In Situ Reconstruction of a Highly Integrated Cu/Cu ₂ O/MoO ₂ Dual Heterojunctions for High‐Performance CO ₂ Photothermal Catalysis

Abstract

ABSTRACT During heterogeneous photothermal catalysis, catalysts are prone to undergo random and disordered structural evolution, which poses a severe challenge to the construction of advanced photothermal catalytic systems integrating photoexcited charge carrier separation, molecular activation, and active‐site engineering. In this work, we employ an in situ reconstruction strategy to fabricate a highly integrated Cu/Cu 2 O/MoO 2 composite catalyst using Cu 3 Mo 2 O 9 as the precursor under a CO 2 /H 2 reaction atmosphere. The as‐constructed Cu/Cu 2 O Schottky junction and Cu 2 O/MoO 2 p‐n junction form a dual‐heterojunction structure, enabling efficient separation of photogenerated charge carriers. Meanwhile, amorphous MoO 2 with abundant oxygen vacancies and Cu/Cu 2 O provide functionally complementary activation sites for CO 2 activation and H 2 dissociation/spillover, respectively. Benefiting from the efficient synergistic interplay among the three components (Cu, Cu 2 O, and MoO 2 ), the Cu/Cu 2 O/MoO 2 catalyst enables the efficient conversion of CO 2 via the photothermal reverse water‐gas shift (RWGS) reaction, delivering a superior CO production rate of 14.65 mmol g −1  h −1 alongside ultra‐long stability, retaining high activity across an impressive 215‐h continuous reaction run. This study offers a new avenue for the construction of integrated functional photothermal catalysts with high performance via an in situ reconstruction approach.