PI Session 2, PI Session
PI2-012

Highly defective perovskite-based catalysts for energy and environment: application in methanol synthesis from CO2 hydrogenation

C. Pischetola1, L. Artiglia1, A. Bugaev1, F. Talebkeikhah1, F. Yao1, V. Sushkevich1, M. Vanni1, F. Krumeich1, J. van Bokhoven1,2
1Paul Scherrer Institute, Forschungsstrasse 111, 5232, Villigen, Switzerland, 2ETH Zurich, Institute for Chemical and Bioengineering, Vladimir-Prelog-Weg 1, 8093, Zurich, Switzerland

Within the energy and environment sector, perovskites are materials immediately associated to photoand electro-catalytic applications, while largely overlooked by the thermocatalysis community due to their small surface area (<10 m2 g-1), despite exceptional structural and electronical tunability [1]. The formation of oxygen vacancies (Ov) from catalyst’s partial reduction has proven to be key for the selective production of methanol (MeOH) from carbon dioxide (CO2) [2]. Given the environmental relevance of CO2 valorisation into chemicals, finding efficient strategies to optimise the content of Ov on the catalyst surface is pivotal. My research identifies perovskite SrTiO3 as a next-generation methanol catalyst (see Figure 1). Materials engineering delivered high surface areas SrTiO3 support (I) with dispersed copper nanoparticles by deposition (Cu/STO, (II)) and from exsolution (SCTO, (III)). From catalytic tests under relevant energysaving conditions, a MeOH selectivity over 96% and STY (molMeOH mol-1 Cu h-1) outmatching that from standard catalyst (CZA) were obtained (IV-V). In-situ/operando tools (XPS, XRD, XAS, FTIR) unveiled the nature of the catalytic sites: coupled Cu + Ov (at the interphase or as isolated clusters). These are dynamic systems whose content is affected by the environment (gas, temperature and pressure) at which the catalyst is exposed (Vi-VII). A direct correlation between the concentration of formate surface intermediate and content of Ov was established (VIII). Our results show the potentiality of the newly developed catalysts.

Figure 1. Characterisation and catalytic data from Cu/STO and SCTO materials. (I) N2 Physisorption and BET data; (II) TEM and (III) EDX images;(IV) MeOH selectivity and (V) STY from catalytic data; Operando XAS data over (VI) Cu K-edge and (VII) Ti K-edge; (VII) Formate intensity from operando IR with O 1s from XPS as inset, where the red area component refers to the oxygens close to a Ov.

[1] J. Mi et al, Chem. Eur. J., 2023, 29, e202202713.
[2] C. Pischetola et al., Catal. Sci. Technol., 2025, 15, 2722.