Photocatalytic synthesis of small-molecule drugs by porous framework materials

The multiple roles of rare earth elements in the field of photocatalysis

“…12–22 The mechanism of the photocatalytic reaction has also been confirmed by scientists: when a beam of light is irradiated on the semiconductor photocatalyst, the energy of the incident light ( hυ ) is higher than the forbidden bandwidth ( E g ) of the semiconductor, the electrons (e − ) in the valence band are excited to transition to the conduction band, and at the same time, the valence band produces holes (h + ), and under the action of the electric field, the e − and h + diffuse to the surface of the catalyst, and the e − and h + are separated efficiently so that the conduction band and the valence band have the capacity to oxidize and reduce, respectively, which can have a redox reaction with the surface adsorption of the material to produce a product in line with the expectation of the people. 23–26 Therefore, photocatalytic reactions are one of the most promising solutions to the environmental and energy crisis through the efficient and rational use of sunlight for redox reactions. However, despite the relatively mature development of photocatalytic technology currently, photocatalysts still commonly encounter many issues, such as insufficient active sites, high photogenerated electron–hole recombination rates, small light absorption ranges, poor product selectivity, etc ., which seriously hinder large-scale practical application of photocatalysts.…”