N-doped graphene anchored ultrasmall Ir nanoparticles as bifunctional electrocatalyst for overall water splitting

Autor: Wenqing Yao, Xian Jiang, Yulian Li, Cuiting Zhao, Linfei Ding, Dongmei Sun, Yawen Tang
Jazyk: angličtina
Rok vydání: 2022
Předmět:
Zdroj: Green Energy & Environment, Vol 7, Iss 5, Pp 1111-1118 (2022)
Druh dokumentu: article
ISSN: 2468-0257
DOI: 10.1016/j.gee.2021.01.011
Popis: Seeking for extremely active and durable bifunctional electrocatalysts towards the overall water splitting possesses a strategic significance on the development of sustainable and clean energy for the replacement of fossil fuels. Ir-based nanomaterials are deemed as one of the most high-efficiency oxygen evolution reaction electrocatalysts while the hydrogen evolution reaction performance is unfavorable. In this work, we report a one-pot hydrothermal synthesis of N-doped graphene anchored Ir nanoparticles (Ir/N-rGO) with ultrasmall particle size (∼2.0 nm). Apart from the predictably superior OER performance, the resultant Ir/N-rGO also displays excellent hydrogen evolution reaction (HER) performance, requiring merely 76 and 260 mV overpotentials to achieve the current density of 10 mA cm−2 towards HER and OER, respectively. When applied as the bifunctional electrodes for overall water splitting, Ir/N-rGO needs a lower overpotential (1.74 V) to achieve a current density of 50 mA cm−2 in alkaline solution, exceeding that of Pt/C and RuO2 couple (1.85 V). Thus, the as-fabricated Ir/N-rGO has a commendable prospect in the practical application of alkaline water electrocatalysis.
Databáze: Directory of Open Access Journals