Instilling Defect-Tolerance in ABZ2 Photovoltaic Materials

向 ABZ2 光伏材料灌输缺陷容限

• 批准号: EP/V014498/2
• 负责人: Robert L. Z. Hoye
• 金额: $ 38.78万
• 依托单位: University of Oxford
• 依托单位国家: 英国
• 项目类别: Research Grant
• 财政年份: 2023
• 资助国家: 英国
• 起止时间: 2023 至 无数据
• 项目状态: 未结题
• 来源: https://gtr.ukri.org/projects?ref=EP%2FV014498%2F2
• 关键词: Instilling; Defect; Tolerance; ABZ2; Photovoltaic

This project aims to develop a new class of semiconductors for photovoltaics (PVs) that can tolerate defects to achieve high efficiencies when manufactured by low capital-intensity and scalable methods. PVs produce clean electricity from sunlight, and their deployment in the UK needs to accelerated by over an order of magnitude so that we can meet our legislated net-zero CO2 emissions target by 2050. New thin film PV materials are urgently needed. Thin film PVs can be used in tandem device structures, in which they are deposited on top of silicon PVs (which dominate the market) or smaller-bandgap thin film PVs. These tandem devices convert a larger fraction of the solar spectrum into electrical energy and can achieve efficiencies surpassing the best single-junction devices, which will be vital for accelerating utility-scale PV deployment. Thin film PVs can also be used as energy-harvesting roof-tiles, windows or cladding to enable sustainable carbon-neutral buildings. But across all applications, it is essential that the materials are efficient when made with by low cost manufacturing methods. The limiting factor is the deleterious role of point defects, such as vacancies. In traditional semiconductors, these point defects introduce energy levels deep within the bandgap and cause irreversible losses in energy. Minimising the density of these defects often requires expensive manufacturing routes. Defect-tolerant semiconductors circumvent these limitations by forming defect levels close to the band-edges (i.e., shallow), where they are less harmful. Such materials were rare until the recent serendipitous discovery of the lead-halide perovskites. Grown cheaply by solution-processing, these polycrystalline materials have over a million times more defects than silicon but are already more efficient in PVs than multi-crystalline silicon. A critical question is whether defect-tolerance can be found in other classes of materials that are free from the toxicity burden of the halide perovskites. This work aims to develop a set of design rules to pinpoint lead-free defect-tolerant semiconductors, and systematically develop these materials into efficient, stable PVs that can be deployed on the terawatt scale. The materials focussed on are ABZ2 compounds, where A is a monovalent cation, B a divalent cation and Z a divalent anion. These materials already show promising signs hinting at defect-tolerance. My approach draws off my experimental strengths in the control of complex thin films. I hypothesise that materials forming shallow traps can be identified through their crystal structure, band-edge orbital composition and degree of cation-anion orbital overlap. I will experimentally elucidate the role of each property by tuning the composition of a small set of ABZ2 materials to vary one property at a time. Defect tolerance will be measured by intentionally inducing vacancies and measuring their effect on charge-carrier lifetime and electronic structure. These design rules will be applied to identify the most promising ABZ2 materials, which will be grown by scalable solution- and vapour-based methods. I will optimise their growth using a fast experimental feedback loop to achieve materials with promising bulk properties for solar absorbers. Such materials will be developed into PVs, drawing off my skills and experience in device engineering. This work is extremely timely and will lead the emerging area of defect-tolerant semiconductors away from toxic perovskites. The new materials can ultimately become commercial contenders for tandem or building-integrated PVs, and therefore impact on the £120B PV industry. These new materials can also have much broader impact and be used, for example, as cheap but efficient materials for clean solar fuel production or biosensors. This project sets the key foundations for achieving these exciting possibilities and will enable me to set-up my group with a cutting-edge programme.

