化石燃料的燃烧导致大气中二氧化碳(CO2)的浓度迅速上升,并引发了严重的能源、环境危机。由可再生电力驱动的电催化CO2还原为增值化学品和燃料是解决当前化石燃料枯竭的一种有效方法。采用“一锅法”制备了磷(P)修饰的高分散性“钴-氮-碳”(Co-N-C/P)催化剂,通过扫描电子显微镜(SEM)、X射线衍射(XRD)、拉曼光谱(Raman)和X射线光电子能谱(XPS)等手段对催化剂的形貌、元素分布、缺陷程度、表面元素价态及配位结构进行了表征,并考察了其在H型电解槽中电催化CO2还原为CO的性能。测试结果表明,所制备的Co-N-C/P催化剂在-0.9Vvs.RHE的外加电位下具有97.0%的CO法拉第效率(FECO),电流密度为4.58mA/cm2,并可以进行26h的稳定性测试。与Co-N-C催化剂相比,P的掺杂更有利于Co原子在碳黑基底上的良好分散,相应的FECO提高了约38.9%,说明P的掺杂有效提高了Co-N-C催化剂的电催化CO2还原为CO的性能。

The burning of fossil fuels has led to a rapid increase in the concentration of carbon dioxide(CO2) in the atmosphere, resulting in a serious energy and environmental crisis. Electrocatalytic re-duction of CO2 to value-added chemicals and fuels, driven by renewable electricity, is an effectivemethod for addressing the current depletion of fossil fuels. In this paper, a phosphorus-modified highlydispersible cobalt-nitrogen-carbon (Co-N-C) catalyst was prepared using a " one-pot" method. Thecatalyst′s morphology, element distribution, defect degree, surface element valence and coordinationstructure were characterized using scanning electron microscopy (SEM), X-ray diffraction (XRD),Raman spectroscopy, and X-ray photoelectron spectroscopy (XPS). The performance of the catalyst inthe electrocatalytic reduction of CO2 to CO in an H-type cell was investigated. The results showed thatthe prepared Co-N-C / P catalyst exhibited a 97.0% CO Faraday Efficiency (FECO) at an applied po-tential of -0.9 V vs. RHE, with a current density of 4.58 mA/ cm2, and demonstrated stability over a26-hour test. Compared with the Co-N-C catalysts, the P-dopant facilitated a good dispersion of Coatoms on the carbon black substrate, resulting in an approximately 38.9% increase in FECO. Thesefindings demonstrated that the P-dopant significantly enhanced the performance of Co-N-C catalystseffectively for the electrocatalytic reduction of CO2 to CO.