A special nano-micro hybrid anchored porphyrin metal-organic framework for enhanced photocatalytic hydrogen generation

It is significant to fabricate cheap and active compounds used in energy conversion. Herein, a new nano-micro composite was facilely fabricated by constructing two-dimensional Cu carboxyphenyl porphyrin metal-organic framework (CTMOF) on TiO2 microspheres (TMS). It showed that the light absorption and the transfer of photogenerated charges in TMS could be greatly improved by the introduction of CTMOF. Importantly, the obtained nano-micro composite (TMS/CTMOF) displayed excellent performance in photocatalytic hydrogen production. Under the same condition, its photocatalytic hydrogen evolution (86.11 mmol g−1, 6 h irradiation) was 14.5 times and 21.2 times of pure TMS and CTMOF, respectively, indicating the synergetic effect of TMS and CTMOF. Moreover, after 5 cycles (Every cycle was 6 h), the photocatalytic stability of the nano-micro composite was still greatly higher than those of the pure TMS and CTMOF. Furthermore, photocatalytic mechanism was clarified in order to demonstrate the improved activity in the nano-micro composite. This research will provide new ideas for constructing greatly active composite systems for photocatalytic H2 evolution.