Ag_(24)Au cluster decorated mesoporous Co_(3)O_(4)for highly selective and efficient photothermal CO_(2)hydrogenation

Photothermal carbon dioxide hydrogenation represents a promising route to reduce the emission of greenhouse gas CO_(2)and produce value-added chemicals,but the selectivity and stability of photothermal catalysts need to be improved.Herein,we report the rational fabrication of well-defined Ag_(24)Au cluster decorated highly ordered nanorod-like mesoporous Co_(3)O_(4)(Ag_(24)Au/mesoCo_(3)O_(4))for highly efficient and selective CO_(2)hydrogenation.The orderly assembled meso-Co_(3)O_(4)nanorods were prepared via a nanocasting method,offering large surface area and abundant active sites for CO_(2)adsorption and conversion.Moreover,the catalytic activity and selectivity were further improved by molecule-like Ag_(24)Au cluster decoration and reaction temperature optimization.The Ag_(24)Au/meso-Co_(3)O_(4)composite catalyst exhibited an ultrahigh CH_(4)yield rate of 204 mmol·g^(−1)·h^(−1)and a greatly improved CH_(4)selectivity of 82%for CO_(2)hydrogenation,significantly higher than those of pristine meso-Co_(3)O_(4)catalyst.The mechanism of the photothermal catalytic performance improvement was verified by CO_(2)temperature-programmed desorption and time-resolved transient photoluminescence,revealing that CO_(2)molecules underwent a vigorous adsorption and rapid activation process over Ag_(24)Au/meso-Co_(3)O_(4).The hot electrons created by the localized surface plasmon resonance effect of Ag_(24)Au clusters facilitated the charge transfer for subsequent multi-electron CO_(2)hydrogeneration processes,resulting in a significant increase in the productivity and selectivity for CO_(2)-to-CH_(4)conversion.This work suggests that the rational coupling of well-defined metal atom clusters and ordered transition metal compound nanostructures could open a new avenue towards photoinduced green chemistry processes for efficient CO_(2)recycling and reutilization.