Journal of Power Sources 445 (2020) 227280 Available online 24 October 2019 0378-7753/© 2019 Elsevier B.V. All rights reserved. Short communication Effcient oxygen reduction activity on layered palladium phosphosulphide and its application in alkaline fuel cells Sujoy Sarkar , Shubham Patel , S. Sampath * Department of Inorganic and Physical Chemistry, Indian Institute of Science, Bangalore, 560012, India HIGHLIGHTS G R A P H I C A L ABSTRACT � A ternary layered PdPS is employed as a catalyst for ORR in alkaline medium. � The ORR is found to occur through a direct four electron pathway. � PdPS has been used as cathode catalyst in anion exchange membrane fuel cell. � A peak power density of 340 mWcm 2 at 60 � C is observed for the AEMFC. � Performance in fuel cell is quite com- parable to that of Pt/C under similar conditions. A R T I C L E INFO Keywords: Palladium phosphosulphide Oxygen reduction reaction Anion exchange membrane fuel cell Electrocatalyst ABSTRACT Metal chalcogenides-based electrocatalysts have received considerable attention in recent years. Herein, a layer- type ternary chalcogenide compound, PdPS is proposed as an effcient oxygen reduction reaction electrocatalyst in alkaline medium. PdPS is semiconducting that crystallizes in orthorhombic symmetry. Improvement in con- ductivity of PdPS using reduced graphene oxide results in excellent electrocatalytic activity. The kinetics is followed by rotating (ring) disk electrode measurements and the composite electrocatalyst is found to be stable, effcient and methanol tolerant. The catalyst is further used as cathode in anion exchange membrane fuel cell and is shown to deliver power density comparable to Pt/C catalyst. In addition, this catalyst is also capable of water oxidation from alkaline solution with favorable electrochemical parameters. 1. Introduction In view of the increasing energy consumption and levels of green- house gases, there is a need for alternative energy sources that will be used to provide clean and environmentally friendly solutions [1]. Fuel cells [2,3] have been prescribed as alternative energy systems for several years but suffer from certain problems associated with sluggish kinetics of ORR that limits their performance [4–6]. Alkaline fuel cell (AFC) that uses aqueous KOH as the electrolyte, overcomes the problems to certain extent, but still improvements are necessary both in the membrane as well as in the catalyst components to achieve good performance [7,8]. Platinum as well as non-Pt based catalysts have been reported for ORR in the literature [9–11]. Among the non-Pt electrocatalysts, tran- sition metals [12,13], metal carbides [14,15], oxides [16], nitrides [17, 18] have been well explored. Metal chalcogenides (M a X b , M ¼ Mo, Co, Ru, Fe, Ni etc, X ¼ S, Se,Te) have been recognized as promising candi- dates owing to their potential in electrochemical energy conversion and storage systems [19–24]. Chalcogenides are very often tolerant to * Corresponding author. E-mail address: sampath@iisc.ac.in (S. Sampath). Contents lists available at ScienceDirect Journal of Power Sources journal homepage: www.elsevier.com/locate/jpowsour https://doi.org/10.1016/j.jpowsour.2019.227280 Received 9 May 2019; Received in revised form 4 October 2019; Accepted 8 October 2019