric MN 4 structures seriously restrict their activities due to relatively weak interactions between the catalyst and CO 2 . In this work, we demonstrated a novel and controllable method for axial P coordination of single-atom Ni catalyst through low-temperature post-functionalization. This modification significantly regulates the spin state of the Ni sites, thereby increasing the interaction between CO 2 and the active sites. The axially P-coordinated single-atom Ni catalyst exhibits markedly improved performance for CO 2 conversion to CO, achieving a maximum CO Faradaic efficiency of ∼ 99 % at −0.98 V (vs. RHE) and a partial current density for CO of −45.1 mA cm −2 at −1.48 V (vs. RHE), which is 18.4 % higher than that of the pristine single-atom Ni catalyst. Density functional theory calculations indicate that axial P coordination modulates the magnetic moment of the Ni active center and the 3d orbital splitting energy levels, thereby promoting CO 2 adsorption and facilitating CO desorption by optimizing the binding energies of reaction intermediates. These findings are confirmed by experimental electron spin resonance measurements. This work provides a facile strategy for regulating the electronic structures of single-atom catalysts and highlights the potential for spin-state modulation to significantly enhance CO 2 electroreduction.
研究领域:
材料科学
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电化学
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理论计算
✓ 已验证
产品关联
DOI
高影响因子
ACS Nano
·
2025
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IF 16
Kang Lian,Sanshuang Gao,Wenxian Liu,Qian Liu,Yanhong Feng,Jun Luo,Guangzhi Hu,Ke Chu,Dingsheng Wang,Xijun Liu
The combination of CO2 fixation and small organic molecule oxidation offers a promising solution to increasing severe environmental issues and energy crises. Here, low-coordinated NiN3 sites were anchored onto nitrogen-doped ordered mesoporous carbon (Ni-SAs/NOMC), which is capable of efficiently catalyzing the coupled methanol oxidation reaction and CO2 reduction reaction (MOR||CO2RR), thereby reducing the energy required for CO2 conversion and enhancing the economic value of the CO2 electrolytic system. In the membrane electrode assembly electrolyzer-based MOR||CO2RR, Ni-SAs/NOMC achieved Faradaic efficiencies (FEs) of 95.4% for formate at the anode and 96.3% for CO at the cathode. Moreover, at a current density of 0.8 A cm–2, Ni-SAs/NOMC demonstrated stable electrolysis for up to 100 h, with FEs at both the anode and cathode remaining stable at approximately 90%. In situ spectroscopy analyses and theoretical calculations identified the formation of critical intermediate species and the origin of activity improvement, guiding the development of efficient electrosynthesis of valuable chemicals.
研究领域:
能源化学
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环境科学
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材料科学
✓ 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）