Atomically Dispersed Praseodymium-Modified Ni Active Sites Boost the Direct Cleavage of Carbonate Intermediates for Photothermal CO2 Conversion.

Abstract

Photothermal catalytic reduction of carbon dioxide (CO2) into valuable chemical feedstocks represents a sustainable approach for storing intermittent renewable energy and reducing CO2 emissions. However, this process is still impeded by the inherent inertness of CO2 and the production of multiple intermediates. Herein, we propose a strategy that facilitates the direct cleavage of carbonate intermediates to boost photothermal catalytic CO2 conversion. A highly efficient catalyst featuring active sites designed to improve the carbonate coverage was successfully constructed, composed of atomically dispersed praseodymium-modified ceria loaded with highly dispersed nickel species (Ni/Pr-CeO2). The fine structure of the prepared catalysts was revealed by high-resolution, high-angle annular dark-field scanning transmission electron microscopy, and X-ray absorption fine structure. Multiple in situ/operando spectroscopy techniques confirmed the active participation of interface oxygen species from Ni/Pr-CeO2 in enhancing carbonate (CO3*) and bicarbonate (HCO3*) intermediates coverage and transformation. In particular, under light irradiation, the C═O bonds within these intermediates are effectively weakened and cleaved, overcoming the high energy barrier associated with CO2 activation and enabling efficient CO production. As a result, the Ni/Pr-CeO2 catalyst demonstrates a high CO yield of 27.2 mol molNi-1 min-1, which is nearly three times higher than that of the Ni/CeO2 catalyst and maintains exceptional stability over 110 h without deactivation. Our findings contribute to the development of efficient catalytic systems that not only recycle greenhouse gases but also facilitate the integration of intermittent renewable energy sources into the chemical production landscape.