Cobalt and Nickel Phosphates as Multifunctional Air-Cathodes for Rechargeable Hybrid Sodium-Air Battery Applications

Senthilkumar, Baskar and Irshad, Ahamed and Barpanda, Prabeer (2019) Cobalt and Nickel Phosphates as Multifunctional Air-Cathodes for Rechargeable Hybrid Sodium-Air Battery Applications. In: ACS APPLIED MATERIALS & INTERFACES, 11 (37). pp. 33811-33818.

	PDF acs_app_mat_int_11-37_33811_2019.pdf - Published Version Restricted to Registered users only Download (10MB) | Request a copy
Preview	PDF am9b09090_si_001.pdf - Published Supplemental Material Download (520kB) | Preview

Abstract

Noble-metal-free bifunctional electrocatalysts are indispensable to realize low-cost and energy-efficient rechargeable metal-air batteries. In addition, power density, energy density, and cycle life of these metal-air batteries can be improved further by utilizing the fast faradaic reactions of metal ions in the catalyst layer together with the oxygen evolution/reduction reactions (OER/ORR) for charge storage. In this work, we propose mixed metal phosphates of nickel and cobalt, NixCo3-x(PO4)(2) (x = 0,1, 1.5, 2, and 3), as multifunctional air-cathodes exhibiting bifunctional electrocatalytic activity and reversible metal redox reaction (M3+/2+, M = Ni and Co). Submicron-sized NixCo3-x(PO4)(2) particles were synthesized by a solution combustion synthesis technique with urea acting as the fuel. Electrocatalytic activity toward the oxygen evolution reaction (OER) and oxygen reduction reaction (ORR) in 0.1 M NaOH was systematically tuned by varying the Ni-to-Co ratio. The synthesized NixCo3-x(PO4)(2) with x = 1.5 (NCP11) showed superior bifunctional catalytic activity to other samples. Moreover, the catalyst material delivered a specific capacity of , similar to 110 mAh g(-1) by the redox reactions of its metal sites. The hybrid Na-air battery fabricated using the NCP11 catalyst-loaded aircathode exhibited low overpotential, stable cycling performance, and round-trip energy efficiency exceeding 78% in a 0.1 M NaOH aqueous electrolyte.

Item Type:	Journal Article
Publication:	ACS APPLIED MATERIALS & INTERFACES
Publisher:	AMER CHEMICAL SOC
Additional Information:	copyright for this article belongs to AMER CHEMICAL SOC
Keywords:	nickel-cobalt phosphate; hybrid battery; bifunctional electrocatalyst; Na-air battery; aqueous electrolyte; NASICON; sodium super ionic conductor
Department/Centre:	Division of Chemical Sciences > Materials Research Centre
Date Deposited:	22 Oct 2019 10:12
Last Modified:	22 Oct 2019 10:12
URI:	http://eprints.iisc.ac.in/id/eprint/63780

Actions (login required)

View Item