Calcination temperature of the perovskite parent compound controls active metal exsolution and catalytic performance for ethanol steam reforming

Abstract

The imperative need for sustainable hydrogen (H2) production has driven increasing research into efficient ethanol steam reforming (ESR) catalysts. This study demonstrates that the calcination temperature of La0.4Sr0.4Ti0.8Ni0.2O3-δ (LSTN) controls surface area, directly influencing both the nickel reducibility and the formation of exsolved Ni0 nanoparticles (5–15 nm). Such parameters result in microstructural properties determining the catalytic performance. ESR catalytic tests at 600 °C, showed that samples calcined at lower temperature (650 °C) achieved complete ethanol conversion and stable H2 yield (4.04 mol mol ethanol−1), whereas increasing calcination temperatures (800 and 1200 °C) significantly reduced surface area and altered product distribution, favoring ethanol dehydrogenation over reforming. The robust properties of exsolved catalysts were demonstrated by ESR stability test that revealed sustained H2 production despite partial deactivation. The experimental results evidenced that controlling the calcination temperature of the parent LSTN oxide before exsolution is a practical parameter for tuning Ni exsolution and catalytic performance, to establish LSTN as a highly effective and stable material for renewable H2 production via ESR. © 2025 Hydrogen Energy Publications LLC.