采用超声分散和机械混合方法制备可打印的氧化石墨烯(GO)油墨,并利用3D打印技术和转印技术在聚二甲基硅氧烷(PDMS)基底上制备了多通道神经电极。结果表明:GO质量分数为7%时,油墨的黏度和储存模量最佳。在掺杂GO质量的50%的聚(3,4-乙烯二氧噻吩)-聚(苯乙烯硅氧烷)(PEDOT∶PSS)后,油墨的稳定性提高,电阻率下降了100倍。同时PEDOT∶PSS的引入提高了GO片层之间的结合力,避免了电极在干燥过程中的开裂。经过氢碘酸的处理后,电极的电阻率降低了近100倍,掺杂了PEDOT∶PSS电极的电荷储存容量增加了近1.7倍。在1kHz时的电化学交流阻抗由108Ω/cm2降低至70Ω/cm2。该研究为通道柔性神经电极的制备和打印油墨的设计提供了一个简单可行的方法。
A printable graphene oxide (GO) ink was prepared through ultrasonic dispersion and mechanical mixing methods,and multi-channel flexible nerve electrodes on the polydimethylsiloxanes (PDMS) substrate were fabricated via 3D-priting and transfer technology.The viscosity and storage modulus of GO ink was optimal when the GO mass fraction was 7%.After doping poly(3,4-ethylenedioxythiophene)-poly (styrene siloxane)(PEDOT∶PSS) with 50% of GO mass,the stability of the ink was improved and the resistivity decreased by 100 times.Furthermore,the addition of PEDOT∶PSS improved the bonding between the GO sheets and avoided the cracking of the electrodes during the drying process.After reduction treatment with hydriodic acid,the resistivity of the electrode was reduced by about 100 times and the charge storage capacity of the PEDOT∶PSS doped electrode increased by nearly 1.7 times.The EIS of electrode,at 1kHz,decreased from 108 Ω/cm2 to 70Ω/cm2.The research provided a simple and feasible method for the preparation of multi-channel flexible neural electrodes and the design of printing inks.
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基金资助
国家自然科学基金(52073057)
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