P-N and P-i-N junction silicon microwire arrays for solar energy conversion

从现在到2040年，全球年度能源需求预计将增长约四分之一(《国际能源展望》，2017年9月，9月，9月)。美国能源部)。可再生能源和可靠的能源储存对于满足加拿大北部偏远地区和世界各地的这些能源需求至关重要。更新或建设昂贵的基础设施，特别是核设施，是可取的替代方案。阳光是主要的可再生能源--在短短几个小时内，全球发生的太阳能事故总数就超过了我们每年的能源需求。尽管光伏和电池技术取得了长足的进步，但提高储能密度和降低成本仍然是挑战。此外，这些技术的原材料严重依赖于高度受限的供应链。以化学键的形式利用和存储太阳能是解决能量存储密度问题的一项引人注目的探索。使用地球上丰富的材料来捕捉太阳能，制定了最基本的资源管理原则，同时造福于偏远(北部)和发展中的社区。这项提案中的研究将开发基于太阳能的燃料发电的关键技术：以最简单的化学键(氢)存储能量，或将二氧化碳转化为可用燃料。利用化学气相沉积的一种变种，富土硅将被用来以低成本制造具有优良性能特性的高保真单晶微线。我的团队将制造多组分硅微线，包括从掺硼区域到掺磷区域的过渡。这一过渡区的电气特性将为原型太阳能燃料发电组件开辟新的设计路径。当集成到太阳能收集器中时，这些新的硅微线将从阳光中吸收能量，并驱动化学反应，如将水分解为氢和氧气气体，或将二氧化碳还原为碳燃料。最终，这些新的太阳能燃料发电设备将满足关键的能源需求，特别是在发展中和偏远社区。

Annual global energy demands are projected to rise by roughly a quarter between now and 2040 (International Energy Outlook, Sept 2017, Dept. of Energy, USA). Renewable energy sources and reliable energy storage are critical to meeting these energy needs in northern, remote areas of Canada and worldwide. Alternatives to renewing or building costly infrastructure, especially nuclear installations, are desirable. Sunlight is the principal renewable energy resource - in a handful of hours the total solar energy incident on the globe exceeds our annual energy demands. Despite great strides in photovoltaic and battery technology, increasing energy storage density and reducing cost remain challenges. In addition, the raw materials for these technologies rely heavily on highly-restricted supply chains. Harnessing and storing solar energy in chemical bonds represents a compelling quest that resolves the issue of energy storage density. Using earth-abundant materials to capture solar energy enacts the most basic tenets of resource stewardship while benefitting remote (northern) and developing communities.The research in this proposal will develop key technologies for solar-based fuel generation: storing energy in the simplest chemical bond (hydrogen) or converting carbon dioxide into a useable fuel. Using a variant of chemical vapor deposition, earth-abundant silicon will be used to fabricate high-fidelity single-crystal microwires with excellent performance characteristics at low cost. My team will fabricate multicomponent silicon microwires that incorporate a transition from a boron-doped region to a phosphorus-doped region. The electrical characteristics of this transition region will open up new design pathways for prototype solar fuel generation components. When integrated into a solar collector, these new silicon microwires will absorb energy from sunlight and drive a chemical reaction, such as splitting water into hydrogen and oxygen gas or reducing carbon dioxide into a carbon fuel. Ultimately, these new solar-powered fuel generating devices will address critical energy needs, particularly in developing and remote communities.