Template assisted synthesis of Ni, N co-doped porous carbon from Ni incorporated ZIF-8 frameworks for electrocatalytic oxygen reduction reaction. (9th July 2020)

• Record Type: Journal Article
• Authors: Priya K., Vaishna; Thomas, Minju; Illathvalappil, Rajith; K., Shijina; Kurungot, Sreekumar; Nair, Balagopal N.; Mohamed, A. Peer; Anilkumar, Gopinathan M.; Yamaguchi, Takeo; Hareesh, U. S.
• Is Part Of: New journal of chemistry. Volume 44:Number 28(2020)
• Page Start: 12343
• Page End: 12354
• Publication Date: 2020-07-09
• Subjects: Chemistry -- Periodicals; Chimie -- Périodiques; 540
• DOI: 10.1039/d0nj01373k
• Languages: English
• ISSNs: 1144-0546

Abstract

Abstract : Ni, N co-doped porous carbon derived from nickel containing ZIF-8 frameworks for enhanced ORR performance in alkaline medium. Abstract : A heteroatom doped porous carbon electrocatalyst with enhanced oxygen reduction reaction (ORR) performance in alkaline medium was obtained by high temperature treatment of Ni incorporated ZIF-8 frameworks and its composite with g-C3 N4 as a supporting matrix template. The morphology and porosity of this heteroatom containing carbon were tuned by varying the Ni : Zn molar ratio in Ni/Zn ZIF-8 and Ni/Zn ZIF-8@g-C3 N4 composites. The template aided synthetic strategy using g-C3 N4 helped in the controlled decomposition of composites leading to a heteroporous sheet like architecture with increased nitrogen content. The Ni/Zn ZIF-8 sample on heat treatment in the 800–1000 °C temperature range led to the formation of Ni, N co-doped porous carbon (Ni-NPC) with Ni–C active sites. The defective sites induced by nickel carbide along with the distributed N atoms on the carbon surface enabled active O2 adsorption sites. The high surface area, high degree of graphitisation as well as the defects created by well dispersed N and Ni on porous carbon matrices favoured charge separation leading to higher electrochemical ORR activity. The Ni, N co-doped carbon catalyst in alkaline medium exhibited a limiting current density of 5.2 mA cm −2 with a half-wave potential of 0.76 V vs. RHE in 0.1 M KOH. The catalyst also showed improved methanol tolerance and better stability compared to the standard Pt/C catalyst.