Enhanced photocatalytic H2/H2O2 production and tetracycline degradation performance of CdSe quantum dots supported on K, P, N-co-doped hollow carbon polyhedrons

[Display omitted] •K, P, N-co-doped hollow carbon polyhedron (KPN-HCP) was used to support CdSe QDs.•KPN-HCP was obtained by carbonization of PPh3@ZIF-8 and recalcination in LiCl-KCl.•Light response, electrons transfer from CdSe to HCP increase after K, P, N-doping.•H2/H2O2 evolution and TC degradation ratio of CdSe/KPN-HCP were largely increased. A K, P, N-co-doped hollow carbon polyhedron (KPN-HCP) was prepared by two-step calcination of triphenylphosphine@ZIF-8, which was then used to modify CdSe quantum dots (QDs). The effect of the dopants on the photocatalytic activity of CdSe QDs for H2/H2O2 production and tetracycline degradation was investigated. Through post-calcination in KCl-LiCl, the hollow polyhedron morphology was retained in KPN-HCP, and the graphitization degree increased. The introduction of P atoms followed by K+ doping could significantly enhance light harvesting, and accelerate electrons transfer from CdSe QDs to HCP. The H2 evolution rate and apparent rate constant of TC degradation for CdSe/KPN-HCP were 39.9- and 7.5-fold larger than those for CdSe QDs, respectively. The yield of H2O2 for CdSe/KPN-HCP in water was 900.0 μmol g−1 after 60 min. This work provides new insights for design of QD-based photocatalysts with high photocatalytic H2/H2O2 evolution, and tetracycline degradation activity.