Structure-performance relationship of SrTiO₃/S@g-C₃N₄ nanocomposites for highly active hydrogen production via NaBH₄ methanolysis

The catalytic performance of SrTiO₃/S@g-C₃N₄ nanocomposite catalyst for hydrogen production from NaBH₄ methanolysis was investigated. The X-ray diffraction (XRD), attenuated total reflectance (ATR) spectroscopy, and scanning electron microscopy (SEM) analyses revealed the structure of the nanocomposite catalyst. The XRD spectrum of SrTiO₃/S@g-C₃N₄ showed the presence of both SrTiO₃ and S@g-C₃N₄ phases. ATR spectroscopy analysis proved the interaction between SrTiO₃ and g-C₃N₄ that facilitates electron-hole separation and charge transfer. The SEM images demonstrated that the SrTiO₃/S@g-C₃N₄ sheets were broken up during growth. The surface area of SrTiO₃/S@g-C₃N₄ was 195 m²/g, which is higher than that of pristine S@g-C₃N₄ (40 m²/g), while the BJH pore size of SrTiO₃/S@g-C₃N₄ (1.6 nm) was lower than that of S@g-C₃N₄ (2.0 nm). The band gap of the nanocomposite catalyst was reduced from 2.71 to 2.67 eV after the incorporation of SrTiO₃. The PL spectra showed a characteristic peak of S@g-C₃N₄ at 457 nm, which red-shifted with the addition of SrTiO₃. The catalyst SrTiO₃/S@g-C₃N₄ achieved a promising hydrogen production rate of 8537 mL/g.min and a reaction activation energy of 19.20 kJ/mol. These findings show promise for catalytic performance and high efficiency in hydrogen generation from NaBH₄ methanolysis.