Oxygen vacancy-rich In2O3-ZrO2 catalysts synthesized via DBD plasma for enhanced CO2-to-CO conversion

Abstract

The efficient utilization of CO₂ as a carbon feedstock is vital for achieving carbon neutrality while enabling sustainable production of C₁ chemicals. Plasma-assisted catalytic conversion has emerged as a promising strategy under mild conditions, yet its progress is limited by the lack of highly active and plasma-tolerant catalysts. In this work, an In₂O₃-ZrO₂ composite catalyst with high catalytic activity, excellent thermal stability and long service life was successfully prepared by combining the chemical precipitation method with plasma technology. The In-Zr (1 : 1) catalyst exhibited the best performance, reaching a CO₂ conversion of 26.3% and CO selectivity above 90% at an SIE of 104 kJ L⁻¹. Compared with pure In₂O₃, the composite showed markedly improved thermal stability, sustaining continuous operation for 450 min, three times longer than In₂O₃. Plasma modification induced a higher concentration of oxygen vacancies (1.69 × 10¹³ spins per g), increased surface area (56.7 m² g⁻¹), and a narrowed bandgap (2.49 eV), which synergistically enhanced catalytic activity. Mechanistic studies and DFT calculations further revealed that the strong plasma-catalyst interaction facilitates CO₂ activation pathways. This study demonstrates not only the durability of In-Zr composites but also highlights plasma modification as an effective strategy to design next-generation catalysts for plasma-assisted CO₂ utilization. Meanwhile, the In-Zr catalyst successfully developed in this study, with its outstanding performance, stability and durability, is a highly promising candidate material for high-temperature industrial catalytic processes.