Toward high-performance dibenzo[g,p]chrysene-based conjugated polymer photocatalysts for photocatalytic hydrogen production through donor-acceptor-acceptor structure design

The exploration on boosting the photocatalytic performance of donor-acceptor (D-A) type polymer photocatalysts is hindered by their fixed chemical compositions. Herein, a series of donor-acceptor-acceptor (D-A-A) type conjugated polymer photocatalysts with tunable components was synthesized through ternary statistical copolymerization by adopting dibenzo[g,p]chrysene and dibenzothiophene-S,S-dioxide as the donor and acceptor, respectively. It reveals that the hydrogen evolution rate (HER) of the resulting copolymers strongly depends on the molar ratio of donor to acceptor. The optimized photocatalyst DBC-BTDO-2 with a molar ratio of 1:3 for donor to acceptor shows an attractive HER of 214.43 mmol h-1 g-1 under UV-vis light without cocatalysts, which is twice as that of its counterpart DBC-BTDO with a D-A structure. Remarkably, DBC-BTDO-2 also realizes an ultra-high HER of 301.92 mmol h-1 g-1 under solar light. These findings highlight the great potential of D-A-A structural design with finely tuned component for boosting the photocatalytic activity of polymer photocatalysts.