Accelerating multielectron reduction at CuxO nanograins interfaces with controlled local electric field

Weihua Guo; Siwei Zhang; Junjie Zhang; Haoran Wu; Yangbo Ma; Yun Song; Le Cheng; Liang Chang; Geng Li; Yong Liu; Guodan Wei; Lin Gan; Minghui Zhu; Shibo Xi; Xue Wang; Boris I Yakobson; Ben Zhong Tang; Ruquan Ye

doi:10.1038/s41467-023-43303-1

Accelerating multielectron reduction at Cu_xO nanograins interfaces with controlled local electric field

Nat Commun. 2023 Nov 15;14(1):7383. doi: 10.1038/s41467-023-43303-1.

Authors

Weihua Guo^#^{1

2}, Siwei Zhang^#³, Junjie Zhang⁴, Haoran Wu⁵, Yangbo Ma¹, Yun Song¹, Le Cheng¹, Liang Chang⁶, Geng Li¹, Yong Liu¹, Guodan Wei⁶, Lin Gan⁶, Minghui Zhu⁷, Shibo Xi⁸, Xue Wang⁹, Boris I Yakobson¹⁰, Ben Zhong Tang^{11

12}, Ruquan Ye^{13

14}

Affiliations

¹ Department of Chemistry, State Key Laboratory of Marine Pollution, City University of Hong Kong, Hong Kong, 999077, China.
² City University of Hong Kong Shenzhen Research Institute, Shenzhen, 518057, Guangdong, China.
³ Department of Chemistry and the Hong Kong Branch of Chinese National Engineering Research Center for Tissue Restoration and Reconstruction, The Hong Kong University of Science and Technology, Hong Kong, 999077, China.
⁴ Department of Materials Science and Nano Engineering, Rice University, 6100 Main Street, Houston, TX, 77005, USA.
⁵ State Key Laboratory of Chemical Engineering, East China University of Science and Technology, Shanghai, 200237, China.
⁶ Institute of Materials Research, Tsinghua Shenzhen International Graduate School, Tsinghua University, Shenzhen, 518055, Guangdong, China.
⁷ State Key Laboratory of Chemical Engineering, East China University of Science and Technology, Shanghai, 200237, China. minghuizhu@ecust.edu.cn.
⁸ Institute of Chemical and Engineering Sciences, A*STAR, Singapore, 627833, Singapore. xi_shibo@ices.astar.edu.sg.
⁹ School of Energy and Environment, City University of Hong Kong, Hong Kong, 999077, China.
¹⁰ Department of Materials Science and Nano Engineering, Rice University, 6100 Main Street, Houston, TX, 77005, USA. biy@rice.edu.
¹¹ Department of Chemistry and the Hong Kong Branch of Chinese National Engineering Research Center for Tissue Restoration and Reconstruction, The Hong Kong University of Science and Technology, Hong Kong, 999077, China. tangbenz@cuhk.edu.cn.
¹² School of Science and Engineering, Shenzhen Institute of Aggregate Science and Technology, The Chinese University of Hong Kong, Shenzhen, 518172, Guangdong, China. tangbenz@cuhk.edu.cn.
¹³ Department of Chemistry, State Key Laboratory of Marine Pollution, City University of Hong Kong, Hong Kong, 999077, China. ruquanye@cityu.edu.hk.
¹⁴ City University of Hong Kong Shenzhen Research Institute, Shenzhen, 518057, Guangdong, China. ruquanye@cityu.edu.hk.

^# Contributed equally.

Abstract

Regulating electron transport rate and ion concentrations in the local microenvironment of active site can overcome the slow kinetics and unfavorable thermodynamics of CO₂ electroreduction. However, simultaneous optimization of both kinetics and thermodynamics is hindered by synthetic constraints and poor mechanistic understanding. Here we leverage laser-assisted manufacturing for synthesizing Cu_xO bipyramids with controlled tip angles and abundant nanograins, and elucidate the mechanism of the relationship between electron transport/ion concentrations and electrocatalytic performance. Potassium/OH^- adsorption tests and finite element simulations corroborate the contributions from strong electric field at the sharp tip. In situ Fourier transform infrared spectrometry and differential electrochemical mass spectrometry unveil the dynamic evolution of critical *CO/*OCCOH intermediates and product profiles, complemented with theoretical calculations that elucidate the thermodynamic contributions from improved coupling at the Cu⁺/Cu²⁺ interfaces. Through modulating the electron transport and ion concentrations, we achieve high Faradaic efficiency of 81% at ~900 mA cm^-2 for C₂₊ products via CO₂RR. Similar enhancement is also observed for nitrate reduction reaction (NITRR), achieving 81.83 mg h^-1 ammonia yield rate per milligram catalyst. Coupling the CO₂RR and NITRR systems demonstrates the potential for valorizing flue gases and nitrate wastes, which suggests a practical approach for carbon-nitrogen cycling.

Grants and funding

2022A1515011333/Natural Science Foundation of Guangdong Province (Guangdong Natural Science Foundation)