Dithiocarbamate-Linked Phthalocyanine with CdSe QDs Enhancing Charge Transfer for Selective Photocatalytic CO2 Reduction

Photocatalytic CO2 reduction (PCR) to chemical fuels represents a promising solution to the energy crisis and global warming. The rational design of efficient photocatalysts is key to PCR. In this study, a molecular heterogeneous photocatalyst is constructed with cobalt (II) 2,9,16,23-tetraaminophthalocyanine (CoPc-NH2) covalently linked to CdSe quantum dots (QDs) via a dithiocarbamate group (& horbar;NHCS2). This covalent bond (& horbar;NHCS2) enables directional, efficient, and fast interfacial electron transfer, substantially improving the catalytic activity. The optimized CdSe@CoPc-NH2 heterojunction exhibits excellent activity for CO2 reduction, achieving an average CO generation rate of 3, 687 mu mol g(-1) h(-1) (TONCO = 2, 360), which is 31 times higher than that of pristine CdSe QDs. Furthermore, immobilizing CoPc-NH2 on CdSe QDs increases the selectivity for CO from 20% to 90%. The in situ formation of molecular heterogeneous photocatalysts features a covalently bonded interface, which can offer valuable insights for designing efficient photocatalysts for solar fuel generation.