Anti-defect engineering of Pd/NiCo2O4 hybrid nanocatalysts for enhanced CO2 hydrogenation to formate

Abstract

Efficiently converting CO₂ into value-added chemicals remains a significant challenge due to its inert nature. Here, we present the rational design of Pd/NiCo₂O₄ hybrid nanocatalysts with diverse morphologies for highly efficient CO₂ hydrogenation to formate. The synergistic combination of Pd and NiCo₂O₄ offers improved catalytic activity towards formate production. Remarkably, the observation of a morphology-dependent Pd-NiCo₂O₄ interaction, linked to the presence of oxygen vacancies in NiCo₂O₄, significantly contributes to our understanding of catalytic activity. The rose-like Pd/NiCo₂O₄ catalyst achieves an impressive formate yield (85.3 mol_formate mol_totalPd⁻¹ h⁻¹) due to its low oxygen vacancy concentration and subsequent generation of less positively-charged Pd species, emphasizing the crucial role of oxygen vacancies in hybrid nanocatalyst performance. These findings were further validated through density functional theory calculations, providing valuable insights into the design and optimization of nanocatalysts for CO₂ hydrogenation. This contributes to the development of efficient and sustainable processes for CO₂ utilization in the production of formate and other valuable chemicals.