Tetra-armed conjugated microporous polymers for gas adsorption and photocatalytic hydrogen evolution

Two novel tetra-armed conjugated microporous polymers with different geometries have been designed and synthesized via Suzuki-Miyaura cross coupling polycondensation. Both polymers are stable in various organic solvents tested and are thermally stable. The pyrene-containing polymer of PrPy with the rigid pyrene unit shows a higher Brunauer-Emmet-Teller specific surface area of 1219 m2 g−1 than the tetraphenylethylene-containing polymer of PrTPE (770 m2 g−1), which leads to a high CO2 uptake ability of 3.89 mmol g−1 at 1.13 bar/273 K and a H2 uptake ability of 1.69 wt% at 1.13 bar/77 K. The photocatalytic hydrogen production experiments revealed that PrPy also shows a better photocatalytic performance than PrTPE due to the higher conjugation degree and planar structure, the broader UV-visible (UV-Vis) absorption, the lower photoluminescence lifetime, and the higher specific surface area.