Ward Matthew D, Docherty Ronan, Minion Louis, Shi Xingyuan, Anson Kai, Siligardi Giuliano, Nelson Jenny, Wade Jessica, Fuchter Matthew J
Department of Physics, Imperial College London, South Kensington Campus, Prince Consort Road, London SW7 2AZ, UK.
Centre for Processable Electronics, Imperial College London, South Kensington Campus, London SW7 2AZ, UK.
Nanoscale. 2024 Jun 20;16(24):11623-11632. doi: 10.1039/d4nr01651c.
Circular dichroism spectroscopy is a key probe of the structural and optical properties of chiral materials, however, commercial circular dichroism spectrometers are large, prohibitively expensive and rarely offer environmental control of the sample under test. Using Fresnel rhombs as inexpensive broadband quarter-wave plates, we demonstrate two novel, low-cost (<£2000) and portable imaging systems controlled by our own bespoke open-source control software which are capable of spatially mapping the circular dichroism of chiral solid state films. By coupling these imaging systems with a temperature controlled stage, we show that we can rapidly identify the thermal processing conditions required to maximise circular dichroism in chiral solid state films by measuring circular dichroism during thermal annealing of a sample under test. The accuracy and spatial resolution of these circular dichroism imagers are cross-compared against our previous studies using an existing circular dichroism imaging system at the Diamond Light Source and are shown to be in good agreement, with a sensitivity down to 250 mdeg and a spatial resolution of 100 μm.
圆二色光谱是研究手性材料结构和光学性质的关键手段，然而，商用圆二色光谱仪体积庞大、价格昂贵，而且很少能对被测样品进行环境控制。我们使用菲涅耳菱体作为廉价的宽带四分之一波片，展示了两种新颖、低成本（<2000英镑）且便携的成像系统，它们由我们自己定制的开源控制软件控制，能够对手性固态薄膜的圆二色性进行空间映射。通过将这些成像系统与温度控制平台相结合，我们表明，通过在被测样品的热退火过程中测量圆二色性，我们可以快速确定使手性固态薄膜的圆二色性最大化所需的热处理条件。将这些圆二色性成像仪的精度和空间分辨率与我们之前在钻石光源使用现有圆二色性成像系统进行的研究进行交叉比较，结果显示两者吻合良好，灵敏度低至250 mdeg，空间分辨率为100μm。
