Construct organic/inorganic heterojunction photocatalyst of benzene-ring-grafted g-C3N4/CdSe for photocatalytic H2 evolution

Photocatalytic water splitting to produce hydrogen is a vital research direction for alleviating the energy crisis. Herein, benzene-ring grafted g-C3N4 nanotubes (Ph-g-C3N4) were prepared skillfully and coupled with CdSe nanoparticles which was realized efficiently hydrogen production. The addition of CdSe nanoparticles enhanced the stability of the catalytic system dispersion in water, and the absorbance of the composites catalyst CdSe/Ph-g-C3N4 (CPG) was enhanced. In addition, the CPG had been characterized to have low resistance and efficient photogenerated electron separation efficiency. The Ph-g-C3N4 nanotubes with a three-dimensional structure can provide an anchoring platform for CdSe nanoparticles and effectively prevent the agglomeration of CdSe. The constructed composites catalyst achieved the efficient transfer of photogenerated electrons as known from photoluminescence spectroscopy test analysis. When CdSe nanoparticles were anchored to Ph-g-C3N4, the electron transfer rate of the constructed composite was about twice that of the Ph-g-C3N4, which facilitates the hydrogen evolution reaction. The character and electron transfer pathways of the photocatalysts were investigated theoretically by performing density functional calculations. The finding provides a new idea for the doping of photocatalysts and the design of organic/inorganic heterojunction composites photocatalyst to achieve an efficient hydrogen production system.