Stable and Efficient Photo-Rechargeable Batteries Using Ruddlesden-Popper Perovskite-MoS₂ Hybrid Heterojunction

To minimize energy poverty at remote locations and run autonomous devices like IoT and smart city products, sustainable off-grid power solutions are required. Photo rechargeable batteries (PRBs) combine energy harvesting and energy storage technologies into a single device that offer a compact energy solution.^[1,2] We have shown a hybrid heterojunction based on (BA)₂(MA)₃Pb₄I₁₃ and MoS₂ nanoflakes for efficient Li-PRB application. Where BA and MA stand for CH₃(CH₂)₃NH₃⁺ and CH₃NH₃⁺respectively. The presence of MoS₂ in RP perovskite precursor solution triggered heterogeneous nucleation which results in the formation of heterojunction of type II. Such nucleation cause to improve structural, morphological, optical, optoelectronic, and ultimately photoelectrochemical properties of RP perovskite. The hybrid photodetector has shown 9.7 µAcm^-2transient photocurrent density at 0.0 V bias under Xe-lamp illumination (1 Sun) which are ~16 times higher as compared to its pristine material-based photodetector due to efficient extraction of electrons from perovskite to MoS₂.^[3]Such enhanced transient photocurrent density is beneficial to improve the photo conversion and storage efficiency (PC-SE) of hybrid Li-PRBs. Hybrid Li-PRB have demonstrated an average discharge specific capacities for three cycles from 128.66 mAhg^-1 to 180.67 mAhg^-1 (photo-enhanced: 40.42 %) at 64 mAg^-1, from 103.76 mAhg^-1 to 138.27 mAhg^-1 (photo-enhanced: 33.27 %) at 70 mAg^-1 under white LED illumination. The demonstrated Li-PRB is photo-charged to 1.3 V under 1 Sun illumination within ~ 1.63 hours and has shown PC-SE of ~0.52 % which outperforms other metal halide perovskite based PRBs.^[4] Finally, the scalability of these low-temperature solution processed hybrid photocathodes is demonstrated by fabricating a photo-battery module, comprising of three Li-PRB cells, which is operated between 5.00 V to 0.02 V at 68 mAg^-1 and shown photo-enhanced discharge time of ~ 74 %. The MoS₂ nanoflakes and RP perovskites based heterostructures based photoelectrodes can offer new avenues for the development of efficient and scalable photo-batteries.<br/><br/><b>References:</b><br/><br/>[1] Ahmad, S.; George, C.; Beesley, D. J.; Baumberg, J. J.; Volder, M. De. Photo-Rechargeable Organo-Halide Perovskite Batteries. <i>Nano Lett.</i> 2018, <i>18</i>, 1856–1862.<br/>[2] Tewari, N.; Shivarudraiah, S. B.; Halpert, J. E. Photorechargeable Lead-Free Perovskite Lithium-Ion Batteries Using Hexagonal Cs₃Bi₂I₉Nanosheets. <i>Nano Lett.</i> 2021, <i>21</i>, 5578–5585.<br/>[3] <b>Ansari, R. M.</b>; Salunke, A. D.; Rahil, M.; Ahmad, S. Strong Photocurrent from Solution-Processed Ruddlesden-Popper 2D Perovskite–MoS₂ Hybrid Heterojunctions. <i>Adv. Mater. Interfaces</i> 2023, <i>10</i>.<br/>[4] <b>Ansari, R. M.</b>; Chamola, S.; Ahmad, S. Ruddlesden–Popper 2D Perovskite-MoS₂ Hybrid Heterojunction Photocathodes for Efficient and Scalable Photo-Rechargeable Li-Ion Batteries. <i>Small</i> 2024, <i>2401350</i>, 1–13.