P(AAGA) hydrogel reactor for in situ Co and Ni nanoparticle preparation and use in hydrogen generation from the hydrolysis of sodium borohydride

Abstract

A hydrogel prepared from 2-acrylamidoglycolic acid monohydrate (AAGA), denoted by p(AAGA), was used for Co and Ni nanoparticle preparation within the hydrogel matrix. The p(AAGA)–M (M: Co, Ni) composite system was also shown to be capable of carrying out an aqueous reaction effectively, i.e., the hydrolysis of NaBH4 for hydrogen generation. The reaction kinetics are investigated under different reaction conditions and various parameters, such as initial NaBH4 concentration, temperature, catalyst amounts and types, affecting the hydrolysis process of NaBH4 were evaluated. The activation energies for the hydrolysis of NaBH4 were calculated to be 43.77kJmol−1 and 26.62kJmol−1for p(AAGA)–Ni and p(AAGA)–Co catalyst systems, respectively. Even after seven repetitive uses p(AAGA)–Co composite catalyst system had 100% conversion with 95% activity. More importantly, the p(AAGA)–Co system has proven to have very good storage capacity, e.g., after 30-day storage time, p(AAGA)–Co had no loss in conversion and had 68% catalytic activity.