July 2026

TandemPV has installed one of its perovskite-silicon tandem panels atop UC Merced's Science and Engineering 2 Building for outdoor testing, installed alongside smaller Tandem PV test panels already in place, marking the start of a multi-month durability study run with UC Merced researchers.

The panel is built on Tandem PV's approach of integrating a perovskite layer into existing silicon solar manufacturing supply chains. A coating just one-hundredth the thickness of a human hair is meant to boost the panel's energy output from 24% to 30%, which the company says translates to about 30% more electricity from the same footprint compared with a typical silicon panel. Because labor and balance-of-system costs account for roughly 75% of utility-scale solar costs, generating more power per panel without a larger footprint helps bring down the overall cost of a solar installation.

Researchers from Nanjing University, JA Solar, Chongqing University, Jiangsu New Energy Development Co. and Jiangsu Guoxin Research Institute have designed a new self-assembled monolayer (SAM) additive molecule that fixes a longstanding defect problem at the buried hole-transport interface of inverted perovskite solar cells, enabling a wide-bandgap perovskite cell with a champion power conversion efficiency (PCE) of 23.7% and a perovskite/silicon tandem device that reaches 33.3% (certified at 33.1%), with no measurable PCE loss after 30 days of outdoor operation.

Device configuration illustration and chemical structures of Me and TTA. Image from: Science Advances

In inverted perovskite solar cells, the SAM sitting beneath the perovskite layer governs how well the perovskite crystallizes and how efficiently charge is extracted at that buried interface. The carbazole-based SAM molecule Me-4PACz is widely used for its strong hole-extraction properties, but it tends to self-aggregate when processed from alcoholic solvents, producing uneven coverage with island-like clusters and pinholes. That patchy coverage weakens binding to both the substrate below and the perovskite above, raises interface defect density, and impairs charge transport - a problem that has proven difficult to solve without sacrificing some other aspect of performance.

Researchers from Tsinghua University and Civil Aviation University of China have developed a perovskite laser cell-thermoelectric (PLC-TE) tandem device that converts an incoming green laser beam into electricity at a power conversion efficiency (PCE) of 38.49%, designed to be embedded in the wing of an unmanned aerial vehicle (UAV) as an in-flight power source.

The work targets laser wireless power transmission (LWPT), an approach to beaming energy over long distances that offers strong directionality, flexible beam-steering and resistance to electromagnetic interference. For UAVs, whose flight time is fundamentally capped by onboard battery capacity, LWPT raises the possibility of a drone that recharges continuously in the air rather than returning to the ground. CsPbBr₃ perovskite is a strong candidate receiver material for this application: its broad bandgap absorbs efficiently across the blue-green range (400-550 nm) that aligns with atmospheric transmission windows, and the material remains stable under the high-temperature, high-energy-photon conditions a concentrated laser beam produces.

With just a few months to go until Perovskite Connect 2026, returning once again to Berlin for its second edition, we are revisiting some of the standout talks from the 2025 edition. These videos feature three companies working at the leading edge of commercializing perovskite and perovskite-silicon tandem solar panels. Each short clip runs one to two minutes and offers a taste of the full presentations delivered on stage in Berlin.

Oxford PV - Ed Crossland: "The Era of Perovskite-on-Silicon: Delivering Commercial 30%+ Modules to the Global Market"

Silicon solar is nearing its practical efficiency limit, and perovskite-silicon tandems are the technology poised to break through it. In this keynote, Oxford PV's Ed Crossland reflected on the company having shipped the world's first commercial perovskite-silicon tandem modules in 2024, and charted the roadmap toward higher efficiencies - with a particular emphasis on durability, scalability, and integrating perovskite cells into existing silicon manufacturing lines with minimal disruption.

Researchers from Taiwan's National Yang Ming Chiao Tung University and Flexwave have developed a self-adaptive interfacial nanostructure (SAIN) for the hole-extraction contacts of inverted perovskite solar cells, reporting a power conversion efficiency (PCE) approaching 20% under standard 1-sun illumination and 38.16% under indoor lighting at 2,000 lux - a figure that climbs above 40% once paired with an optical enhancement film, placing the device among the most efficient indoor perovskite solar cells reported to date.

The team explains that "regular" n-i-p configurations tend to reach higher efficiencies, but inverted PeSCs offer better long-term stability and are easier to stack into multijunction devices, making the p-i-n architecture an attractive target for further improvement. A major bottleneck in inverted PeSCs is the buried hole-transport layer (HTL) sitting beneath the perovskite film. Because the perovskite crystallizes directly on top of it, the HTL's quality shapes both the interface and the growing perovskite layer itself, and a poor HTL drives up non-radiative recombination - carriers lost to defects rather than converted into current, which shows up as low photoluminescence quantum yield in the finished film. Today's leading inverted devices typically grow their perovskite on either a hole-conducting polymer such as poly(triarylamine) (PTAA) or a self-assembled monolayer (SAM) built from carbazole-based molecules. Each has drawbacks: high-quality PTAA is costly to produce, while SAMs are difficult to deposit as a conformal, densely packed layer, which hurts device-to-device reproducibility. Both materials are also hydrophobic, complicating full-coverage perovskite deposition over large areas. Hybrid PTAA-plus-SAM contacts have been explored to combine their strengths, but so far only for standard 1-sun operation, leaving their potential for indoor photovoltaics untested.

