High-performance planar micro-supercapacitor arrays for integrated photo-detecting systems

Thin-film based micro-supercapacitors (TF-MSCs) have generated an increasing interest owing to their suitability for integration as energy storage devices in the flexible and wearable electronics, especially in equipment for personal health monitoring or real-time environmental detection. However, the differences in fabrication of energy storage and detecting units make the preparation for these integrative devices more complicated, and also limit the choice of materials. Here, an integrated photo-detecting device driven by an interdigital TF-MSC array is fabricated, in which Sb₂S₃ is both utilized to detect visible light and to generate energy thus breaking this restriction. The TF-MSC, with the Sb₂S₃@polyaniline (PANI) films in-situ deposited as the negative electrode and activated carbon as the positive electrode, achieves a capacitance of 18.44 mF cm⁻² at 0.25 mW cm⁻² and retains 97% of capacitance after 7000 cycles at 1 mA cm⁻² with unvaried coulombic efficiency. Based on the scalable and editable Sb₂S₃@PANI films, the single TF-MSC is extended to the in-plane integrated TF-MSC array, which shows redoubled potential windows and practical applications. The vertical or lateral Sb₂S₃ based photodetector, which is integrated with a TF-MSC array on the same substrate, obtains a quick response under a wide range of light intensities. This integrated photodetector powered by a TF-MSC array proves the application potential in portable monitoring equipment.