Influence of oxygen-functional groups on carbon replicas for hydrogen adsorption

In this work, we prepared the ordered nanoporous carbon replicas (CR) by templating method using organized nanoporous silica SBA-15 as a template. The prepared CR samples were chemically modified with H ₃PO ₄ concentrates in order to investigate the hydrogen storage behaviors. From the results, the H ₃PO ₄ treatments were proven to introduce oxygen-functional groups to carbon surfaces and change the textural properties of the samples. Moreover, the amount of hydrogen adsorption for H ₃PO ₄ treated samples was all enhanced except for the excessively treated sample (above 10 M H ₃PO ₄). Consequently, it could be concluded that hydrogen storage is greatly governed by the acidity of the carbon surfaces, resulting in enhancing electron acceptor-donor interactions at the interfaces (carbon surfaces-hydrogen molecules) due to the H ₃PO ₄ treatments.