Multifunctional flexible perovskites with carbon nanotube/PC<inf>71</inf>BM stack for effective charge extraction and slow recombination phenomena

Definitely not a hyperbole that perovskites have been distinguished in championing revolution of energy harvesting. The development of extremely effective perovskite devices is the focus of extensive and rigorous research efforts. The photo-physics mechanism, device architectures, processing methods, and characterizations could all be considered subcategories of these efforts. On either side of the perovskite absorbers, appropriate charge transport layers are critical for optimizing the overall device efficiency. They also facilitate discrepancies between the charge extraction and recombination phenomena. Despite their prominence, research on the charge transfer kinetic mechanisms and underlying dynamics has lagged. To precisely follow the kinetics of an extensive process by holding distinct and energetically confined spectrum properties, we have here addressed the fundamental challenges using a thin charge extraction layer made of semiconducting single walled carbon nanotubes (SWCNT). Here, the hole transport component is fullerene. By filling in pinholes and vacancies between perovskite grains, PC71BM ([6,6]-phenyl-C71-butyric acid methyl ester) specifically plays a key role in enhancing the characteristics of the light-absorbing layer and developing a film with large grains and reduced grain boundaries. This design demonstrated increased electrical parameters with better efficiency of about 13.41%. The CNT/PCBM regions had the maximum open circuit voltage V OC, which was around 0.71 V, with short circuit current density J SC values of 16.60 mAcm−2 and fill factor of 64.03% along with better stability. Further, the frequency responses of the harvesting system with perovskite materials under harmonic excitation are derived and presented to analyze the mechanical behavior and piezo behavior proving the perovskites to be multifunctional.