In situ fabrication of organic electrochemical transistors on a microfluidic chip
electrodeposition, in situ, microfluidic chip, PEDOT:PSS/GQDs composite, transistor
Microfluid chips integrating with organic electrochemical transistors (OECTs) are useful for manufacturing biosensors with high throughput and large-scale analyses. We report here the utilization of alternating current (AC) electrodeposition to fabricate OECTs in situ on a microfluid chip. With this method, the organic semiconductor (OS) layer with a channel length of 8 µm was readily prepared without requiring the postbonding process in the conventional construction of microfluidic chips. Poly(3,4-ethylenedioxythiophene):poly(4-styrenesulfonate)/graphene quantum dots (PEDOT:PSS/GQDs) composites with different morphologies, such as microfilms, nanodendrites and nanowires were electropolymerized. The mass transfer process of the electropolymerization reaction was evidenced to be diffusion limited. Morphologies, growth directions, and chemical structures of OS layers could be tuned by the amplitude and the frequency of the AC voltage. Transfer and output characteristic curves of OECTs were measured on the microfluidic chip. The maximum transconductance, on/off current ratio and threshold voltage measured in the experiment was 1.58 mS, 246, and 0.120 V, respectively.
Tsinghua University Press
Jianlong Ji,Mangmang Li,Zhaowei Chen,Hongwang Wang,Xiaoning Jiang,Kai Zhuo,Ying Liu,Xing Yang,Zhen Gu,Shengbo Sang,Yang Shu, In situ fabrication of organic electrochemical transistors on a microfluidic chip. NanoRes.2019, 12(8): 1943–1951