Researchers from Soochow University, The Hong Kong Polytechnic University, Suzhou Maxwell Technologies, the University of Oxford, Wuxi EliTe Solar, Hangzhou Zhongneng Photoelectricity Technology, Shenzhen Polytechnic University and Suzhou National Laboratory have developed an indium-free recombination layer for monolithic perovskite/silicon tandem solar cells, based on titanium oxynitride (TiOxNy), reporting power conversion efficiencies of 33.3% on 1.0 cm² devices and 30.6% on industrial-size, 207.87 cm² tandems.

Monolithic perovskite/silicon tandems are widely seen as a route past the efficiency ceiling of single-junction photovoltaics, but turning lab-scale records into durable, manufacturable modules depends heavily on one thin layer: the recombination interconnect that joins the two subcells. That layer has to do three things at once - support fast charge recombination, stay optically transparent so light reaches both subcells, and form a chemically robust interface that holds up over time. Today's leading options each fall short somewhere: indium-containing transparent conductive oxides (TCOs) raise cost and supply concerns, while silicon-based tunnel junctions introduce parasitic optical losses.

Researchers from Nanjing Tech University have developed a vacuum-deposition strategy that improves the performance of fully evaporated perovskite solar cells (PSCs) by precisely controlling the solid-state reaction pathway during film formation.

Vacuum deposition is widely viewed as a scalable and solvent-free alternative to solution processing, with potential advantages for industrial integration. However, devices fabricated using this approach have historically lagged behind their solution-processed counterparts due to defects formed during crystallization. The Nanjing Tech team addressed this limitation by introducing formamidinium acetate as a reactive precursor that fundamentally alters how the perovskite phase forms.

Researchers from the Skolkovo Institute of Science and Technology, ITMO University, HSE University and Lund University have demonstrated a perovskite laser diode that lases under a steady direct current, without relying on epitaxial growth - a long-sought result that has repeatedly eluded the field.

Halide perovskites have been an attractive candidate for electrically driven microlasers for years, mainly because of how well they perform under optical excitation. Single-crystal cavities and solution-assembled microstructures made from these materials have repeatedly delivered low lasing thresholds when pumped with light. Getting the same devices to lase from direct electrical injection - with electrons and holes fed straight into the perovskite - has proven far harder, and a true, directly electrically pumped perovskite laser diode had not been demonstrated.

Researchers from China's Northwestern Polytechnical University and Shaanxi Joint Laboratory of Graphene (NPU) and Southern University of Science and Technology have developed a new interfacial strategy that addresses a stubborn weak point in inverted perovskite solar cells (PSCs): the instability of the fullerene (C60) electron transport layer.

C60 and its derivatives are popular choices for electron transport layers in inverted PSCs thanks to their high electron mobility and favorable energy-level alignment with the perovskite, but suffer from intrinsic drawbacks. Its electronic disorder promotes trap-assisted recombination, which narrows the quasi-Fermi level splitting and drags down the open-circuit voltage. Just as importantly, C60's high molecular symmetry and weak intermolecular bonding make it prone to thermodynamically driven aggregation as the film forms - which worsens under light and heat. As the fullerene agglomerates, contact across the perovskite/C60 interface deteriorates, interface resistance climbs, charge transport suffers, and the device degrades faster. Functionalized C60 derivatives can improve compatibility and morphology, but the added groups often leave the material even more vulnerable to stress-induced breakdown. To break this cycle, the team designed an acceptor-donor-type metallopolymer, "polycarbolong," and used it to build what they call a corrugated polycarbolong interlocking (CPI) layer at the interface. 

Chinese solar module manufacturer GCL System Integration Technology (GCL SI) has announced a certified power conversion efficiency of 33.44% for its self-developed flexible perovskite-silicon tandem solar cell. The result was verified by the China National Center of Inspection on Solar Photovoltaic Products Quality (CPVT).

GCL SI’s flexible perovskite-silicon tandem solar cell. Image Credit: GCL SI

Developed jointly with Soochow University, the cell also achieved a device-level power-to-weight ratio exceeding 2,000 W/kg. GCL SI said its research team produced lightweight, bendable cells that resist fracture by overcoming several challenges in ultra-thin silicon substrate integration, interface passivation, and flexible stress control.