Spectroscopy-led Development of Organic Photocatalysts for Sustainable Energy Production

光谱主导的有机光催化剂开发用于可持续能源生产

• 批准号: RGPIN-2019-05521
• 负责人: Godin, Robert
• 金额: $ 1.75万
• 依托单位: University of British Columbia
• 依托单位国家: 加拿大
• 项目类别: Discovery Grants Program - Individual
• 财政年份: 2021
• 资助国家: 加拿大
• 起止时间: 2021-01-01 至 2022-12-31
• 项目状态: 已结题
• 来源: https://www.nserc-crsng.gc.ca/ase-oro/Details-Detailles_eng.asp?id=738346
• 关键词: Spectroscopy; led; Development; Organic; Photocatalysts

Renewable solar energy needs to be paired with energy storage to overcome the hourly mismatch between solar energy supply and energy demands. Inspired by the natural photosynthesis of plants, solar energy can be stored in high-density chemical bonds. Solar fuels - high energy molecules generated from sunlight - can be produced by photocatalysts that drive water splitting (to make H2) or photoreduction of CO2 (to make liquid fuels). To accelerate the transition to a low-carbon society, cost-effective photocatalysts that produce solar fuels with improved efficiencies must be developed. Carbon nitride (CNx) has emerged as a leading cost-effective photocatalyst. CNx can be synthesized by simple heat treatment of inexpensive molecules and has the requisite (photo)chemical stability. High photocatalytic efficiencies (quantum yields up to 50%) for H2 photogeneration have been demonstrated using sacrificial oxidation substrates. To close the sustainable solar fuel cycle, these substrates must be replaced with H2O, the product generated when energy is released. However, H2O oxidation is more challenging. The resulting solar-to-fuel efficiency < 1% is far from the targeted commercialization barrier of 10%. My research program will develop the structure-activity relationships needed to engineer superior photocatalysts. The advanced spectroscopic technique of transient absorption spectroscopy (TAS) will shed light on the photophysics of CNx and identify the most crippling efficiency bottlenecks. The impact of energetic, structural and spatial heterogeneities on photoefficiency is poorly understood. To gain a holistic view of the key processes that determine photoactivity, my group will investigate the charge carrier dynamics of CNx modified on three different axes: (nano)morphology, chemical nature of terminal groups, and deposited redox cocatalysts. To uncover spatial heterogeneities in CNx, I will develop microsecond - second transient absorption microscopy (TAM) to map out processes such as charge trapping, charge accumulation and interfacial charge transfer. Spectroscopy will yield crucial photophysical and structural insights needed to direct synthetic modifications of photocatalysts. The synergistic spectroscopic and synthetic approach will optimize CNx morphology and internal photophysics, required for both efficient H2 production and CO2 photoreduction. My long-term vision is to take advantage of the optimized CNx photophysics to develop solar-driven carbon capture and utilization, using CNx and light to sequester CO2 within materials with long lifespans. HQP involved in the research program will gain a unique combination of synthetic, spectroscopic, communication, and management skills that make them attractive to the growing clean technology sector. HQP will contribute to the clean energy sector and the important H2 industry that will surpass US$200 Bn by the end of 2025, developing Canada's economy and helping reach lower CO2 emissions targets.

可再生太阳能需要与储能相结合，以克服太阳能供应与能源需求之间每小时的不匹配。受植物自然光合作用的启发，太阳能可以储存在高密度的化学键中。太阳能燃料——由阳光产生的高能分子——可以通过光催化剂产生，光催化剂驱动水分解（产生氢气）或光还原二氧化碳（产生液体燃料）。为了加速向低碳社会的转型，必须开发具有成本效益的光催化剂，以提高效率生产太阳能燃料。氮化碳 (CNx) 已成为一种领先的经济高效的光催化剂。 CNx 可以通过廉价分子的简单热处理来合成，并且具有必要的（光）化学稳定性。使用牺牲氧化底物已证明 H2 光生具有高光催化效率（量子产率高达 50%）。为了完成可持续的太阳能燃料循环，必须用水（能量释放时​​产生的产物）代替这些基质。然而，H2O 氧化更具挑战性。由此产生的太阳能燃料效率 < 1% 距离商业化目标 10% 还很远。我的研究计划将开发设计优质光催化剂所需的结构-活性关系。先进的瞬态吸收光谱 (TAS) 光谱技术将揭示 CNx 的光物理学并确定最严重的效率瓶颈。人们对能量、结构和空间异质性对光效率的影响知之甚少。为了全面了解决定光活性的关键过程，我的小组将研究在三个不同轴上修饰的 CNx 的载流子动力学：（纳米）形态、末端基团的化学性质和沉积的氧化还原助催化剂。为了揭示 CNx 中的空间异质性，我将开发微秒-秒瞬态吸收显微镜 (TAM) 来绘制电荷捕获、电荷积累和界面电荷转移等过程。光谱学将产生指导光催化剂合成修饰所需的重要光物理和结构见解。协同光谱和合成方法将优化 CNx 形态和内部光物理，这是高效生产氢气和二氧化碳光还原所需的。我的长期愿景是利用优化的 CNx 光物理学来开发太阳能驱动的碳捕获和利用，利用 CNx 和光将二氧化碳封存在长寿命的材料中。 参与该研究项目的 HQP 将获得合成、光谱、沟通和管理技能的独特组合，这使他们对不断发展的清洁技术领域具有吸引力。 HQP 将为清洁能源行业和重要的氢气行业做出贡献，到 2025 年底，贡献将超过 2000 亿美元，发展加拿大经济并帮助实现较低的二氧化碳排放目标。