Construction of dual Z-scheme heterostructure TCN/In2O3/ZnO composite with oxygen vacancies for enhanced artificial nitrogen fixation

The synergistic effect between vacancy engineering and heterostructures can effectively improve the interfacial charge transfer ability and efficiency of catalytic nitrogen reduction. Herein, a ternary dual Z-scheme tubular carbon nitride composited oxygen vacancy-induced indium oxide and oxygen vacancy-induced zinc oxide catalyst (TCN/Vo-In₂O₃/Vo-ZnO) was constructed, and the synergistic mechanism of charge transport at the catalyst interface was explored. The excellent efficiency of nitrogen fixation could reach 171.56 μmol/L within 120 min, and the high stability of TCN/Vo-In₂O₃/Vo-ZnO was favorable for practical applications. All experiments indicated that the dual-Z scheme heterostructure and oxygen vacancies have a synergistic effect. Oxygen vacancies could control the valence band position. This control improved the transfer rate of photogenerated charge carriers between heterojunctions, thereby enhancing the adsorption and activation of N₂. This study may offer new insights into the synthesis of highly efficient catalysts for photocatalytic nitrogen fixation.