Synthesis of vanadium based binary oxides with a yolk–shell structure and their derived electrocatalysts. Issue 44 (3rd November 2021)

• Record Type: Journal Article
• Authors: Shi, Meiqin; Peng, Fei; Qin, Yu; Li, Fengjiao; Nie, Yuanhang; Fang, Jun; Lang, Xiaoling; Mao, Xinbiao
• Is Part Of: Journal of materials chemistry. Volume 9:Issue 44(2021)
• Page Start: 25051
• Page End: 25061
• Publication Date: 2021-11-03
• Subjects: Materials -- Research -- Periodicals; Chemistry, Analytic -- Periodicals; Environmental sciences -- Research -- Periodicals; 543.0284
• DOI: 10.1039/d1ta06243c
• Languages: English
• ISSNs: 2050-7488

Abstract

Abstract : Tungsten–vanadium sulfide/oxides with yolk–shell structure were formed and exhibited significant catalytic activity towards the HER and ORR. This method is employed to construct composition-tunable binary metal composites with yolk–shell structure. Abstract : The design and synthesis of non-precious metal composite catalysts with a yolk–shell structure and diverse compositions are challenges in materials science for energy conversion. In this work, we established a facile method to synthesize a series of transition metal oxides with yolk–shell structures (YS structures) by combination of Ostwald ripening and the Kirkendall effect. VO(acac)2 and other transition metal chlorides were chosen deliberately as the interfusion couple for the development of the YS structure. Among all transition binary metal oxides, WVO x has a distinct YS structure which can be preserved well in the following sulfurization. The resultant WS2 –V2 O3 and WS2 –V3 S4 yolk–shell spheres were certified to be competitive catalyst candidates for the HER and ORR respectively, due to compositional tuning and the YS structures. The fabricated WS2 –V2 O3 catalyst exhibits excellent HER electrocatalytic activity with a Tafel slope of 87 mV dec −1 and a small overpotential of 89 mV to reach 10 mA cm −2 . The ORR catalyst WS2 –V3 S4 shows remarkable activity with a positive onset potential of 0.95 V and lower Tafel slope of 51 mV dec −1 .