Title: Effect of the crystalline phase on the electrocatalytic performance of Sm2-xSrx NiO4-δ (x = 0.4 to 1.0) Ruddlesden Popper based system: A comparison of bulk and thin electrocatalysts

Abstract

Here, we are investigating the effect of composition on the Oxygen Evolution Reaction (OER) mechanism of Sm2- xSrxNiO4-δ (x = 0.4 to 1.0 with a step of 0.2) synthesized through the standard solid-state technique. With the change in oxygen non stoichiometry, Rietveld refinement of X-ray diffractograms and EDX indicate the compositional phase change from orthorhombic to tetragonal. x = 0.6 and 1.0 thin films were also produced using the Pulsed laser deposition technology (PLD) for comparative electrocatalytic behaviour understanding, and cyclic voltammograms were compared to bulk ones to estimate the transient response and electrochemical reversibility. The cyclic voltammetric curves in bulk samples indicate a change in the number of electron transfers with x, as well as a change in electrochemical reversibility. Our findings show that electrochemical reversibility in thin films is driven by adsorption rather than diffusion, as it is in bulk samples. In both bulk and thin films, we found that the tetragonal phase (x= 1.0) has a larger Tafel slope than the orthorhombic phase (x = 0.6).

Biography

Manisha Chauhan is a senior research fellow at the Indian Institute of Technology (BHU), working under Prof. Prabhakar Singh's supervision in the department of physics. Functional materials for energy application, fuel cells, and electrochemical energy devices are my areas of interest. She is currently working on Investigation of Nickelate-based Ruddlesden popper perovskites for fuel cell applications. She has published a couple of papers in prominent journals that look into the catalytic characteristics of the RP system and double perovskite system. And a few papers are in the process of being communicated.