湖南大学王双印团队的开发了用于高效电催化NO还原制NH₃的六方钴纳米片。相关研究成果于2023年3月14日发表在国际顶尖学术期刊《美国化学会杂志》。

电催化一氧化氮（NO）还原不仅为环境NH₃生成提供了一种非常有前途的策略，而且还缓解了人为破坏的N循环平衡。然而，探索有效的电催化剂以提高NO电还原性能仍然是一个重大挑战。

该文中，研究人员制备了六方紧密堆积的Co纳米片（hcp-Co），其NH₃产率为439.50μmol cm^–2 h^–1，法拉第效率为72.58%，优于Co纳米片的面心立方相（fcc-Co）和大多数报道的电催化剂。通过密度泛函理论计算和NO温度程序脱附实验的结合，hcp-Co上优异的催化NO还原反应（NORR）活性可归因于独特的电子结构和质子穿梭效应。研究人员组装了一个使用hcp Co作为阴极的Zn–NO电池概念验证装置，其功率密度为4.66 mW cm^–2，优于目前文献中报道的性能。

附：英文原文

Title: Hexagonal Cobalt Nanosheets for High-Performance Electrocatalytic NO Reduction to NH3

Author: Dongdong Wang, Zhi-Wen Chen, Kaizhi Gu, Chen Chen, Yingying Liu, Xiaoxiao Wei, Chandra Veer Singh, Shuangyin Wang

Issue&Volume: March 14, 2023

Abstract: Electrocatalytic nitric oxide (NO) reduction not only provides an extremely promising strategy for ambient NH3 generation but also alleviates the artificially disrupted N-cycle balance. However, exploring efficient electrocatalysts to enhance the NO electroreduction performance remains a significant challenge. Herein, a hexagonal-close-packed Co nanosheet (hcp-Co) is prepared and exhibits a high NH3 yield of 439.50 μmol cm–2 h–1 and a Faraday efficiency of 72.58%, outperforming the face-centered cubic phase of the Co nanosheet (fcc-Co) and most reported electrocatalysts. Through the combination of density functional theory calculations and NO temperature-programmed desorption experiments, the superior catalytic NO reduction reaction (NORR) activity on the hcp-Co can be attributed to the unique electron structures and proton shuttle effect. A proof-of-concept device of Zn–NO batteries using the hcp-Co as the cathode is assembled and shows a power density of 4.66 mW cm–2, which is superior to the reported performance in the literature so far.

DOI: 10.1021/jacs.3c00276

Source: https://pubs.acs.org/doi/10.1021/jacs.3c00276