Researchers at North Carolina State University and Brookhaven National Laboratory have reported a technique for engineering layered hybrid perovskites (LHPs) down to the atomic level, which enables precise control on how the materials convert electrical charge into light. 

Image credit: Matter

The technique opens the door to engineering materials tailored for use in next-generation printed LEDs, lasers and photovoltaic devices.

Interface engineering plays a significant role in the constant improvement in the performance of perovskite photovoltaics, but such devices still suffer from several issues, including unavoidable open circuit voltage (VOC) losses. Now, an international team of researchers from Università Degli Studi Di Pavia, King Abdullah University of Science and Technology (KAUST), Chinese Academy of Sciences (CAS), University of Cambridge, Istituto Italiano di Tecnologia (IIT), Slovak Academy of Sciences and Imperial College London have proposed a different approach by creating a photo-ferroelectric perovskite interface. 

Graphical representation of the 2D/3D/2D perovskite heterostructure. Image from: Nature Communications

By engineering an ultrathin ferroelectric two-dimensional perovskite (2D) which sandwiches a perovskite bulk, the scientists exploited the electric field generated by external polarization in the 2D layer to enhance charge separation and minimize interfacial recombination. As a result, they observed a net gain in the device VOC reaching 1.21 V, the highest value reported to date for highly efficient perovskite PVs, leading to a champion efficiency of 24%. 

As an increasing amount of multimodal sensors are used in intelligent electronics, energy expenditure gets more massive. Consequently, researchers aim to develop efficient computing paradigms or integrate energy harvesting from ambient sources. Halide perovskites possess unique photophysics and coupled ionic-electronic dynamics that actualize memory devices for brain-inspired computing. Synergizing the computing capability with their conventional light harvesting efficacy could address this issue. 

Researchers from Singapore's Nanyang Technological University and Hong Kong's City University of Hong Kong recently examined the use of halide perovskite photovoltaics for in-sensor reservoir computing (RC). 

Two-dimensional Ruddlesden-Popper (2DRP) phase perovskites have excellent long-term environmental and structure stability. However, the efficiency of 2DRP perovskite solar cells (PSCs) still lags behind that of their 3D counterparts due to the large exciton binding energy between the large-volume organic spacer and the inorganic plate compared to their 3D analogs.

To address this issue, researchers from China's Northwestern Polytechnical University and Xijing University have used a thin layer of self-assembled monolayer material between the transporting layer and the perovskite film for efficient and stable 2DRP-based PSCs. 

Reports suggest that RenShine Solar has completed the construction of its 1.2 MW perovskite rooftop distributed power station. The plant is reportedly generating power and was connected to the grid on September 29. 

The company says the plant’s power generation exceeded 3,000 kWh/day on its first day. 

It was reported that SolaEon Technology, a Chinese manufacturer of next-gen solar cells with a focus on perovskite-based PV, recently signed an investment contract with the local government of Xuzhou City, China, as one of fifty-six contracts signed at the 27th Xuzhou Trade and Investment Fair.

SolaEon plans to invest about 1.2 billion yuan (almost USD$170 million) in the perovskite solar cell production base in the High-Tech Zone. Upon completion of the production lines with an annual capacity of 200MW and 1GW of perovskite cells, the production value is expected to reach 2 billion yuan (approximately USD$283 million) per year.

Slot-die coating (SDC) technology is a potential approach to mass produce large-area, high-performance perovskite solar cells (PSCs) at low cost. However, when the interface in contact with the perovskite ink has low wettability, the SDC cannot form a uniform pinhole-free perovskite film, which reduces the performance of the PSC.

Optimizing Slot-Die Coating for Commercial Solar Cell Production. Image credit: InfinityPV

Researchers from Korea's Jeonbuk National University have examined the correlation between interfacial roughness, wettability, and the overall efficiency of perovskite solar cells produced using slot-die-coating. This work offers a comprehensive understanding of how modifying the roughness of the hole transport layer (HTL) can improve the quality of perovskite films, enhance charge transport, and ultimately lead to high-efficiency perovskite solar cells with long-term stability.

Researchers from NingboTech University, Hunan Institute of Engineering, Hangna Nanofabrication Equipment Co. and University Malaysia Sabah have developed an inverted perovskite solar cell with an interface passivator based on lead carbanion (Pb–C^–), that reportedly achieved the highest open-circuit voltage ever recorded for an inverted perovskite PV device. The lead carbanion layer was responsible for reducing defects at the interface between the perovskite layer and the electron transport layer.

Inverted perovskite cells, or “p-i-n” cells, have the hole-selective contact p at the bottom of intrinsic perovskite layer i with electron transport layer n at the top. Conventional halide perovskite cells have the same structure but reversed – a “n-i-p” layout. In a n-i-p architecture, the solar cell is illuminated through the electron-transport layer (ETL) side; in the p-i-n structure, it is illuminated through the hole‐transport layer (HTL) surface. Inverted perovskite solar cells are known for their impressive stability but have been held back by relatively low efficiencies. This issue mainly arises at the point where the perovskite layer meets the electron transport layer, causing energy loss instead of being converted into useful power, primarily caused by carrier recombination, especially at the interface between perovskite and the electron transport layer.

Researchers from Chungnam National University and Russian Academy of Sciences have reported a method to increase the efficiency of perovskite solar cells (PSCs) by modifying the surface of a fluorine-doped indium tin oxide (FTO) substrate using an atmospheric pressure plasma treatment. 

The surface modification of the FTO film involved several challenges, such as control of the blocking layer uniformity, removal of pinholes, and deposition of a dense layer. This strategy allows the suppression of charge recombination at the interface between the FTO substrate and hole conductor. 

The U.S. Department of Energy (DOE) Solar Energy Technologies Office (SETO) Small Innovative Projects in Solar (SIPS) 2024 funding program provides $5.4 million for seedling R&D projects that focus on innovative and novel ideas in photovoltaics (PV) and concentrating solar-thermal power (CSP) and are riskier than research ideas based on established technologies.

The 16 selected projects were recently announced, among them were 5 perovskite-related projects.