Nanocrystalline Photodiodes: Novel Devices for Water Splitting

世界上的化石燃料储量正在迅速减少，这也是全球变暖的主要原因。太阳能是一种主要的、尚未开发的能源，可以很容易地满足当前和未来的全球能源需求。任何太阳能转换装置都必须是每平方米便宜、高效和持久的。在这个项目中，新的无机水分解系统，称为宏观光催化二极管电池，mpcd，利用一系列新的和已建立的可见光吸收光催化剂材料，将被开发用于在单独的隔间中利用阳光分解水。后一个特征是重要的，因为它将最小化，如果不能消除，与混合产物生成相关的各种降低效率的重组反应。该工作计划涉及许多新方面，包括：制备新的纳米颗粒，晶体光催化剂材料，将其制造成不同的新型光电二极管格式，以及合成和利用新的氧化还原催化剂。通过连续热液流合成（CHFS）制备纳米半导体光催化剂，并结合凝胶浇铸坚固的多孔支撑，是一项特别重要和新颖的进展，同样重要的还有通过CVD制备光催化剂薄膜的组合方法。该项目将开发大量的基础科学，用于制造最终的、优化的、高效的mpcd，并包括使用时间分辨瞬态吸收光谱对潜在反应机制的研究。该提案为实现太阳能捕获效率的阶段性变化提供了一条途径，旨在提供高效、可扩展的MPCD技术示范，适合在第二阶段的资助中发展到试点工厂系统。

The fossil fuel reserves of the world are rapidly diminishing and are also the prime cause for global warming. Solar energy represents a major, largely untapped energy source which could easily satisfy current and future global energy demands. Any solar energy conversion device must be inexpensive per m2, efficient and long-lasting. In this programme, novel, inorganic water-splitting systems, called macro-photocatalytic diode cells, MPCDs, utilising a range of new and established visible-light absorbing photocatalyst materials, will be developed for splitting water using sunlight in separate compartments. The latter feature is important as it will minimise, if not eliminate, the various efficiency-lowering recombination reactions associated with mixed product generation. The work programme involves a number of novel aspects including: the preparation of new nanoparticulate, crystalline photocatalyst materials, fabricating them into different novel photodiode formats and the synthesis and utilisation of new redox catalysts. The use of nanoparticulate semiconductor photocatalysts, made via continuous hydrothermal flow synthesis, CHFS, in conjunction with gel casting for robust porous supports, is a particularly important and novel advance, as too is the proposed combinatorial approach to the preparation of photocatalyst films by CVD. The project will develop a significant amount of the underpinning science required for the fabrication of the final, optimised, efficient MPCDs and include a study of the underlying reaction mechanisms, using time-resolved transient absorption spectroscopy. The proposal offers a route to achieving a step change in efficiency for energy capture from the sun and aims to deliver efficient, scalable demonstrators of the MPCD technology, suitable for development into pilot plant systems in the second phase of funding.