Porous carbon fibers for effective hydrogen evolution

Abstract

Carbon fibers (CFs) with unique physicochemical properties have been considered as a sustainable material for use as a catalytic support for hydrogen evolution reaction (HER). Porous carbon microfibers (PCFs) were generated by utilizing the needle less electrospinning technology (NLE). The first approach involved the formation of porosity in precursor polyacrylonitrile/polyvinylpirolidone (PAN/PVP) fibers by washing out PVP and carbonization of remaining PAN. Although the sufficient porosity was achieved with increasing PVP content, the total bulk porosity was lost. The second approach was simple removal of PVP, based on different polymer degradation process at high temperatures. The most efficient way was utilization of sodium dodecyl sulphate (SDS) as an anionic surfactant. Binding SDS on PVP polymer chain caused the formation of micelles, which formed regular porous structures in the fibrous carbon matrix after carbonization. The formation of porosity and electrocatalytic activity of CFs after carbonization in Ar and H2 reduction atmosphere were studied. The electrocatalytic results have pointed out that the composition of precursor fibers PAN/PVP/SDS heat treated without previous preoxidation process, carbonized in Ar atmosphere and followed in H2 atmosphere can be efficiently used as a porous material platform for different modification and further application as a potential electrocatalysts for HER.