Gold incorporated hematite nanocatalyst for solvent-free CO2 fixation under atmospheric pressure

Abstract

We have developed an efficient one-pot synthesis strategy for the preparation of hematite (α-Fe₂O₃) and gold-integrated hematite (Au/α-Fe₂O₃) nanocatalysts. The nanostructured hematite along with tetrabutylammonium iodide (TBAI) has emerged as a proficient catalyst-combination for the reaction between carbon dioxide (CO₂) and epoxide to form cyclic carbonate with 77% conversion under atmospheric CO₂ pressure and solvent-free conditions. The catalytic activity of hematite further improved on the incorporation of a miniscule amount of gold (Au) into the hematite system. The as-prepared Au/α-Fe₂O₃ nanocatalyst with TBAI is found to be very efficient for the CO₂ fixation reaction with 91% conversion under the optimized reaction conditions. The excellent catalytic activity of Au/α-Fe₂O₃ is attributed to the synergistic effect between α-Fe₂O₃ and Au species for the efficient fixation of CO₂. Furthermore, the recyclability and post catalytic analysis imply the robust nature of the heterogeneous Au/α-Fe₂O₃ nanocatalyst.