Oxygen Vacancy‐Enriched Co₃O₄ as Efficient Co‐catalyst for Pt Nanoparticles towards Methanol Electrooxidation

Abstract

Herein, a reduced Co3O4/C (rCo3O4/C) composite with rich oxygen vacancies has been fabricated through facile sodium borohydride reduction treatment to act as an effective promoter for Pt nanoparticles (NPs). The Pt NPs are highly dispersed onto the hybrid support with average size of 1.89 nm. Electrochemical measurements show that the Pt−rCo3O4/C‐2 h catalyst with abundant oxygen vacancies possesses better CO tolerance and stability and exhibits a higher mass activity (MA) of 1412 mA ⋅ mg−1(Pt) than that of pristine Co3O4/C supported Pt nanoparticles (Pt−pCo3O4/C) in acidic medium. The enhanced catalytic performance can be attributed to sodium borohydride reduction enriching the oxygen vacancies of Co3O4, which can generate a large amount of −OH species more easily via hydrolysis to oxidize CO species adsorbed on Pt surface to release Pt active sites. Consequently, the construction of oxygen vacancy‐rich materials as co‐catalysts can deliver excellent catalytic performance for Pt‐based electrocatalysts.

Porous calcium copper titanate electrodes for paracetamol degradation by electro-oxidation via CuO-induced peroxymonosulfate activation

“…The generation of oxygen vacancies may allow producing more active defects, thus enhancing the electrochemical degradation of pollutants. 77,78 Furthermore, based on literature data, the CuO phase promotes PMS activation to produce SO 4 − free radicals, according to eqn (6). 48 In addition, the Cu( ii )–HSO 5 combination might yield both Cu( iii ) and ·OH by an alternative mechanism of one-electron transfer (eqn (7)).…”

Ir-RuOx Nanoparticles on WO3 Ultrafine Nanowires As Catalysts for the Oxygen Evolution Reaction in Acidic Media

“…Additionally, the redistribution of interfacial charges contributes to the improved activity of the catalyst. 46,47 Figure 3b displays the high-resolution Ir 4f spectra of IrO x @ WO 3 and Ir-RuO x @WO 3 samples. In IrO x @WO 3 , the two peaks located at 62.36 and 65.76 eV correspond to Ir 3+ 4f 7/2 and Ir 3+ 4f 5/2 , and the two peaks located at 61.26 and 64.26 eV correspond to the Ir 4+ 4f 7/2 and Ir 4+ 4f 5/2 , respectively.…”