Laboratory of semiconducting and photoactive "post-graphene" 2D materials, nanomaterials and nanocomposites

半导体和光活性“后石墨烯”二维材料、纳米材料和纳米复合材料实验室

• 批准号: RGPIN-2020-06669
• 负责人: Fanchini, Giovanni
• 金额: $ 2.99万
• 依托单位: University of Western Ontario
• 依托单位国家: 加拿大
• 项目类别: Discovery Grants Program - Individual
• 财政年份: 2020
• 资助国家: 加拿大
• 起止时间: 2020-01-01 至 2021-12-31
• 项目状态: 已结题
• 来源: https://www.nserc-crsng.gc.ca/ase-oro/Details-Detailles_eng.asp?id=718418
• 关键词: Laboratory; semiconducting; photoactive; post; graphene

Visible light, with wavelength between 400 nm and 700 nm, is at the core of optical sciences because it is simple to generate, reflect, transmit and detect it in so many different ways. Virtually any visible-light optical instrument available in everyday's life utilizes radiation that propagates at large distances over the size of the source that generates it. Unfortunately, this "far-field" optics is inherently limited by diffraction in the ability to resolve very small objects, with a resolving power no much less than a wavelength. This indicates that visible light in the far-field is unsuitable for the precise analysis of nanomaterials, quantum dots, and two-dimensional (2D) materials, in which spatial confinement below 1-100 nm is critical and has the potential of unique breakthroughs in terms of new physics and devices. Examples of new devices in which confinement effects are vital include: advanced solar cells that will make energy conversion cleaner, digital memory devices to make our big-data society simpler, nanoporous water filters to clean our environment, and heat spreaders to improve the lifetime of our portable electronics. We have acquired the skills to fabricate many of these devices in-house and, as a team of physicists, we are using proof-of-concept device prototypes to better understand the performance of specific materials incorporated into them. The most fundamental aspects of our research focus on the use of "near-field" visible radiation generated in the proximity of a nano-optical source to overcome diffraction, probe light-matter interaction at the nanoscale, and precisely infer the properties of specific 2D materials, nanomaterials and nanocomposites. We have unique expertise in aperture-type scanning near-field optical microscopy (SNOM) a near-field technique in which atomic force microscopy (AFM) cantilevers with sub-wavelength apertures drilled into them are used to generate localized near-field radiation and scan a sample in the close proximity of this source. Many optical techniques so far implemented only in the far-field will thus be extended to the near-field. The discovery of graphene, a 2D material entirely formed by carbon atoms, has spurred tremendous interest towards the potential of flat materials with confinement along the z-axis, but the next-generation of "post-graphene" 2D materials is still awaiting the most appropriate tools to be analyzed, manipulated and incorporated into proof-of-concept devices to understand their optical properties with high precision. Here, special emphasis will be placed on those 2D materials, nanomaterials and nanocomposites that, differently from graphene, exhibit semiconducting and photoactive properties, such as carbon quantum dots, aerogels, and 2D transition metal oxides and chalcogenides. SNOM tools capable of analyzing these systems are exciting and ideal to train the next-generation of diverse, inclusive and highly-qualified personnel in nano-optics and nano-physics.

可见光在400 nm至700 nm之间的可见光是光学科学的核心，因为它易于以许多不同的方式生成，反射，传输和检测到它。实际上，日常生活中可用的任何可见光仪器都利用辐射在产生它的源源的大小上大大传播。不幸的是，这种“远场”光学固有地受到解决非常小的对象的衍射的限制，而解决的能力也不少于波长。这表明远场中的可见光不适合对纳米材料，量子点和二维（2D）材料进行精确分析，在该材料中，在1-100 nm以下的空间限制至关重要，并且在新物理学和设备方面具有独特的突破。限制效果至关重要的新设备的示例包括：先进的太阳能电池，这些太阳能电池将使能量转换更清洁，数字记忆设备使我们的大数据社会更简单，纳米孔滤水器来清洁我们的环境，并提高散布我们的可移植电子的寿命。我们已经获得了在内部制造许多此类设备的技能，作为一组物理学家，我们使用概念验证设备原型来更好地了解其中包含的特定材料的性能。我们研究的最根本方面集中在使用纳米光源源以克服衍射，纳米级的探测光互动的近端产生的“近场”可见辐射，并精确地推断出特定2D材料，纳米材料，纳米材料和纳米复合材料的性质。我们在光圈型扫描近场光学显微镜（SNOM）方面具有独特的专业知识，其中一种近场技术，其中原子力显微镜（AFM）悬臂具有钻入其中的亚波长孔，用于生成局部化的近场辐射，并扫描了此源的近距离范围。因此，迄今仅在远场实施的许多光学技术将扩展到近场。发现石墨烯是一种完全由碳原子形成的2D材料，激发了人们对沿Z轴限制的平坦材料潜力的巨大兴趣，但是“涂印后” 2D材料的下一代仍在等待最合适的工具，以分析，操纵和融合到卓越的设备中，以了解其优先级的设备，以使其具有高度的精确性。在这里，将特别重点放在那些2D材料，纳米材料和纳米复合材料上，这些材料与石墨烯的不同，具有半导体和光活性特性，例如碳量子点，气凝胶和2D过渡金属氧化物和2D过渡金属氧化物和chalcogenides。能够分析这些系统的SNOM工具令人兴奋，非常理想，可以在纳米式和纳米物理学中培训各种，包容和高度合格的人员的下一代。