With the limited supply of fossil fuels becoming more of a concern, there has been an increased focus in finding alternative sources of energy. One source of clean energy is hydrogen gas. Studies have been done examining the generation of hydrogen gas from water, which is an energy intensive process. There has been less effort in generating hydrogen gas from a solid feedstock, such as sodium borohydride. In the presence of water, sodium borohydride releases hydrogen gas slowly. In order to be used as an efficient source of energy, this reaction needs to be catalyzed so the reaction happens at a sufficient rate. One area of catalysis is the noble metals such as gold at the nanoscale. Using metal nanoparticles is a cost-effective way to use these metals as a catalyst, because much less of the bulk precursor is needed. Without a support, the nanoparticles will not be as effective, so aerogels of gold nanoparticles were synthesized and tested to determine its effectiveness as a catalyst [1]. The evolution of hydrogen was measured using a previously described water displacement system [2,3]. The data show an increase in the efficiency of the generation of hydrogen gas with the addition of gold aerogels when compared to the un-catalyzed reaction. The gold aerogel catalyzed reaction has a rate constant of 15.8 L mol^-1 hr^-1, compared to the un-catalyzed reaction which produced hydrogen at rate of 6.42 L mol^-1 hr^-1, and was determined to be a second order reaction. This catalyzed process produced 92% more moles of hydrogen gas than the un-catalyzed reaction in the same time period.

References

1. D. Wen, W. Liu, D. Haubold, C. Zhu, M. Oschatz, M. Holzschuh, A. Wolf, F. Simon, S. Kaskel, and A. Eychmüller, ACS Nano, 2559–2567, Feb. 2016.
2. T. Dushatinski, C. Huff, and T. Abdel-Fattah, Applied Surface Science, 385, 282 (2016).
3. C. Huff, T. Dushatinski, A. Barzanji, N. Abdel-Fattah, K. Barzanji, and T. Abdel-Fattah, ECS J Solid State, 6, M69-M71 (2017).