Work

Effect of Ni-Doping in LaCo 1– x Ni x O 3 on Electrocatalytic Oxygen Reduction Reaction

Year: 2025

Type: article

Abstract: High Resolution Image Download MS PowerPoint Slide Methanol crossover severely limits the performance of direct methanol fuel cells (DMFCs) by introducing methanol to the cathode compartment, where it competes with the oxygen reduction reaction (ORR) and poisons platinum-based ORR electrocatalysts, making it essential to develop methanol-tolerant ORR electrocatalysts. Here, Ni doping is explored as a means of improving the electrocatalytic activity and methanol tolerance of LaCo 1– x Ni x O 3 ( x = 0, 0.1, 0.15, and 0.2) perovskite oxide electrocatalysts synthesized using a simple sol–gel method. X-ray diffraction (XRD), Fourier transform infrared (FTIR), X-ray photoelectron spectroscopy (XPS), and energy-dispersive X-ray (EDAX) analysis confirm the formation of LaCoO 3 and successful Ni doping at the Co site. Field-emission scanning electron microscopy (FE-SEM) analysis reveals that the particle size of the synthesized nanoparticles slightly increases upon Ni doping. Although a corresponding decrease in Brunauer–Emmett–Teller (BET) surface area with increasing Ni doping is also found, LaCo 0.8 Ni 0.2 O 3 possesses the highest pore volume and pore radius among all the synthesized perovskite oxides. This optimized composition exhibits superior ORR catalytic activity (0.724 and 0.678 V vs reversible hydrogen electrode (RHE) at current densities of −0.1 and −0.3 mA cm –2, respectively) comparable to Pt/C (0.758 and 0.709 V vs RHE) derived from the linear sweep voltammetry (LSV) study performed at 1600 rpm. In the presence of methanol, all the synthesized perovskite oxides experienced a small negative potential shift (0 to 14 mV) during ORR, suggesting these materials can be used as methanol-tolerant ORR electrocatalysts in DMFCs.

Source: ACS Omega

DOI: 10.1021/acsomega.5c05357

Authors: Shaikh Parwaiz, Fazlurrahman Khan, James Robert Jennings, Mohammad Hilni Harunsani, Young-Mog Kim, Mohammad Mansoob Khan

Institutions: Universiti Brunei Darussalam, Pukyong National University

Language: English

Topic: Electrocatalysts for Energy Conversion

Subfield: Renewable Energy, Sustainability and the Environment

Field: Energy

Domain: Physical Sciences

SDG: Affordable and clean energy

Open Access status: gold

Estimated APC paid: $1,935