Atomically Dispersed NiN3 Sites on Highly Defective Micro‐Mesoporous Carbon for Superior CO2 Electroreduction. Issue 20 (20th April 2022)

• Record Type: Journal Article
• Authors: Fu, Xianzhang; Zhang, Pianpian; Sun, Tingting; Xu, Lianbin; Gong, Lei; Chen, Baotong; Xu, Qingmei; Zheng, Tianyu; Yu, Zonghua; Chen, Xin; Zhang, Shaolong; Hou, Minchen; Wang, Hailong; Wang, Kang; Jiang, Jianzhuang
• Is Part Of: Small. Volume 18:Issue 20(2022)
• Page Start: n/a
• Page End: n/a
• Publication Date: 2022-04-20
• Subjects: CO 2 electroreduction -- coordination environment -- micro‐mesoporous defects -- single atomic Ni sites; Nanotechnology -- Periodicals; Nanoparticles -- Periodicals; Microtechnology -- Periodicals; 620.5
• DOI: 10.1002/smll.202107997
• Languages: English
• ISSNs: 1613-6810

Abstract

Abstract: Direct electrochemical conversion of CO2 to CO product powered by renewable electricity is widely advocated as an emerging strategy for alleviating CO2 emissions while addressing global energy issues. However, the development of low‐cost and efficient electrocatalysts with high Faradaic efficiency for CO production (FECO ) and high current density remains a grand challenge. Herein, a robust single nickel atomic site electrocatalyst, which features isolated and dense single atomic NiN3 sites anchored on highly defective hierarchically micro‐mesoporous carbon (Ni‐SAs/HMMNC‐800), to enable enhanced charge transport and more exposed active sites for catalyzing electrochemical CO2 ‐to‐CO conversion, is reported. The Ni‐SAs/HMMNC‐800 catalyst achieves excellent activity and selectivity with high FECO values of >90% throughout a wide potential range (the FECO reaches 99.5% at −0.7 V vs reversible hydrogen electrode) and a CO partial current density as high as 13.0 mA cm −2 at −0.7 V versus reversible hydrogen electrode, as well as a far outstanding durability during long‐term continuous operation, indicating a superior CO2 electroreduction performance than that of other reference samples and most of previously reported carbon‐based single atom electrocatalysts. Experimental and density functional theory calculations reveal that atomic NiN3 coordination sites coupled adjacent defects are favorable to significantly enhancing the formation of COOH* reaction intermediates while suppressing the competing hydrogen evolution reaction, thereby enhancing the electrocatalytic activity for CO2 ‐to‐CO reduction. Notably, this work provides a valuable new prospect for designing and synthesizing efficient and cost‐effective single atom CO2 electroreduction catalysts for practical applications. Abstract : This work develops a single‐atom Ni catalyst with abundant isolated atomic NiN3 sites and adjacent rich micro‐mesoporous defects for catalyzing CO2 ‐to‐CO electroreduction. Benefiting from the cooperation of atomically dispersed NiN3 coordination species as active sites for catalytic reactions, and the adjacent enhanced micro‐mesoporous defects for greatly improving mass/charge‐transfer capability and active‐site accessibility, the optimal Ni‐SAs/HMMNC‐800 catalyst exhibits superior electrocatalytic CO2 RR activity and selectivity with a ultrahigh FECO (≈99.5%), and high durability under long‐period CO2 RR operation.