The electrochemical conversion and storage of renewable energy present substantial potential as a sustainable alternative to conventional fossil fuel energy systems. This approach not only supports the transition to cleaner energy but also enhances energy security and promotes environmental sustainability. Central to this field is electrocatalysis, which facilitates the transformation of reactants into high-value chemicals and relies on the efficiency of catalytic processes. The increasing interest in electrocatalytic activity is simulated by advances in catalyst design and mechanistic understanding. However, traditional electrochemical techniques often fall short in uncovering the distinct properties of nanomaterials. Recent advancements in physical nanoelectronic devices indicate that the application of small-scale devices in electrocatalysis offers a promising and innovative solution. These innovative devices enable precise electrochemical investigations by employing individual nanowires or nanosheets as working electrodes, thereby providing multi-dimensional insights into electrochemical interfaces. This review presents recent advancements in on-chip microdevices, emphasizing their significant developments in energy conversion and storage technologies. It highlights the critical role of micro-devices in fostering future innovations and enhancing their applications within the energy sector.