Enhanced catalytic dehydrogenation of LiBH4 by carbon-supported Pd nanoparticles

Abstract

The investigation of thermally induced dehydrogenation of LiBH(4) catalyzed by carbon-supported Pd nanoparticles (Pd/C) reveals that LiBH(4) doped with the Pd/C catalysts shows superior dehydrogenation performance, compared to dehydrogenation in the absence of catalyst, even at very low catalyst content. We have found that smaller Pd nanoparticles result in greater enhanced catalytic dehydrogenation of LiBH(4) than do larger Pd nanoparticles. For doping with 10 wt.% catalyst of an average Pd particle diameter of ca. 5.3 nm, thermal dehydrogenation of LiBH(4) is found to start at ca. 280 degrees C with a total weight loss of 15.8 wt.% for the full temperature range. With increased loading of catalyst within a LiBH(4) sample, the onset dehydrogenation temperature and the two main desorption peaks from LiBH(4) are found to decrease while the hydrogen release amount is found to increase. All the hydrogen of ca. 18.5 wt.% can be released from LiBH(4) below 580 degrees C at a catalyst doped level of 50 wt.%. Importantly, we observed a reversible hydrogenation/dehydrogenation with a capacity of approximately 4.3 wt.%. Pd nanoparticles are found to play an important role in the catalyzed dehydrogenation/rehydrogenation of LiBH(4).