Efficient electrochemical reduction of nitrate by bimetallic Cu-Fe phosphide derived from Prussian blue analogue

• Published in: Colloids and surfaces. A, Physicochemical and engineering aspects Vol. 658; p. 130678
• Main Authors: Fang, Xin, Tan, Ling, Luo, Haopeng, Jiang, Fang, Chen, Huan
• Format: Journal Article
• Language: English
• Published: Elsevier B.V 05.02.2023
• Subjects: Atomic H; Bimetallic phosphide nanoparticles; catalysts; chlorides; crystal structure; Electrocatalytic nitrate reduction; electrochemistry; Indirect reduction; nanoparticles; nitrates; phosphides; reaction kinetics; species; temperature; Bimetallic phosphide nanoparticles; Atomic H; Indirect reduction; Electrocatalytic nitrate reduction
• ISSN: 0927-7757; 1873-4359
• DOI: 10.1016/j.colsurfa.2022.130678

Designing electrocatalysts for nitrate (NO3-) reduction with excellent activity, low cost and stability is of great interest. Herein we synthesized a novel transition bimetallic phosphide (CuFeP-x, x referred to the phosphidation temperature) catalyst by phosphidation using CuFe-Prussian blue analogue (PBA) nanoparticles as the precursor. The obtained CuFeP-450 maintained the morphology of nanocube with the average size of 33.0 nm and bimetallic phosphide nanoparticles formed during the phosphidation process. The higher electrocatalytic activity of CuFeP-x in electrochemical NO3- reduction were attained as compared to that of calcined CuFe-450, because the CuFeP-x have a lower interface impedance and the dominated species for NO3- reduction changes from electron to atomic H* , which effectively enhanced the removal rate. The appropriate phosphidation temperature can form a crystal structure that facilitated reaction kinetics. As a result, CuFeP-450 showed the best electrocatalytic performance for NO3- reduction (99.42%), and the selectivity of N2 can reach nearly 100% under the condition of 1000 mg L−1 chloride ions. This simple method using PBA with binary transition metals to prepare bimetallic phosphide provides a new direction for designing efficient non-noble metal electrocatalysts for NO3- reduction. [Display omitted] •Electrochemical NO3- reduction was achieved by CuFeP-x derived from CuFe-PBA.•Introduction of CuFeP-x by phosphidation promotes electrocatalytic formation of atomic H*.•Synergy of transition bimetals increases the ability of electron-donating.