McMaster University, School of Biomedical Engineering, Hamilton, L8S 4L7, Canada.
McMaster University, Department of Engineering Physics, Hamilton, L8S 4L7, Canada.
Sci Rep. 2017 Feb 13;7:42543. doi: 10.1038/srep42543.
Three-dimensional electrodes that are controllable over multiple lengthscales are very important for use in bioanalytical systems that integrate solid-phase devices with solution-phase samples. Here we present a fabrication method based on all-solution-processing and thin film wrinkling using smart polymers that is ideal for rapid prototyping of tunable three-dimensional electrodes and is extendable to large volume manufacturing. Although all-solution-processing is an attractive alternative to vapor-based techniques for low-cost manufacturing of electrodes, it often results in films suffering from low conductivity and poor substrate adhesion. These limitations are addressed here by using a smart polymer to create a conformal layer of overlapping wrinkles on the substrate to shorten the current path and embed the conductor onto the polymer layer. The structural evolution of these wrinkled electrodes, deposited by electroless deposition onto a nanoparticle seed layer, is studied at varying deposition times to understand its effects on structural parameters such as porosity, wrinkle wavelength and height. Furthermore, the effect of structural parameters on functional properties such as electro-active surface area and surface-enhanced Raman scattering is investigated. It is found that wrinkling of electroless-deposited thin films can be used to reduce sheet resistance, increase surface area, and enhance the surface-enhanced Raman scattering signal.
对于将固相器件与溶液相样品集成的生物分析系统而言，可在多个长度尺度上进行控制的三维电极非常重要。本文提出了一种基于全溶液处理和智能聚合物薄膜褶皱的制造方法，非常适合可调三维电极的快速原型制作，并且可扩展到大批量制造。尽管全溶液处理是一种有吸引力的低成本制造电极的替代方法，与气相技术相比，但它通常会导致薄膜导电性差和与基底结合力差。通过使用智能聚合物在基底上形成重叠褶皱的保形层，来缩短电流路径并将导体嵌入聚合物层中，从而解决了这些局限性。通过化学镀在纳米颗粒种子层上沉积这些褶皱电极，研究了在不同沉积时间下的结构演变，以了解其对孔隙率、褶皱波长和高度等结构参数的影响。此外，还研究了结构参数对功能特性（如有效表面积和表面增强拉曼散射）的影响。结果表明，化学镀沉积薄膜的褶皱处理可以降低薄膜电阻、增加表面积，并增强表面增强拉曼散射信号。
