Nanoparticle engineering in perovskite solar cells for high-efficiency energy applications: A review

Engineering of nanoparticles is becoming a crucial approach for boosting the performance, stability, and functionality of perovskite solar cells (PSCs). Even though significant improvements have been achieved in the development of PSCs due to the high optical absorption, adjustable bandgaps, long carrier diffusion lengths, and ability to process at low temperatures, commercialization of PSCs is still hindered by moisture and heat sensitivity, degradation under UV illumination, ion mobility, interface recombination, lead issues, and scalability problems. This review discusses how engineering of nanoparticles including metal oxides, plasmonic metals, carbon nanomaterials, and up/down-conversion particles addresses such problems and makes possible fabrication of PSCs with efficiency over 20%. Instead of discussing nanoparticle types or particular device functionalities separately, we suggest a four-parameter approach to nanoparticle engineering based on the particle size, concentration, surface chemistry, and device position. Such an approach correlates nanoparticle design with charge extraction, defect passivation, optical management, protection from barriers, and heating control. We also discuss photovoltaic technologies comparison, PSC-battery combination, validation techniques, thermal management, and commercialization obstacles. In all reviewed works, the use of nanoparticles increases the efficiency relatively to bare devices by 3–27%, with oxide interfacial passivation and carbon barrier engineering being more scalable approaches.