Efficiency - Page 2

Researchers at Japan's National Institute of Advanced Industrial Science and Technology (AIST) and the UK's University of Oxford have asserted that while perovskite-on-silicon tandem solar cells are highly promising, the intrinsic multilayer device design presents challenges in complexity, which can be a drawback in future mass production. To this end, they developed a TiO_x layer (∼3–5 nm) grown by atomic layer deposition (ALD), that enables a series interconnection of a perovskite n-i-p top cell with a silicon wafer directly. 

A photo of the tandem solar cell fabricated on a 25 mm × 25 mm Si substrate. Image from: Small

The TiO_x layer serves as an all-in-one interconnect, fulfilling the functions of silicon surface passivation, hole extraction from silicon, and recombination junction at the top/bottom cell interface. As a result, a proof-of-concept 22.4%-efficient tandem device was demonstrated. Furthermore, an improved PCE of 26.5% was achieved by capping the TiOx with a thin ALD-TiNy layer (∼4 nm). 

Researchers at Tokyo City University recently developed flexible perovskite/silicon tandem solar cells by fabricating perovskite solar cells atop bendable thin-crystalline silicon solar cells. By reducing the thickness of the silicon substrate to approximately 60 µm, applying microtexturing to its surface, and incorporating a low-refractive index-doped layer, the team produced a flexible silicon heterojunction solar cell with an efficiency exceeding 21%. 

Subsequently, by optimizing the self-assembled monolayer processing conditions on the microtextured surface and constructing an inverted perovskite solar cell on the flexible SHJ, they achieved 26.5% efficiency for the flexible perovskite/silicon tandem solar cell. 

Ultraviolet (UV)-induced damage and limited solar spectrum utilization can hinder the performance of perovskite solar cells (PSCs). In a recent study, researchers from Fuzhou University and Chinese Academy of Sciences developed a thermally activated delayed fluorescent (TADF) molecule, 4CzIPN, to address these challenges. 

Acting as a down-conversion agent, 4CzIPN can convert UV light to visible light via Förster energy transfer, enhancing light absorption and reducing photon loss. Additionally, it can bind Pb²⁺ defects and prevents organic cation degradation through cationic π-effects, stabilizing the perovskite structure. By serving as a crystal growth site, 4CzIPN can promote intermediate phase formation and delay the crystallization process, and improve film quality while mitigating residual stress due to its high thermal expansion coefficient. Furthermore, its UV filtration and hydrophobic properties would reduce perovskite decomposition and device degradation.

Global giant BOE has updated on progress in its perovskite business during its 2024 earnings briefing. 

Key milestones include:

• Achieving 26.3% efficiency on 25 × 25 mm lab-scale cells (March 2025)
• Reaching 20.79% on 300 × 300 mm cells via a pilot line launched in May 2024;
• Hitting 17.52% efficiency on 1.2 × 2.4 m modules from a semi-industrial line launched in Sept. 2024, setting a record for the largest-area, highest-efficiency reported perovskite module to date.
• In March, Chinese smartphone manufacturer Infinix released the world’s first solar-charging smartphone using BOE’s advanced perovskite technology. BOE disclosed that this product is still in R&D at present.

Perovskite solar company SolaEon Technology has announced that its all-perovskite tandem solar cell achieved a certified conversion efficiency of 31.38%, with a stabilized MPPT efficiency of 30.7%.

Solaeon states that this sets a new global record for this cell type and that its tandem cell efficiency has risen from 29.34% in 2024 to 31.38%.

Researchers from Wuhan University, South China Normal University and Chinese Academy of Sciences (CAS) have  explained that while all-perovskite tandem solar cells (TSCs) offer exceptional performance and versatile applicability, a significant challenge persists in bridging the power conversion efficiency (PCE) gap between small- and large-area (>1 cm²) devices, which presents a barrier to the commercialization of all-perovskite TSCs. 

Now, the team introduced a specialized crystal-modifying agent, piracetam, tailored for wide-bandgap perovskites, homogenizing top wide-bandgap subcells and enabling the construction of efficient large-area TSCs. 

Scientists at the Chinese Academy of Sciences (CAS), Xuancheng Kaisheng New Energy Technology Company and Tianjin Institute of Power Sources have found a way to make flexible tandem solar cells more efficient and durable by enhancing the adhesion of top layers to the bottom layers of the cell.

Copper indium gallium selenide (CIGS) is a commercial semiconductor known for its outstanding adjustable bandgap, strong light absorption, low-temperature sensitivity, and superior operational stability, making it a promising candidate for bottom-cell use in next-generation tandem solar cells. Flexible perovskite/CIGS tandem solar cells combine a top layer of perovskite with a bottom layer of CIGS. This tandem cell holds great potential for lightweight, high-efficiency applications in the photovoltaic field but the rough surface of CIGS makes it difficult to produce high-quality perovskite top cells on top, which limits the commercial prospects of these tandem cells.

Researchers at Queensland University of Technology (QUT) have developed an eco-friendly method to fabricate perovskite solar cells (PSCs) by incorporating a fluoride additive into a water-based solution. This approach eliminates the use of toxic solvents typically required in PSC production, while achieving power conversion efficiencies above 18%.

The team introduced lead(II) fluoride (PbF₂) into the water-based precursor solution to regulate crystal growth dynamics and improve film quality. The fluoride additive accelerated the formation of the photoactive phase and promoted the crystallization orientation, both critical for efficient solar energy conversion.

LONGi has once again announced a new efficiency record for its proprietary dual terminal perovskite-silicon tandem solar cell - 34.85%, certified by the US National Renewable Energy Laboratory (NREL).

LONGi’s research team is on a roll. In November 2023, they increased cell efficiency to 33.9%. Then, in June 2024, they pushed it up to 34.6%. And now, in less than a year, they’ve catapulted it to 34.85%.

Researchers at The University of Queensland have reported a 'new world record efficiency for lead-free perovskite solar cells'.

A team led by Professor Lianzhou Wang, based at the Australian Institute for Bioengineering and Nanotechnology (AIBN) and the School of Chemical Engineering, achieved a breakthrough certified efficiency of 16.65% using tin-based perovskite - a non-toxic alternative to the lead typically used in next-generation solar cells.