Nanostructured Phosphorus Based Compounds and Their Application Towards Electrochemical Hydrogen Generation

Abstract

The development of sustainable, eco- friendly and renewable energy sources is required to newlineaddress the increasing demand for energy and environmental concerns. Hydrogen (H 2 ) is one newlineof the most appealing renewables for future energy applications. At present, steam methane newlinereforming method is used for large scale production of hydrogen which also consumes newlineconventional fossil fuels and releases greenhouse gases such as CO 2 . The generation of newlinehydrogen through water splitting gains much researcher s attention due to no generation of newlinecarbon footprint. Hydrogen production from the electrolysis of water is one of the superior newlinetechniques owing to the production of high purity hydrogen at large scale without emission newlineof greenhouse gases. The electrolysis of water is carried out in two half-reactions, which are newlinehydrogen evolution reaction (HER) and oxygen evolution reaction (OER). The well-known newlineequation for half-cell reaction of HER is 2H + (aq) + 2e - and#8594; H 2 (g). To carry out this half-cell newlinereaction, materials based on platinum are considered as the best electrocatalyst. However, the newlineexpensive nature of platinum and its less abundancy make them obstructed to be used in newlinelarge scale production of H 2 . Therefore developing cost-effective and highly efficient newlineelectrocatalysts for the hydrogen evolution reaction (HER) is critical to promoting hydrogen newlinegeneration from mild techniques. In the present thesis, we have developed a low-temperature newlineprocess to synthesize ultrathin Co 2 P 4 O 12 and Ni 2 P 4 O 12 nanosheets. The Co 2 P 4 O 12 and newlineNi 2 P 4 O 12 nanosheets show an efficient catalytic activity towards HER and high stability due newlineto presence of P 4 O 124- cyclic ring in acidic medium. Further, the catalytic activity of metal newlinecyclotetraphosphate was enhanced by synergistic effect of bimetallic cyclotetraphosphates newline(CoNiP 4 O 12 ). Despite that composite of bimetallic cyclotetraphosphates with reduced newlinegraphene oxide (rGO) has also been explored to increase its surface area and electronic newlineproperties. We have also investigat