Highly efficient visible/near-IR-light-driven photocatalytic H-2 production over asymmetric phthalocyanine-sensitized TiO2

Although dye-sensitized semiconductors for photocatalytic H-2 production have been reported for more than 20 years, the spectral response is still focused on the region of 400-600 nm and it is almost never extended to >600 nm. The present work successfully uses zinc phthalocyanine (Zn-tri-PcNc) and naphthalocyanine (Zn-tetra-Nc) to sensitize TiO2 for photocatalytic H-2 production, which expands the spectral response of dye-sensitized semiconductors by harvesting light from 600 to 800 nm. Zn-tri-PcNc/TiO2 has a H-2 production amount of 567.4 mmol with a turnover number (TON) of similar to 7565, which is much higher than that of Zn-tetra-Nc/TiO2 (236.5 mmol H-2 with a TON of similar to 3153). In particular, Zn-tri-PcNc-sensitized TiO2 shows an apparent quantum yield (AQY) of up to 0.2% under 700 nm monochromatic light irradiation and similar to 0.1% under monochromatic light irradiation between 500 and 800 nm, indicating its efficient visible/near-IR-light-driven photocatalytic H-2 production. Future work on the panchromatic responsive dye-sensitized semiconductor system can be carried out using phthalocyanines co-sensitized with other dyes to utilize the whole visible/near-IR light of sunlight.Chemistry, MultidisciplinarySCI(E)9ARTICLE3414363-14370