Porous carbons have been extensively investigated for hydrogen storage but, to date, appear to have an upper limit to their storage capacity. Here, in an effort to circumvent this upper limit, we explore the potential of oxygen-rich activated carbons. We describe cellulose acetate-derived carbons that combine high surface area (3800?m2?g?1) and pore volume (1.8?cm3?g?1) that arise almost entirely (90%) from micropores, with an oxygen-rich nature. The carbons exhibit enhanced gravimetric hydrogen uptake (8.1?wt% total and 7.0?wt% excess) at ?196?°C and 20?bar, rising to a total uptake of 8.9?wt% at 30?bar, and exceptional volumetric uptake of 44?g?l?1 at 20?bar, and 48?g?l?1 at 30?bar. At room temperature they store up to 0.8?wt% (excess) and 1.2?wt% (total) hydrogen at only 30?bar, and their isosteric heat of hydrogen adsorption is above 10?kJ?mol?1.
展开▼
机译：多孔碳已经被广泛地研究用于氢存储，但是迄今为止，似乎对它们的存储容量具有上限。在这里，为了避免这个上限，我们探索了富氧活性炭的潜力。我们描述了醋酸纤维素衍生的碳，它们结合了高表面积（3800？m2？g？1）和孔体积（1.8？cm3？g？1），这些孔几乎全部（> 90％）来自微孔，并且富含氧气性质。碳在？196°C和20？bar下的重量氢吸收量增加（总量为8.1？wt％，过量7.0？wt％），在30？bar下的总吸收量增加到8.9？wt％，并且具有异常的体积吸收在20 bar时为44 g g l l 1，在30 bar时为48 g g l l 1。在室温下，它们仅在30巴的压力下最多可存储0.8？wt％（过量）和1.2？wt％（总）氢，并且它们的氢吸附等排热超过10kk？mol？1。
展开▼
