Gupta Ritu, Rao K D M, Srivastava Kartikeya, Kumar Ankush, Kiruthika S, Kulkarni Giridhar U
Chemistry & Physics of Materials Unit and Thematic Unit of Excellence in Nanochemistry, Jawaharlal Nehru Centre for Advanced Scientific Research , Jakkur P.O., Bangalore 560 064, India.
ACS Appl Mater Interfaces. 2014 Aug 27;6(16):13688-96. doi: 10.1021/am503154z. Epub 2014 Jul 8.
Transparent conducting electrodes (TCEs) have been made on flat, flexible, and curved surfaces, following a crack template method in which a desired surface was uniformly spray-coated with a crackle precursor (CP) and metal (Ag) was deposited by vacuum evaporation. An acrylic resin (CP1) and a SiO2 nanoparticle-based dispersion (CP2) derived from commercial products served as CPs to produce U-shaped cracks in highly interconnected networks. The crack width and the density could be controlled by varying the spray conditions, resulting in varying template thicknesses. By depositing Ag in the crack regions of the templates, we have successfully produced Ag wire network TCEs on flat-flexible PET sheets, cylindrical glass tube, flask and lens surface with transmittance up to 86%, sheet resistance below 11 Ω/□ for electrothermal application. When used as a transparent heater by joule heating of the Ag network, AgCP1 and AgCP2 on PET showed high thermal resistance values of 515 and 409 °C cm(2)/W, respectively, with fast response (<20 s), requiring only low voltages (<5 V) to achieve uniform temperatures of ∼100 °C across large areas. Similar was the performance of the transparent heater on curved glass surfaces. Spray coating in the context of crack template is a powerful method for producing transparent heaters, which is shown for the first time in this work. AgCP1 with an invisible wire network is suited for use in proximity while AgCP2 wire network is ideal for use in large area displays viewed from a distance. Both exhibited excellent defrosting performance, even at cryogenic temperatures.
透明导电电极（TCEs）已被制备在平面、柔性和曲面上，采用裂纹模板法，即先在所需表面均匀喷涂裂纹前驱体（CP），然后通过真空蒸发沉积金属（Ag）。源自商业产品的丙烯酸树脂（CP1）和基于SiO2纳米颗粒的分散体（CP2）用作CP，以在高度互连的网络中产生U形裂纹。裂纹宽度和密度可通过改变喷涂条件来控制，从而导致模板厚度不同。通过在模板的裂纹区域沉积Ag，我们成功地在平面柔性PET片材、圆柱形玻璃管、烧瓶和透镜表面制备了Ag线网络TCEs，用于电热应用时，其透过率高达86%，方阻低于11Ω/□。当通过Ag网络的焦耳热用作透明加热器时，PET上的AgCP1和AgCP2分别显示出515和409℃·cm²/W的高热阻，响应速度快（<20秒），仅需低电压（<5V）即可在大面积上实现约100℃的均匀温度。弯曲玻璃表面上的透明加热器也有类似的性能。在裂纹模板的背景下进行喷涂是一种制备透明加热器的有效方法，这项工作首次展示了这一点。具有不可见线网络的AgCP1适合近距离使用，而AgCP2线网络则非常适合用于从远处观看的大面积显示器。即使在低温下，两者都表现出优异的除霜性能。
