Identifier: TDX:2955
Authors: Han, Lijuan
Abstract:
As a form of energy, electricity is one of the main forms for the utilization of renewable energy sources, such as photovoltaics, turbines, hydroelectricity and so on. However, electricity is not the most practical for many applications because it is difficult to store and transport efficiently. Thus, the storage, transport and extraction technologies of electricity in cheap and efficient ways becomes necessary for the widespread use. One plausible approach is to collect and store electricity in chemical bonds as chemical fuels, and then to sustainably extract electricity from chemical fuels in fuel cells on demand.
The technologies for chemical fuels generation strongly relies on the half-cell water oxidation for an abundant supply of protons and electrons. However, the development of upscalable water oxidation electrocatalysts from earth–abundant metals able to operate in neutral or acidic environments and low overpotentials remains a fundamental challenge. In this thesis, we utilized various synthetic routes to prepare PBAs complexes as electrochemical water oxidation catalysts, and then assessed their catalytic activity, stability and corrosion resistance during water oxidation by electrochemical, spectroscopic and structural studies. Furthermore, cobalt hexacyanoferrate (CoFePB) has demonstrated its excellent activity and selectivity towards formic acid/formate oxidation to CO2 with full faradaic efficiency in aqueous media over a large pH range. Taking advantage of its electrocatalytic activity, we have developed an inexpensive cerium/formate liquid flow fuel cell with a carbon felt cathode for the Ce4+ reduction and with CoFePB anode for formate oxidation. This simple and noble-metal-free fuel cell opens promising perspectives for efficient electricity generation in the low-temperature aqueous fuel cell.
Repositori URV