Efficiency - Page 32

Researchers from the University of Rome Tor Vergata's Centre for Hybrid and Organic Solar Energy (CHOSE), IMEC and EPFL have reported on a solar module with an efficiency of 20.72%, based on tin oxide (SnO₂) as an electron transport layer, an organometal halide perovskite layer, organic halide salt phenethylammonium iodide (PEAI) as a passivation agent, and Spiro-OMeTAD as the hole transport layer (HTL).

The international research team presented its low-temperature planar perovskite module with an n'i'p architecture, an aperture area of 11'cm², and a geometrical fill factor of 91%.

Researchers from the University of Toronto and their international collaborators have leveraged quantum mechanics to optimize the active layer within an inverted perovskite solar cell.

"Perovskite crystals are made from a liquid ink and coated onto surfaces using technology that is already well-established in industry such as roll-to-roll printing," says Hao Chen, a post-doctoral researcher in Sargent's lab and one of four co-lead authors of a new paper published in Nature Photonics. "Because of this, perovskite solar cells have the potential to be mass produced at much lower energy cost than silicon. The challenge is that right now perovskite solar cells lag traditional silicon cells in stability. In this study, we aimed to close that gap."

A research team, led by Professor Ivan Mora Ser from the Institute of Advanced Materials (INAM) of the Universitat Jaume I of Castell, has improved the efficiency and durability of tin perovskite solar cells. The cells presented in the recent study exceeded 1,300 hours of operational stability, thanks to the incorporation of additives in the preparation of the devices.

Tin-based halide perovskites are being studied as potential candidates for lead-free perovskite solar cells. In the case of tin, an efficiency of more than 14% has been achieved so far, but it has major stability problems. This new work has introduced a combination of dipropylammonium iodide and sodium borohydride, two additives that have made it possible to prepare devices with PCEs of more than 10%, which boast greater stability and have maintained 96% of the initial PCE after 1,300 hours under solar illumination in a nitrogen atmosphere.

Researchers from solar manufacturer Hanwha Q CELLS and research institute Helmholtz-Zentrum Berlin (HZB) have announced a power conversion efficiency of 28.7% for a two-terminal perovskite-silicon tandem solar cell.

The device is based on a silicon bottom cell relying on Hanwha Q CELLS' monocrystalline Q.antum half cell technology and a perovskite-based top cell.

An international research group has designed a semi-transparent perovskite solar cell that reportedly shows an improved open-circuit voltage and fill factor thanks to plasmonic enhancement.

The technique is based on the enhancement of the cell's electromagnetic field through metal nanostructures, which improves the device's low optical absorption in the visible spectrum. The research team designed the tech with applications in building-integrated photovoltaics (BIPV) in mind, but it can also be suitable for automotive and smart glasses.

Researchers from France's Institut Photovoltaïque d'Île-de-France (IPVF), EDF R&D and C2N have fabricated a mini perovskite solar module, via deposition of tin oxide as an electron extraction layer using chemical bath deposition (CBD), a low-cost and solution-based fabrication process.

Using this simple low-temperature deposition method, highly homogeneous SnO₂ films can reportedly be made in a reproducible manner. In addition, the perovskite layer was prepared by sequentially slot-die coating on top of the n-type contact. The symbiosis of these two industrially relevant deposition techniques can allow for the growth of high-quality dense perovskite layers with large grains.

Researchers from Germany's Helmholtz-Zentrum Berlin (HZB) and Institute for Solar Energy Research (ISFH) have reported that passivated emitter and rear cell (PERC) tech can be suitable as a basis for tandem cells with perovskite top cells.

PERC cells are usually used in mass production of silicon solar cells, and while the efficiency of the study's tandem cells is still below that of optimized PERC cells alone, the team estimates that it could be increased to up to 29.5% through targeted optimization.

Researchers from the Wuhan Institute of Technology and Wuhan University have investigated key factors for realizing high-performance narrow-bandgap Pb-Sn perovskite solar cells (PSCs) via numerical simulations.

The team studied both extrinsic and intrinsic factors of efficient narrow-bandgap Pb-Sn perovskite solar cells. The effects of extrinsic factors on device performance predicted that a p-i-n structure along with appropriate charge transport layers is superior to an n-i-p structure, benefiting from a better energy band alignment. The key intrinsic factors that were studied demonstrated that surface defect density, body defect density, and film thickness of perovskite absorbers play a pivotal role in determining device performance.

Researchers at the University of Rome Tor Vergata's Centre for Hybrid and Organic Solar Energy (CHOSE), collaboration with Greatcell Solar Italy, Technische Universität Dresden and Istituto di Struttura della Materia (ISM-CNR), have designed a way to reduce cell-to-module losses in perovskite solar modules, by optimizing the laser design, establishing a relationship between geometrical fill factor, cell area width, and P1'P2'P3 laser parameters.

In their new work, the research team presented a complete assessment of the optimization of the laser and design of perovskite solar modules. They also transferred these optimizations to a minipanel size, proving the durability of the process.

It was recently reported that Chinese researchers from the ECNU and the Ningbo Institute of Materials Technology and Engineering under the Chinese Academy of Sciences were successful in developing a type of perovskite solar cell (PSC) with high power conversion efficiency.

PSCs can be generally classified into two categories, n-i-p devices and inverted p-i-n devices. The p-i-n PSCs can be produced at low temperature with good stability, and are compatible with crystal silicon cell to achieve the development of laminated cell, said Fang Junfeng, professor at the East China Normal University (ECNU). At present, the efficiency of n-i-p perovskite cells has reached 25%, while the maximum efficiency of inverted p-i-n devices remains at 22%-23%.