The preparation and use of p(2-acrylamido-2-methyl-1-propanesulfonic acid)-tris(dioxa-3,6-heptyl)amine (p(AMPS)-TDA-1) ionic liquid microgel in hydrogen production

Microgels of polymeric ionic liquid (PIL) combine the advantages of the both ionic liquids and polymeric microgels. The microgel in this work was prepared from 2-acrylamido-2-methyl-1-propanesulfonic acid (AMPS) treated with tris(dioxa-3,6-heptyl) amine (TDA-1) (p(AMPS)-TDA-1), synthesized in a water in oil micro-emulsion via photo-irradiation, with a wavelength of 420 nm, for 2 h. The synthesized p(AMPS)-TDA-1 PIL microgels were then characterized via microscope, scanning electron microscope, Fourier transform infrared spectrometer, thermogravimetric analyzer, and zeta potential measurements. Applications of these PIL microgels were also investigated by using p(AMPS)-TDA-1 PIL as a template for in situ Co and Ni metal nanoparticle preparation and as a catalyst in the hydrolysis of NaBH₄ for H₂ production. The potential for p(AMPS)-TDA-1 PIL microgels as metal-free catalyst in the methanolysis of NaBH₄ for H₂ generation was explored as well. It was found that the metal-free p(AMPS)-TDA-1 PIL microgel displayed superior catalytic activity in methanolysis of NaBH₄ reaction with a hydrogen generation rate (HGR) of 854 ± 51.6 mL H₂/(min g of catalyst) and very low activation energy (E_a), 14.3 kJ/mol E_a. Reusability tests on the p(AMPS)-TDA-1 PIL microgel as a metal-free catalysis showed promising results; At end of the 10th trail, no decrease in the 100% conversion was observed with only 14% decrease in activity.