ISSN print edition: 0366-6352 ISSN electronic edition: 1336-9075 Registr. No.: MK SR 9/7 Published monthly

Hydrothermally synthesized mixed phase of Ni₃S₄/NiS₂ as an efficient electrode for electrochemical devices

Rekha Bhardwaj, Vanita Bhardwaj, and Ranjana Jha

Department of Applied Sciences, Bharati Vidyapeeth’s College of Engineering, New Delhi, India

E-mail: rekhabhardwaj488@gmail.com

Received: 13 June 2025  Accepted: 14 August 2025

Abstract:

In this study, composite of Ni₃S₄/NiS₂ was synthesized using single-step hydrothermal route. A series of characterization like X-ray diffraction and Fourier transform infrared confirms the formation of heterostructure nickel sulfide which consists of NiS₂ and Ni₃S₄ phase. Characteristics of mixed phase of Ni₃S₄/NiS₂ relationship have been examined by electrochemical test. Charge transfer resistance of the synthesized composite Ni₃S₄/NiS₂ is 15.79 \(\Omega\). Areal and specific capacitance of prepared composite is 4.96 F/cm² and 545 F/g at 3 mV/s, respectively, and it shows 89% cyclic stability over 1600 cycle at constant scan rate of 50 mV/s. 1 M LiOH aqueous solution used as electrolyte during the characterization of electrochemical test. Surface property of composite Ni₃S₄/NiS₂ has been examined by nitrogen isotherm, and pore size of the composite is 3.934 nm which provides the effective path for electron transportation between the surface of working electrode and electrolyte. The calculated parameters of the series of characterization indicated that prepared composite of Ni₃S₄/NiS₂ is a potential electrode material for electrochemical devices.

Keywords: Cyclic stability; Composite Ni3S4/NiS2; Pore diameter; Charge transfer resistance

Full paper is available at www.springerlink.com.

DOI: 10.1007/s11696-025-04334-8

Chemical Papers 79 (12) 8549–8560 (2025)