多元金属氧化物/贵金属纳米复合材料的激光焊接合成及其光电化学性能研究

As a novel photoelectrochemical catalysis material, the controllable preparation of multinary metal oxides is one of the hottest research topics at present. However, it is difficult to obtain highly crystalline, surface clean and size controllable multinary metal oxides nanoparticles via conventional methods. Non-focused laser irradiation in liquid phase has unique effects of selective heating and rapid cooling, which have been successfully applied to the structural control and performance optimization of a variety of materials such as metals and oxides, while the there are few related researches on the multinary metal oxides. This project will thus carry out in-depth studies on how to efficiently exploit and how to uniquely apply the selective heating characteristics of unfocused laser in liquid medium, aiming to the controllable preparation and performance optimization of the multinary metal oxides. And then, based on selective laser welding technology, noble metal nanoparticles will be welded on the surface of multinary metal oxides to further improve the photoelectrochemical catalytic properties. Finally we will construct photoelectrochemical devices based on materials treated by laser, characterize and optimize the water splitting performance, and reveal the relationship between the structural evolution of nanoparticles under the selective laser heating/welding and their photoenergy conversion performance. The successful implementation of this project is highly expected to provide an avenue of unique structural engineering and performance optimization for solar energy water splitting materials, and opens up new application ways for the laser micro-nano fabrication technology.

作为新兴的光电化学催化材料，多元金属氧化物的可控制备是现阶段的热点研究方向之一，然而传统方法很难获得高结晶度、表面干净且尺寸可控的多元金属氧化物纳米颗粒。液相脉冲激光辐照技术蕴含独特的选择性加热以及快速冷却等效应，目前已经实现了金属、氧化物等多种材料的结构调控及性能优化，然而关于多元金属氧化物的研究却鲜见报道。本项目拟以多元金属氧化物的可控制备及性能优化为目标牵引，紧紧围绕加热模式的开发与应用展开深入研究。并通过激光焊接技术在多元金属氧化物表面复合贵金属纳米颗粒，以进一步提高材料的光电催化性能。以选择性激光处理后的材料为构筑单元组装光电化学器件，表征并优化器件的光解水性能，揭示选择性激光辐照处理对材料光电化学性能的内在影响规律。本项目的成功实施，有望为光解水材料提供独特的结构调控方法及性能优化途径，并为选择性激光辐照技术的应用开辟新的途径。

液相脉冲激光辐照技术蕴含独特的选择性加热以及快速冷却等效应，且反应过程温和可控，目前已经实现了金属、氧化物等多种材料的结构调控及性能优化。多元合金、多元金属氧化物等多组分材料在光电领域具有巨大的潜在应用价值，然而传统方法很难制备出尺寸可控、高结晶度且表面干净的产物；另外，液相脉冲激光辐照技术主要集中于固/液体系的研究，即激光与固相靶材在液相媒介中的相互作用，而激光与液/液体系相互作用的研究较少。液态金属在光电等许多领域具有重要的应用价值，然而纳米级液态金属的可控制备仍是现阶段的技术难点。本项目以多元金属氧化物的可控制备及性能优化为目标牵引，紧紧围绕加热模式的开发与应用展开深入研究，实现了微纳米级多元金属氧化物材料的可控制备。产物分析表明此技术所制备的材料具有表面干净、产物纯度高等独特优势，另外研究小组将液相脉冲辐照技术拓展至液/液体系，首次实现了小于10 nm的液态金属胶体的制备，光热蒸发机制研究表明此方法可以推广于多组元金属纳米颗粒可控制备。此外研究小组对所制备材料的在光电器件的构筑及修饰等应用领域进行了系统的探索。最后我们分别基于热压转移技术及纳米晶包埋技术，以脉冲激光处理后的材料为构筑单元组装光电化学器件，并将激光处理后的材料修饰在钙钛矿太阳能电池以及光电化学水分解器件的光活性层中，实现了光伏及光电化学水分解器件性能的优化。本研究系统探索了选脉冲激光辐照处理对材料光电性能的内在影响规律，拓展了液相脉冲激光辐照技术的应用领域。