Transient Cavitation Regulated Sonochemical Synthesis of Flexible Self-Supported Cuo@Pda/Cc Electrode for Highly Sensitive Glucose Sensor

Abstract

Transition metal oxides (TMOs) based self-supported electrodes have gained significant interest to develop high-performance electrochemical sensors and energy devices due to the abundant exposed catalytic site and low interface resistance. Among methods of fabrication for self-supported electrodes, sonochemical synthesis is recognized as a promising high-efficiency method for TMOs self-supported electrodes under mild conditions. However, it is still a challenge to obtain TMOs self-supported electrodes with well-controlled TMOs nanostructure and desirable interfacial properties via a sonochemical approach because of the uncontrollability of transient cavitation. In this study, CuO@polydopamine (PDA) nanoparticles (NPs) are in situ grown onto carbon cloth (CC) to fabricate CuO@PDA/CC self-supported electrode via a sonochemical process where transient cavitation intensity is regulated by sonopolymerized PDA. On the one hand, PDA can be utilized as the additive to stabilize and enhance the transient cavitation intensity within Cu 2+ containing solution to optimize the size and distribution of CuO@PDA NPs. On the other hand, PDA can also alter the growth of CuO NPs and enhance the interfacial binding of CuO@PDA NPs and CC due to the strong chelating ability between Cu 2+ and catechol groups from PDA. It is determined that the mean size of CuO@PDA NPs on the CuO@PDA/CC electrode is less than 100 nm with a narrow size distribution. Attributed to high electrochemical active surface area (4.61 mF cm -2 ) and low interface resistance (2.35 Ω), CuO@PDA/CC electrode displays excellent electrochemical performance as a glucose sensor with high sensitivity of 1.843 μA cm -2 mM -1 in a wide linear range up to 4.985 mM and excellent stability. This work provides a facile approach to fabricating the flexible self-supported electrodes with well-controlled nanostructure and desirable interfacial properties for high-performance electrochemical sensors via regulating the transient cavitation intensity in the sonochemical process.

Keywords: sonochemistry, transient cavitation, CuO, glucose sensor, self-supported electrode