Nanoporous B13C2 towards Highly Efficient Electrochemical Nitrogen Fixation. Issue 39 (22nd August 2021)

• Record Type: Journal Article
• Authors: Lan, Jiao; Luo, Min; Han, Jiuhui; Peng, Ming; Duan, Huigao; Tan, Yongwen
• Is Part Of: Small. Volume 17:Issue 39(2021)
• Page Start: n/a
• Page End: n/a
• Publication Date: 2021-08-22
• Subjects: boron carbide -- electrochemical nitrogen fixation -- nanoporous -- selective etching; Nanotechnology -- Periodicals; Nanoparticles -- Periodicals; Microtechnology -- Periodicals; 620.5
• DOI: 10.1002/smll.202102814
• Languages: English
• ISSNs: 1613-6810

Abstract

Abstract: The electrochemical nitrogen fixation under mild conditions is a promising alternative to the current nitrogen industry with high energy consumption and greenhouse gas emission. Here, a nanoporous boron carbide (np‐B13 C2 ) catalyst is reported for electrochemical nitrogen fixation, which is fabricated by the combination of metallurgical alloy design and chemical etching. The resulting np‐B13 C2 exhibits versatile catalytic activities towards N2 reduction reactions (NRR) and N2 oxidation reaction (NOR). A high NH3 yield of 91.28 µ g h −1 mgcat. −1 and Faradaic efficiency (FE) of 35.53% at −0.05 V versus the reversible hydrogen electrode are obtained for NRR, as well as long‐term stability of up to 70 h, making them among the most active NRR electrocatalysts. This catalyst can also achieve a NO3 − yield of 165.8 µ g h −1 mgcat. −1 and a FE of 8.4% for NOR. In situ Raman spectroscopy and density functional theory calculations reveal that strong coupling between the BC sites modulates the electronic structures of adjacent B atoms of B13 C2, which enables the B sites to effectively adsorb and activate chemical inert N2 molecules, resulting in lowered energy required by the potential‐determining step. Besides, the introduction of carbon can increase the inherent conductivity and reduce the binding energy of the reactants, thus improving N2 fixation performance. Abstract : A nanoporous B13 C2 is fabricated by metallurgical alloy design and chemical etching approach, which can achieve high selectivity and excellent stability towards both NRR and NOR. The strong interaction between BC sites modulates the electronic structures of adjacent B atoms, which enables the B sites to effectively stabilize the transition state and lower the barrier for improving N2 fixation performance.