Enhanced photocatalytic overall water splitting from an assembly of donor-π-acceptor conjugated polymeric carbon nitride.

ABSTRACT

Well-organized water splitting semiconducting photocatalyst is an important concept, but stimulating aimed at decisive energy and environmental emergencies. In this context, visible light-based photocatalytic water splitting with low-dimensional semiconducting materials is proposed to produce sustainable energy. Here we optimized the sequential of organic electron-rich heterocyclic monomer namely benzothiadiazole (BTD) quenched within polymeric carbon nitride (PCN) semiconductor via copolymerization, thereby assembling a sanctum of donor-π-acceptor (D-π-A) photocatalysts. The selection of BTD is based on the benzene ring, which consequently anticipating a π cross-linker unit for hydrogen and oxygen evolution. A hydrogen evolution rates (HER) of 88.2 µmol/h for pristine PCN and 744.2 µmol/h for PCN-BTD008 (eight times higher than pure PCN) are observed. Additionally, a remarkable apparent quantum yield (AQY) of about 58.6% at 420 nm has been observed for PCN-BTD008. Likewise, the oxygen evolution rate (OER) data reflect the generation of 0.2 µmol/h1 (visible) and 1.6 µmol/h1 (non-visible) for pure PCN. Though, OER of PCN-BTD008 is found to be 2.2 µmol/h1 (visible) and 14.8 µmol/h1 (non-visible), which are economically better than pure PCN. As such, the results show an important step toward modifying the design and explain a vital part of the D-π-A scheme at a balanced theme for fruitful photocatalysts intended for future demand.