| In order to meet the growing energy demand, and deal with the upcoming energy crisis as well as eliminate the existing high pollution and high emission energy structure, many researchers have carried out a lot of researching works to develop a variety of renewable and clean energy, and many research questions rest on the fabrication and modification of functional devices. The purpose of this project is to solve some actual problems in the fabrication of DSC and PEMFC, to improve the performances and reduce the production costs by using a domestically developed laser microprocessing equipment and choosing an appropriate laser. The researches in the thesis were focused on UV laser manufacturing a mesh polyimide (PI) thin film with long-range ordered straight micro holes, UV laser fabricating fluorine-doped tin oxide (FTO) thin film micro structure electrodes on glass substrate and1064nm laser improving the function of flexible DSC light anode. A numerical simulation about the UV laser manufacturing long-range ordered straight micro holes was carried out, meanwhile the effects of UV laser ablation parameters on the experimental results and the interaction of UV laser with FTO films were systematically analyzed, which are benefit for theoretical guidance in industrial production.Firstly, aiming at the poor durability and mechanical property of perfluorosulfonic acid membrane (Nafion, DuPont Co), the composite proton exchange membrane (Nafion/PI composite films) which was fabricated by immersing Nafion resin into a reinforcing mesh PI thin film was first proposed to increase the durability of the PEMFC. According to the requirements of the mesh PI thin film, the effects of the main processing parameters (such as laser fluence, pulse number, overlap rate, and scan times) on the size precision and quality of the straight holes fabricated by laser drilling or laser trepanning were investigated by adoping a355nm Nd:YVO4UV laser so as to obtain a optimal parameter combination to fabricate microporous array PI substrate with differen diameter and hole volume fraction. Nafion resin was impregnated into these micro holes of the porous PI sustrate to synthesize a Nafion/PI composite membrane. Otherwise, the effects of hole diameter and hole volume fraction on the properties of the composite membranes were analyzed to determine the various performance indexes of the PEM, the experimental results indicate that highly stable porous polyimide subatrate can be achieved by controlling the laser processing manner, the technological parameters, and the structure of the microporous arrays, the composite proton exchange membrane can achieve a porton conductivity which is very close to that of pure Nafion211membrane, meanwhile, the thermodynamic mechanical capacities of the composite membranes are much better than that of Nafion211and the yield stresses of the composite membranes are2-3times higher than that of the bulk Nafion211membrane, so this type of composite membrane can imporve the durability of the PEMFC without reducing its electrical properties. The experimental results about UV laser ablation of PI films were analyzed in theory, and a numerical simulation about the technological experiment was developed to achieve an industrialization theory which has guiding significance for UV laser processing of polyimide films.Secondly, according that back-contact dye-sensitized solar cells (BC-DSC) has many advantages such as extending the range of the electrode material, reducing the fabrication costs, preventing optical transmission losses and so on, the UV laser with high speed scanner system was adopted to fabricate the symmetric set of interdigitated FTO finger electrodes of the BC-DSC to overcome the disadvantages in conventional photolithography techniques, such as complex production process, low flexibility, high cost, quality defects and so on Methods of front side ablation and back side laser ablation on the FTO films were studied, and a formula was summarized for calculating the focus offset of back side laser ablation to select a more appropriate approach for the fabrication of the FTO micro structured electrodes. A4×4orthogonal design and an assistant experimental design were used to identify the key laser ablation parameters and optimize the parameters for the laser ablation of the FTO films, meanwhile the damage mechanism of the glass substrate was investigated. In addition, the ablation mechanisms of both front and back side laser ablation were elaborated. The experimental results showed that the micro structured electrodes with high size precision and without microcracks could be achieved by adopting a group of optimal laser ablation parameters. The entire graphic microprocessing only took four seconds which is an efficiency acceptable for industrial applications. Mnally, aiming at low efficiency of flexible DSC which was caused by the executed difficult fabrication of TiO2films and the poor contacts between the TiO2nanoparticles, a novel selective laser sintering of TiO2nanoparticle film on plastic substrate was conducted to improve the connection between the TiO2nanoparticles. Two kinds of lasers with different wavelength of355nm and1064nm were used to sinter the TiO2electrodes, and the effects of the laser wavelength on the laser sintering mechanisms were systematically analyzed via micro morphology, Raman micro-spectroscopy, electrochemical impedance spectroscopy, transient photovoltage/photocurrent decay, and the efficiency of flexible DSC. Using the optimal parameters acquired by summarizing experimental data, the electrical contacts between the TiO2nanoparticles could effectively be promoted without damage to the plastic conductive substrate. The near-infrared laser sintering technology could effectively decrease electron transport resistance and increase recombination resistance of the TiO2nanoparticles film characterized, meanwhile the charge collection efficiency was also improved. Thus, compared to the reference sample, the laser sintered film has achieved an improved short-circuit current density from9.2to10.4mA/cm2, fill factor from0.71to0.77, and solar conversion efficiency from4.5%to5.7%. |
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