Enhancing the photocatalytic hydrogen production performance of SrTiO3 by coating with a hydrophilic poloxamer

Abstract

Surface modification is a key strategy for promoting the photocatalytic performance of nanoparticles. In this work, triblock copolymer P123 (PEO-PPO-PEO) has been used as a surfactant in the synthesis of SrTiO3. Instead of removing P123 by annealing after the synthesis process, the photocatalytic performance of P123@SrTiO3 heterostructures was evaluated. Compared with SrTiO3, the hydrophilicity of P123@SrTiO3 has been greatly improved. Poly ethylene oxide and its copolymers have excellent affinity for carriers and contribute to carriers transfer. At the same time, the improvement of surface wettability is beneficial to reduce the adsorption energy of water molecules, which speeds up the frequency at which carriers react with water molecules. As a result, photocatalytic hydrogen production of P123@SrTiO3 reaches as high as 402 μmol·g−1·h−1 in the absence of any cocatalyst, which is 31 times that of pure SrTiO3. However, the specific surface area of P123@SrTiO3 is only 5.2 times that of SrTiO3. P123@SrTiO3 retained high catalytic activity after a long reaction. The construction of surface hydrophilic heterojunction provides a new idea for the design of photocatalytic materials.