Hollow spherical Cu/CuO-Fe3O4 composite for high-efficiency photothermal co-catalysis of hydrogen evolution

Abstract

Harnessing the full solar spectrum through photothermal co-catalysis represents a transformative approach for optimizing energyconversion and advancing sustainable development. Herein, a hollow spherical Cu/CuO-Fe3O4 composite was developed as a photothermal cocatalyst for efficient hydrogen evolution. The unique hollow spherical architecture significantly enhances solar light harvesting, reduces thermal dissipation, and provides an ideal confined environment for catalytic reactions. Metallic Cu serving as the primary contributor to the LSPR effect, enabling effective light harvesting and photothermal conversion. Meanwhile, CuO, as a semiconducting oxide, contributes to charge separation and transfer, working synergistically with Fe3O4. A robust heterojunction interface between Cu, CuO, and Fe3O4 ensures efficient separation and migration of photogenerated charge carriers. This synergy, combining the LSPR effect of Cu, the photothermal properties of Fe3O4, and the catalytic functionality of CuO, results in significantly enhanced hydrogen evolution activity. Operated under an oxygen-mediated mechanism, the catalyst achieved an impressive hydrogen evolution rate of 13,371.36 μmol·gcatalyst-1·h-1 at a partial oxygen pressure of 1.0 atm. These findings underscore the potential of hollow spherical Cu/CuO-Fe3O4 composites as advanced photothermal co-catalysis as a viable pathway for next-generation clean energy applications.