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

Abstract

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.