Asymmetric Synthesis and Study of Platinum Metallahelicenes in Circularly Polarised Phosphorescent Organic Light Emitting Diodes (CP-PHOLEDs)

有机发光二极管(OLED)需要位于两个电极之间的有机半导体材料的发光层，其中至少一个电极是透明的。由于薄尺寸、更快的切换速度和更高的对比度，这些设备正在给显示技术带来革命性的变化。事实上，目前这类设备的市场价值为25亿美元。发射圆偏振电致发光(CPEL)的器件在改进的LCD背光、彩色图像检测和立体显示、光通信和量子计算等光子技术方面应该具有巨大的平移潜力，但直接产生CPEL的问题迄今尚未解决。这项技术的成功开发有赖于圆偏振可控、发射波长可调、颜色纯度高的发光器件的生产。虽然宽带反射偏振器可以作为OLED器件中的无源元件来实现CPEL，但直接产生CPEL将更加优雅，而且在能源效率和生产成本方面都是有利的。这项研究将开发有效的方法来合成本征手性磷光分子，并将其用于制备CP电致发光器件，试图展示高效的CPEL。圆偏振电致发光(CPEL)的成功直接产生将对包括物理和材料科学在内的一系列学科产生革命性的影响。这类工作将对现有知识产生重大影响，这些知识可在若干翻译领域加以利用。英国是OLED技术的先驱，需要新的创新来保持这一地位。事实上，前首席科学顾问大卫·金爵士已经认识到了这一潜在的突出之处：“在英国，我们在一项可以消除硅芯片的技术方面处于世界领先地位”，“我说的是塑料电子产品”。以替代LCD背光为例，当前的技术依赖于偏振滤光片，这种滤光片有效地切断了这些显示器中使用的75%的光。再加上滤色器和设备接口处的吸收，只有4%的所用光被透过。偏振光源的使用，加上可调的颜色成分，将消除这种需要，从而导致显著更节能的显示器。这种碳足迹较低的显示器将对环境产生明显的影响。

Organic light emitting diodes (OLEDs) require an emissive electroluminescent layer of an organic semiconductor material located between two electrodes, where at least one of the electrodes is transparent. Such devices are revolutionising display technologies due to thin dimensions, faster switching and higher contrast ratios. Indeed, currently the market for such devices is valued at >$2.5B. Devices that emit circularly polarised electroluminescence (CPEL) should have vast translational potential in photonic technology, such as improved LCD backlighting, colour-image detection and stereoscopic displays, optical communication, and quantum computing, however to date the problem of directly generating CPEL has not been solved. Successful development of this technology is reliant on the production of light-emitting devices of controllable circular polarisation, tuneable emission wavelength, and high colour purity. While wide-band reflective polarisers may be used as passive components in OLED devices to achieve CPEL, the direct generation of CPEL would be far more elegant, and favourable in terms of energy efficiency and production cost. This research will develop efficient methods to synthesise intrinsically chiral phosphorescent molecules and use these to fabricate CP electroluminescent devices, in an attempt to demonstrate highly efficient CPEL. The successful direct generation of circularly polarised electroluminescence (CPEL) would have a transformative effect on a range of disciplines including physics and materials science. Such work would have significant impact on current knowledge, which could be exploited in a number of translational areas. The UK is a pioneer of OLED technology and needs new innovation to maintain this position. Indeed, former chief scientific advisor Sir David King has recognised this potential highlighting "in Britain we have a world-leading position in a technology that could wipe out the silicon chip" "I am talking about plastic electronics". Taking alternative LCD backlighting as one example of the exploitation of this work, current technologies rely on polarising filters that effectively cut out 75% of the light used in these displays. Combined with absorption by the colour filters and at device interfaces, only 4% of the light used is transmitted. The use of a polarised light source, coupled with tuneable colour components would remove this need, thus leading to significantly more energy efficient displays. Such displays with a lowered carbon footprint would be of clear environmental impact.