Facet Engineering-Induced\nConstruction of Ni₂P/ZnIn₂S₄ Heterostructures\nfor Boosted Photocatalytic\nCO₂ Reduction

Abstract

Facet engineering was realized to enhance the CO₂ photoreduction\nperformance of the Ni₂P/ZnIn₂S₄ heterostructure,\nin which the commonly exposed (1 0 2) face of ZnIn₂S₄ was converted to the (1 0 1) face due to the unique properties\nof the phosphide. The variation in the crystal plane strengthened\nthe intense interfacial contact between Ni₂P and ZnIn₂S₄, resulting in the promotion of utilization and\nabsorption efficiency for incident light and boosting the surface\nreaction rate. Combined with the significant metallicity of Ni₂P, inhibited recombination and strengthened transfer efficiency\nwere achieved, leading to an obvious enhancement of photoreduction\nactivity over Ni₂P/ZnIn₂S₄ compared\nto pure samples. In particular, the optimal NZ7 composite (the mass\nratio of Ni₂P to ZnIn₂S₄) reached\n68.31 μmol h^–1 g^–1 of CH₄, 10.65 μmol h^–1 g^–1 of CH₃OH, and 11.15 μmol h^–1 g^–1 of HCOOH. The mechanism of the CO₂ photoreduction\nprocess was elucidated using ESR and in situ DRIFTS techniques.