Hybrid Pd₅₀-Ru₅₀/MXene (Ti₃C₂T_x) nanocatalyst for effective hydrogenation of CO₂ to methanol toward climate change control

Increase in atmospheric carbon dioxide (CO₂) concentration has motivated researchers to develop large-scale CO₂ sequestration and subsequent fuel conversion processes using various nanocatalysts. Herein, a 2D alloyed Pd₅₀-Ru₅₀ nanoparticles decorated MXene (Pd₅₀-Ru₅₀/MXene) nanocatalyst for efficient hydrogenation of CO₂ into selective production of methanol is successfully fabricated and analyzed for its performance. HR-TEM and BET studies showed that hexagonal close-packed Pd₅₀-Ru₅₀ was formed with an average size of 3.2 nm and grown on the MXene nanosheets resulting in a higher specific surface area of 120 m² g⁻¹. Among the various catalysts studied, Pd₅₀-Ru₅₀/MXene showed a superior catalytic activity for hydrogenation of CO₂ into selective production of CH₃OH. The CO₂ hydrogenation process involved the hydrolysis of NaBH₄ (H₂ facilitator) with ethylene glycol as CO₂ capture agent. The Pd₅₀-Ru₅₀/MXene catalyst produced a higher CO₂ conversion efficiency of 78% with a CH₃OH yield of 76% (total turnover number based on Pd₅₀-Ru₅₀ = 2932) under mild conditions (pCO₂ = 10 bar; T = 150 °C; t = 12 h). The recyclability test and morphological analysis of the spent Pd₅₀-Ru₅₀/MXene catalyst demonstrated its chemical stability even after prolonged usage for several hours indicating its promise for commercial-scale CO2 capture and renewable liquid fuel production.