Dual-functional (NiPS3 NSs + BP QDs)@In2O3 heterojunction for synergistic photocatalytic degradation of antibiotics and hydrogen evolution

The elimination of emerging organic contaminants and the exploitation of clean hydrogen energy are critical research topics in environmental remediation. Indium oxide (In 2 O 3 ) serves as a promising dual-functional photocatalyst with low resistivity and high catalytic activity, yet bare In 2 O 3 suffers severe recombination of photogenerated carriers to limit its practical performance. In this study, a ternary composite photocatalyst, (NiPS 3 NSs + BP QDs)@In 2 O 3 , was successfully constructed by co-modifying In 2 O 3 with two-dimensional NiPS 3 nanosheets and zero-dimensional black phosphorus quantum dots (BP QDs). A full set of characterizations delivers solid evidence for the formation of multi-component heterostructures. Photocatalytic tests confirm the composite strengthens visible-light absorption and accelerates carrier separation efficiency. Regarding degradation performance, (NiPS 3 NSs(20%) + BP QDs(4%))@In 2 O 3 exhibited optimal activity: the degradation rates of sulfamethoxazole, ampicillin, and ofloxacin reached 93.8% within 60 min, 96.9% within 70 min, and 94.4% within 90 min, respectively. Regarding hydrogen evolution performance, (NiPS 3 NSs(5%) + BP QDs(4%))@In 2 O 3 displayed the highest activity. A noticeable mismatch exists between the optimal cocatalyst dosages for degradation and hydrogen evolution, which reflects distinct functional demands of the two reactions. Mott–Schottky and VB-XPS results indicate fast interfacial charge transfer, and flat-band derived band alignment diagrams are supplied to clarify carrier migration routes.