Synergistic Effect of Oxygen Vacancy-Rich SnO₂ and AgCl in the Augmentation of Sustained Oxygen Reduction Reaction

Abstract

Developing a stable and methanol-tolerant electrocatalyst for a sustained oxygen reduction reaction (ORR) is of great importance for advancing direct methanol fuel cell applications. The silver-based electrocatalysts are particularly interesting among the promising non-Pt-based electrocatalysts for ORR. Herein, we report a single-step synthesis of a composite of AgCl and SnO2 with oxygen vacancy (AgCl–SnO2(VO)), which exhibits sustained and selective catalytic activity for the ORR along with excellent durability. Hydrothermal synthesis generates oxygen vacancies within the material and facilitates a strong interaction between AgCl and SnO2(VO), which effectively augments the ORR activity and the long-term stability of the composite. The composite exhibits remarkable methanol tolerance, as evidenced by a meager shift of only 0.002 V in the half-wave potential. Furthermore, the composite demonstrates excellent durability, with no noticeable changes in onset and half-wave potential even after 2500 cycles. The cost-effectiveness, durability, and ORR selectivity of this composite hold great promise toward contributing to the advancement of clean energy technology.

Ozone-Assisted Hydrothermal Synthesis Method of Sb-Doped SnO2 Conductive Nanoparticles for Carbon-Free Oxygen-Reduction-Reaction Catalysts of Proton-Exchange-Membrane Hydrogen Fuel Cells

“…There are multiple reports about synthesis methods of SnO 2 as Pt (or another catalyst) supports for PEMFCs: sol-gel (including precipitation) methods with annealing [17][18][19][20][21][22][23][24][25][26][27], polyol crystallization without annealing [28], hydrothermal synthesis with annealing [29] and without annealing [30,31], flame oxide-forming [32][33][34][35][36][37][38][39][40][41][42][43][44], electrospinning with annealing [45,46], and atomic layer deposition (ALD) [47]. There is also the problem of additives, such as surfactants, which can cause contamination.…”