Lead has long been a ubiquitous material within the energy industry, with use in the classic lead acid batteries (PbO2 and PbSO4), lead telluride thermoelectrics, and the emerging class of lead perovskite photovoltaics. Photoactive films of highly (110) orientated alpha-PbO have been synthesised through the electrochemical oxidation of Pb foil. Using a combination of electrochemical growth and x-ray diffraction the growth of these films has been understood as developing from beta-PbO through to highly (110) orientated alpha-PbO as the growth time progresses. This orientation has further been understood as only developing in an out-of-plane manner, with no preferred in-plane orientation observed. PbO2 films have been electroplated onto transparent conducting oxides. A thermal reduction method has been used to reduce these films to Pb3O4, beta-PbO and alpha-PbO. The thermal reduction of PbO2 has been studied in situ using high pressure photoelectron spectroscopy (HiPPES). HiPPES measurements of PbO2 have also yielded results suggesting oxygen vacancy healing in the material. Deep eutectic solvents (DES) have demonstrated excellent application to the recycling of lead-based energy materials. By dissolving the spent material in a DES, the toxic Pb can be selectively electrodeposited out. The technique shows a means for environmentally friendly recycling of lead acid batteries and for lead perovskite solar cells, overcoming one of the main prohibitive steps preventing their marketplace integration. The electronic structure of PbTe has been studied through a combination of hard x-ray photoelectron spectroscopy (HAXPES), soft x-ray photoelectron spectroscopy (SXPS) and density function theory calculations. The results have yielded a thorough understanding of the electronic structure of the PbTe valence band due to the high resolution of the photoelectron spectra and the calculated partial density of states. Using the varying probing depths of HAXPES and SXPS an upward surface band-bending of 0.26 eV has been observed, closely matching theoretical predictions.
| Identifer | oai:union.ndltd.org:bl.uk/oai:ethos.bl.uk:726884 |
| Date | January 2015 |
| Creators | Poll, Christopher |
| Contributors | Payne, David ; Riley, Jason |
| Publisher | Imperial College London |
| Source Sets | Ethos UK |
| Detected Language | English |
| Type | Electronic Thesis or Dissertation |
| Source | http://hdl.handle.net/10044/1/52639 |
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