Poly(acrylic acid)-modified silica nanoparticles as a nonmetal catalyst for NaBH4 methanolysis

In the present work, a SiO₂@PAA catalyst for NaBH₄ methanolysis composed of silica nanoparticles modified with poly(acrylic acid) has been developed. The morphology and composition of the prepared SiO₂@PAA catalyst were analyzed with transmission electron microscopy, Fourier transform-infrared spectroscopy, x-ray photoelectron spectroscopy and thermogravimetric analysis. This catalyst showed excellent catalytic performance for methanolysis of NaBH₄. The NaBH₄ methanolysis reaction catalyzed by SiO₂@PAA showed an average hydrogen generation rate 5.5 times as high as the reaction catalyzed by unmodified SiO₂ and 10.6 times as high as the uncatalyzed reaction, respectively. The activation energy for methanolysis of NaBH₄ catalyzed by this SiO₂@PAA catalyst was 24.03 kJ/mol. Moreover, although the catalytic activity of SiO₂@PAA catalyst partially lost after being used, it could be restored after being regenerated by washing with diluted hydrochloric acid solution.