Nanomaterials engineering for hydrogen generation reactions: challenges and prospects

The energy security and supplies of energy are the key components for progressing countries. Renewable energy resources are rapidly being recognized as clean sources of energy to withstand damages to environment and to avoid future crisis. Many materials related challenge exist in electrochemistry covering the entire span of electrode materials as an active component of fuel cells and next generation energy conversion devices. With this motivation, surface engineering at nanoscale plays an important role in energy generation, conversion and utilization applications. Our current research is systematically examining and developing the efficient and cost effective electro-catalysts for hydrogen generation reactions wherein metal nanostructures anchored on carbon based materials (enhancing surface area/activity) and substitutional doping of nonmetal demonstrate extraordinary electro-catalytic performance in water splitting and other hydrogen generation reactions. CZTS nano-electrocatalyst (2.6+0.4 nm) for HER is synthesized by one step sonochemical method with uniform size distribution, which shows promisingly lower onset potential with higher current density and longer stability. We believe that our study will facilitate the development of new and efficient HER catalyst based on transitional metal chalcogenides. In line with this, one of our report represents, a facile, wet chemical synthetic method to metal-free, yet catalytically active, B-substituted graphene (B-SuG) and can serve as an efficient metal-free, electrocatalyst for hydrogen evolution reaction (HER). In addition to this, Fullerene (C60; 15 +2 nm) sensitized with silver nanoparticles (Ag NPs; 10 + 0.5 nm) (Ag@C60) as efficient electrocatalyst is reported for the oxidation of hydrazine, which demonstrates activity close to that of Pt in acidic, neutral and basic media. The observed efficient electrocatalytic activity of the as-synthesized electrode is attributed to the co-operative response and associated structural defects due to their oxidative functionalization along with their cooperative functioning at nanodimensions. We expect that these findings will stimulate future research on synthesis of other innovative and sustainable metal-free nanomaterials and investigation of the fundamental structure-property relationships for renewable energy and other applications. (author)