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.
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机译：多孔碳已经被广泛地研究用于氢存储，但是迄今为止，似乎对其存储容量具有上限。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 m 2 g -1 ）和孔体积（1.8 cm 3 g < sup> -1 ）几乎全部（> 90％）来自微孔，具有富氧特性。碳在-196CC和20 bar下的重量氢吸收量增加（总计8.1 wt％，过量7.0 wt％），在30 bar下的总吸收量增加到8.9 wt％，并且体积吸收量达到44 g l -1 在20 bar，48 g l -1 在30 bar。在室温下，它们仅在30bar的压力下最多可存储0.8 wt％（过量）和1.2 wt％（总）的氢，氢的等规吸附热量高于10 kJ mol -1 。
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