微通道电化学反应器具有电极间距小、比表面积大，能够强化传质、传热且安全高效等优点，是有机电合成的关键装备之一。阴极析氢反应是电化学有机合成的共性过程之一，其传递和反应规律在电化学反应装备的设计和应用中至关重要。当前，针对微通道内电化学析氢反应的多相流行为及其影响规律的研究鲜有报道，围绕微通道内H2气泡的形成和演变规律的研究有助于指导微通道电化学反应器的开发和运用。基于此，本文以苯甲醇的电化学阳极氧化和阴极析氢反应作为有机电合成的代表性体系，针对微通道内电极表面气泡的产生和运动行为开展系统研究，揭示了微通道内电解气泡的形成机制和气液两相流动行为对反应过电位的影响规律，为电化学微反应技术的开发提供基础。针对微通道内电解气泡的产生过程，设计了以针状电极为核心的可视化微通道电化学反应器，认识了气泡在微电极表面周期性形成引起的反应电位周期性变化规律，阐明了“山峰”型和“平台”型两种电压波形的形成机制。探索了微通道内剪切流速、外加电流、反应物浓度等因素对气泡脱离尺寸和电压波动的影响，以毛细管准数为基础，建立了气泡脱离尺寸的数学模型。揭示了电压振幅与气泡脱离尺寸间的线性关系并建立关联式，发现气泡产生主要诱导活化过电位和欧姆过电位发生改变，通过电极间距实验设计初步揭示了本实验中活化过电位和欧姆过电位各占50%的贡献率。针对微通道内电解气泡运动过程，设计了含有多组平行电极的可视化玻璃微通道装置，发现气泡在电极表面的流动同样会造成电压周期性波动的现象，揭示在气泡的长轴达到电极长度的5.4倍时，电极反应因离子传输通道被阻断而无法继续的控制规律。探索了微通道内气泡分散尺寸、物料流速、反应电流、反应物浓度等因素对反应电压波动的影响，结果表明气泡引起的电阻增量与气泡半周长和电极间距差值ΔL呈现线性关系。控制微通道内气泡以小于电极间距的尺寸通过电极有利于大幅降低反应过电位，使电化学反应稳定、高效进行。

The microchannel electrochemical reactor has the advantages of small electrode spacing, large specific surface area, enhanced mass transfer, heat transfer, safety and high efficiency, and is one of the key equipment for organic electrosynthesis. Hydrogen evolution reaction at the cathode is a common process in electrochemical organic synthesis, and its transfer and reaction behavior are crucial in the design and application of electrochemical reaction equipment. However, there are few reports on the multiphase flow behavior and its influence on the microchannel electrochemical hydrogen evolution reaction. Therefore, studying the formation and evolution of H2 bubbles in microchannels can guide the development and application of microchannel electrochemical reactors. Based on the representative system of electrochemical oxidation of benzyl alcohol and cathodic hydrogen evolution reaction, this study systematically investigates the formation and movement behavior of gas bubbles on the electrode surface inside microchannels. The study reveals the formation mechanism of electrolysis bubbles in microchannels and the influence of two-phase flow behavior on overpotential, providing a foundation for the development of electrochemical microreaction technology.Aiming at the generation process of electrolytic bubbles in the microchannel, a visualized microchannel electrochemical reactor with needle electrodes as the core was designed. The periodic variation of the reaction potential caused by the periodic formation of bubbles on the surface of the microelectrode was recognized, and the formation mechanisms of the "peak" and "plateau" voltage waveforms were clarified. The effects of factors such as shear flow rate, applied current, and reactant concentration in the microchannel on the size of the bubble detachment and voltage fluctuation were explored, and a mathematical model of the size of the bubble detachment was established based on the capillary standard number. The linear relationship between the voltage amplitude and the detachment size of the bubbles was revealed and a correlation was established. It was found that the generation of bubbles mainly induced changes in the activation overpotential and the ohmic overpotential. And through the design of the electrode spacing experiment, it is revealed that the activation overpotential and the ohmic overpotential each account for 50% of the contribution rate. Regarding the movement process of electrolysis bubbles inside microchannels, a visualization glass microchannel device containing multiple sets of parallel electrodes was designed. The phenomenon of periodic voltage fluctuation caused by the flow of bubbles on the electrode surface was observed. It was found that when the long axis of the bubble reaches 5.4 times the electrode length, the reaction of the electrode is blocked due to the blockage of ion transfer channels. The effects of bubble dispersion size, material flow rate, reaction current, and reactant concentration inside microchannels on voltage fluctuation were explored. The results show that the resistance increase caused by the bubbles is linear with the difference between the half circumference of the bubbles and the difference between the electrodes. Controlling the size of the bubbles inside microchannels to be smaller than the electrode spacing is conducive to significantly reducing the overpotential of the reaction, making the electrochemical reaction stable and efficient.