Advanced MASnI₃ and PTAA-Integrated ZnO₂ Perovskite Composite: Optimizing Stability and Charge Dynamics for Next-Gen Photobatteries

To advance off-grid energy solutions, developing flexible photobatteries capable of direct light charging is essential. This study presents an innovative photobattery architecture that incorporates zinc oxide (ZnO₂) as an electron-transporting and hole-blocking layer, combined with a hybrid methylammonium tin iodide composite with poly-triarylamine (MASnI₃/PTAA) for light absorption and hole transport. PTAA facilitates efficient hole transport to the anode, thereby enhancing charge separation and reducing recombination losses. The MASnI₃ perovskite serves as an effective sunlight absorber, generating charge carriers. ZnO₂, known for its high chemical stability and rapid electron mobility, effectively blocks holes and ensures swift electron flow to the cathode, which optimizes the overall charge transfer dynamics. This refined structure achieves a photoconversion efficiency enhancement of up to 0.53% and retains approximately 98% of its capacity after 700 cycles. The optimized MASnI₃/PTAA/ZnO₂ photobattery demonstrates a 3-fold reduction in light charging time, positioning it as a strong candidate for practical, light-rechargeable energy storage applications.