该项目旨在开发一种新型光伏半导体（PV），当通过低资本密集度和可扩展的方法制造光伏发电时，可以容忍缺陷以实现高效率，并且它们在英国的部署需要加速。一个数量级以上，以便我们能够在 2050 年实现法定的二氧化碳净零排放目标。迫切需要新的薄膜光伏材料可以同时使用。器件结构，其中它们沉积在硅光伏器件（主导市场）或较小带隙薄膜光伏器件的顶部，这些串联器件将大部分太阳光谱转化为电能，并且可以实现超越最佳单器件的效率。结装置，这对于加速公用事业规模的光伏部署至关重要。薄膜光伏还可以用作能量收集屋顶瓦、窗户或覆层，以实现可持续的碳中和建筑。但在所有应用中，通过低成本制造方法制造的材料必须高效，限制因素是点缺陷的有害作用，例如在传统半导体中，这些点缺陷会在半导体深处引入能级。最小化这些缺陷的密度通常需要昂贵的制造路线，通过在靠近带边缘（即浅）的地方形成缺陷能级来规避这些限制，这样它们的危害较小。材料直到最近偶然发现通过溶液加工廉价生长的卤化铅钙钛矿，这些多晶材料的缺陷比硅多一百万倍，但在光伏发电中的效率已经比多晶硅更高。是否可以在其他类别的材料中找到不受卤化物钙钛矿毒性负担的缺陷容忍性。这项工作旨在开发一套设计规则来精确定位无铅。缺陷容错半导体，并将这些材料系统地开发成可在太瓦级上部署的高效、稳定的光伏器件。重点研究的材料是 ABZ2 化合物，其中 A 是一价阳离子，B 是二价阳离子，Z 是二价阴离子。我的方法利用了我在控制复杂薄膜方面的实验优势，我假设形成浅陷阱的材料可以通过其晶体结构、带边轨道组成来识别。我将通过调整一小组 ABZ2 材料的成分以一次改变一个属性，通过有意诱导空位并测量其效果来测量缺陷容限，从而通过实验阐明每种属性的作用。这些设计规则将用于确定最有前途的 ABZ2 材料，这些材料将通过可扩展的基于溶液和蒸汽的方法来生长，我将使用快速实验来优化它们的生长。反馈回路，以获得具有前景的太阳能吸收体性能的材料，这些材料将被开发成光伏器件，利用我在器件工程方面的技能和经验，这项工作非常及时，并将引领缺陷容错半导体的新兴领域。这些新材料最终可以成为串联或建筑一体化光伏发电的商业竞争者，因此对价值 120B 英镑的光伏行业产生影响。材料清洁太阳能燃料生产或生物传感器为实现这些令人兴奋的可能性奠定了关键基础，并使我能够通过尖端计划建立我的团队。

项目成果

Grain Engineering of Sb 2 S 3 Thin Films to Enable Efficient Planar Solar Cells with High Open-Circuit Voltage

Sb 2 S 3 薄膜的晶粒工程可实现具有高开路电压的高效平面太阳能电池

• DOI: http://dx.10.1002/adma.202305841
• 发表时间: 2023
• 期刊: Advanced Materials
• 影响因子: 29.4
• 作者: Liu X

Air-stable bismuth sulfobromide (BiSBr) visible-light absorbers: optoelectronic properties and potential for energy harvesting

空气稳定的磺溴化铋 (BiSBr) 可见光吸收剂：光电特性和能量收集潜力

• DOI: http://dx.10.1039/d3ta04491b
• 发表时间: 2023
• 期刊: Journal of Materials Chemistry A
• 影响因子: 11.9
• 作者: Guo X

Fast Near-Infrared Photodetectors Based on Nontoxic and Solution-Processable AgBiS 2

基于无毒且可溶液处理的 AgBiS 2 的快速近红外光电探测器

• DOI: http://dx.10.1002/smll.202310199
• 发表时间: 2023
• 期刊: Small
• 影响因子: 13.3
• 作者: Huang Y

Layered BiOI single crystals capable of detecting low dose rates of X-rays

能够检测低剂量率X射线的层状BiOI单晶

• DOI: http://dx.10.1038/s41467-023-38008-4
• 发表时间: 2023
• 期刊: Nature Communications
• 影响因子: 16.6
• 作者: Jagt R

Bandlike Transport and Charge-Carrier Dynamics in BiOI Films.

BiOI 薄膜中的带状传输和载流子动力学。

• DOI: http://dx.10.1021/acs.jpclett.3c01520
• 发表时间: 2023
• 期刊: The journal of physical chemistry letters
• 作者: Lal S