Phosphorus decorated g-C3N4-TiO2 particles as efficient metal-free catalysts for hydrogen release by NaBH4 methanolysis

The heterojunction catalyst preparation used in the field of catalytic reaction has a better catalytic effect compared to single-component catalysts. Here, a three-step graphite carbon nitride (g-C3N4), titania(TiO2), and phosphorus(P)-component metal-free catalysts were synthesized. The first step includes the synthesis of g-C3N4 by calcination, the second step includes the synthesis of g-C3N4-TiO2 by calcination, and the third step includes the hydrothermally P doping to the obtained g-C3N4-TiO2 material. The obtained g-C3N4-TiO2-P catalyst was used for the first time in the efficient hydrogen (H-2) release from the sodium borohydride (NaBH4) methanolysis. The structural properties of these metal-free catalysts were performed by XRD, FTIR, SEM-EDS and XPS analyses. NaBH4 concentration effect, catalyst amounts effect, temperature effect and reusability experiments were carried out. An HGR value of 14750 mL min(-1)g(-1) was obtained with 2.5% NaBH4 using 10 mg of catalyst. The activation energy (Ea) for the g-C3N4-TiO2-P catalyst was 36.17 kJ mol(-1). Also, the mechanism of the H-2 production reaction from this NaBH4 methanolysis of g-C3N4-TiO2-P catalyst was tried to be explained.