Gelatin-assisted sol–gel derived TiO2 microspheres for hydrogen storage

• This work studied gelatin-aids fabrication for TiO2 mesoporous microspheres.
• These microspheres exhibit large surface area and small pore size.
• The gelatin favors and improves the hydrogen storage of TiO2 microspheres.

TiO2 is an important photocatalyst candidate for solar energy or hydrogen energy harvesting. Creation of porous structures or high surface area within TiO2 microspheres may potentially address the challenge to improve their efficiency. In present work, we report the sol–gel fabrication of mesoporous TiO2 microspheres that assembled from nanoparticles with the assistance of gelatin template. The phase structure, morphology, and mesoporous characteristics were analyzed by X-ray diffraction, transmission electron microscopy, and BET measurements. Particularly, the gelatin-assisted fabricated TiO2 nanoparticles (∼10–20 nm) were achieved to assemble TiO2 microspheres with diameters of 0.2–0.5 μm, which yielded a typical type-IV BET isotherm curve (N2 hysteresis loop) with a large surface area of 98.3 m2/g and a small pore size of 11.9 nm. A simplified model was proposed to investigate the effect mechanism of gelatin on the formation of TiO2 mesoporous microspheres. The room temperature pressure-dependent hydrogen evolution of the gelatin-assisted fabricated TiO2 nanostructures has also been investigated, suggesting that gelatin favors high surface area and improves the hydrogen storage performance, and the achieved TiO2 microspheres could be potential candidates to be utilized as the photocatalyst for hydrogen evolution.