声热极端条件下光电化学水分解材料的结构调控与性能研究

Acoustic cavitation has intrinsically to-be-developed acoustic-thermal extreme conditions of instantaneous heating and rapid quenching, which could be potentially a unique and effective way of modulating the structures and performance of solar energy conversion materials, while the related research has remained so far in its infant stage. This project will thus carry out in-depth studies on how to efficiently exploit and how to uniquely apply the acoustic-thermal conditions, aiming to the structural engineering and performance optimization of the photoelectrochemical water splitting materials. The scenario of placing nanoparticles at the surface of acoustic cavitation bubbles is expected to achieve based on the adsorption/collapse behaviors study of nanoparticles at the liquid/cavitation-bubble interface. We will mainly develop interfacial sonochemical strategies and optimize the operation parameters, to rationally design the native defects and doping states of single component nanoparticles and fusion of different component materials at the air/liquid interface, and will construct photoelectrochemical devices based on the interfacial sonochemical engineered nanoparticles, characterize and optimize the water splitting performance, and finally reveal the relationship between the structural evolution of nanoparticles under the extreme acoustic-thermal condition and their photo energy 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 to set a feasible example of low-cost extreme conditions based exploitation of advanced materials.

声空化效应蕴含待开发瞬间高温/快速冷凝声热极端条件，有望实现独特、有效的太阳能转换材料结构及性能调控，但目前国际上相关研究还处于起步摸索阶段。本项目拟以光电化学水分解材料的结构调控及性能优化为目标牵引，紧紧围绕声热极端条件的有效开发与独特应用展开深入研究。将基于纳米颗粒在液体媒质-空化气泡界面处的吸附、塌缩行为研究，有效实现其在空化气泡表面预置的物理图景，重点发展界面超声策略，优化界面超声工艺参数，研究界面超声对单组分光解水纳米颗粒的本征缺陷和掺杂态调控以及双组分纳米颗粒于气液界面处的熔融复合。以界面超声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，揭示声热极端条件下纳米颗粒结构演化对其光氢转换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结构调控方法及性能优化途径，并为低成本极端条件在新材料学科中的探索提供可行范例。

本项目重点研究了声热极端非平衡条件下，氧化物纳米颗粒的可控制备、电子结构调控及其光解水性能。针对多元金属氧化物纳米化的制备难题，发展了新型、独特且具有普适性的液相脉冲激光辐照方法，获得了常规条件不易获得的系列亚稳超纳材料，并开发了亚稳超纳的激光植入技术，成功将多元金属氧化物超纳颗粒引入钒酸铋母体，创制了异于原子掺杂的、母体材料电子结构及载流子动力学调控的独特有效途径，最终获得光电流密度达到理论极限82%的光电化学水分解材料。此外，将瞬态极端条件拓展至光热极端条件并发展了多元金属氧化物亚稳超纳材料的可控制备及其在太阳能电池等光电转换领域中的应用，为光解水及其他光电转化材料提供了独特结构调控思路及性能优化途径。受本项目资助的工作，已经发表 SCI 收录论文17篇，包括Nature communications、Angewandte Chemie International Edition、Advanced Materials等国际高水平期刊，申请专利4项。代表性研究成果总结如下：.（1）制备：基于光热瞬态极端条件的液相脉冲激光辐照技术可控制备了粒径可控的钒酸铋胶体颗粒，利用同样的技术还制备了BaSnO3纳米晶、制备了尺寸分布均匀、具有较高荧光量子产率的CsPbBr3无机纳米晶。.（2）光电化学水分解研究：构筑了包埋La:BaSnO3 纳米晶的高性能BiVO4 光阳极，制备了高性能的多孔铋酸铜光电极薄膜。利用TiO2晶界修饰，梯度Ti掺杂等策略制备了高性能的氧化铁光电极薄膜。.（3）拓展研究：探索了极端条件下制备的碳点、液态金属、金纳米簇在钙钛矿电池领域的应用。