Waste biomass-assisted synthesis of TiO2 and N/O-contained graphene-like biochar composites for enhanced adsorptive and photocatalytic performances

•The biochar/TiO2 composite was prepared by facile biomass-assisted pyrolysis and activation strategies.•Better photocatalytic activity than pure TiO2 and commercial graphite/TiO2 composite.•The interaction between TiO2 and biochar influences the photocatalytic performance.•The method is simple, cheap, and environmental. Titanium dioxide (TiO2) is a promising semiconductor photocatalyst for degradation of organic pollutants but is hampered by bandwidth prohibition and high probability of photo-generated electron-hole recombination. Searching for effective modification strategies to alleviate these issues is thus particularly significant. Herein, two series of composites of TiO2 and graphene-like biochar (PC) were prepared via a simple biomass-assisted pyrolysis coupled with activation strategy and characterized by various techniques. The methylene blue (MB)-simulated waste water was used to evaluate their adsorptive and photocatalytic performances. The results showed that the optimal TiO2-PC composite delivered an excellent photocatalytic performance, nearly 4 times as TiO2. The enhanced performance was probably caused by the synergistic effect among the graphene-like PC, the self-introduced N/O heteroatom, and the interaction between TiO2 and PC. Furthermore, the possible photocatalytic process was also proposed. This work may provide a guidance on preparing high-performance composites through a simple, cheap, and environmental biomass-assisted strategy for highly-efficient photocatalysis application.