Three-dimensional N-doped carbon nanosheets loaded with heterostructured Ni/Ni 3 ZnC 0.7 nanoparticles for selective and efficient CO 2 reduction

• Published in: Nanoscale 2024-04, Vol.16 (16), p.8119-8131
• Main Authors: Liao, Li, Jia, Chunguang, Wu, Songjiang, Yu, Shenjie, Wen, Zhenhai, Ci, Suqin
• Format: Article
• Language: English
• ISSN: 2040-3364; 2040-3372
• DOI: 10.1039/D3NR05771B

Electrocatalytic CO reduction (CO RR) has emerged as a promising approach for converting CO into valuable chemicals and fuels to achieve a sustainable carbon cycle. However, the development of efficient electrocatalysts with high current densities and superior product selectivity remains a significant challenge. In this study, we present the synthesis of a porous nitrogen-doped carbon nanosheet loaded with heterostructured Ni/Ni ZnC nanoparticles through a facile hydrothermal-calcination method (Ni/Ni ZnC -NC). Remarkably, the Ni/Ni ZnC -NC catalyst exhibits outstanding performance towards CO RR in an H-cell, demonstrating a high CO faradaic efficiency of 92.47% and a current density ( ) of 15.77 mA cm at 0.87 V RHE. To further explore its potential industrial applications, we constructed a flow cell and a rechargeable Zn-CO flow cell utilizing the Ni/Ni ZnC -NC catalyst as the cathode. Impressively, not only does the Ni/Ni ZnC -NC catalyst achieve an industrial high current density of 254 mA cm at a voltage of -1.19 V RHE in the flow cell, but it also exhibits a maximum power density of 4.2 mW cm at 22 mA cm in the Zn-CO flow cell, while maintaining excellent rechargeability. Density functional theory (DFT) calculations indicate that Ni/Ni ZnC -NC possesses more spontaneous reaction pathways for CO reduction to CO, owing to its heterogeneous structure in contrast to Ni ZnC -NC and Ni-NC. Consequently, Ni/Ni ZnC -NC demonstrates accelerated CO RR reaction kinetics, resulting in improved catalytic activity and selectivity for CO RR.