Researchers from China's Shenzhen University of Information Technology, Handan Polytechnic College and Harbin Institute of Technology have developed a new strategy to improve the performance of two-dimensional (2D) perovskite solar cells by introducing diethylammonium (DEA⁺) as a spacer cation, addressing the long-standing trade-off between stability and efficiency in these materials.

2D perovskites are seen as a promising alternative to their 3D counterparts due to their enhanced environmental stability, which originates from the incorporation of bulky organic spacer cations between inorganic layers. These spacers act as barriers against moisture and oxygen ingress, but they typically introduce insulating characteristics that hinder charge transport and reduce crystallinity. As a result, while 2D perovskites have achieved power conversion efficiencies (PCEs) up to 19.41%, further improvements are constrained by limited carrier mobility and suboptimal film quality. In this work, the researchers replaced the commonly used phenylethylammonium (PEA⁺) spacer with DEA⁺ in layered perovskite structures of the form A'₂MAₙ₋₁PbₙI₃ₙ₊₁, focusing on the n = 4 composition (DEA₂MA₃Pb₄I₁₃). Structural characterization revealed a substantial improvement in film morphology: DEA-based films exhibited grain sizes of approximately 1.5 μm, compared to less than 150 nm for PEA-based films. This increase in grain size is indicative of reduced grain boundary density, which directly lowers trap-assisted recombination and facilitates more efficient carrier transport.

Researchers from Korea's Jeonbuk National University have developed a rational bilayer surface passivation strategy to address one of the key bottlenecks in vacuum-deposited perovskite solar cells (PSCs): defect-rich, non-uniform crystallization arising from solid-state film formation.

Schematic diagram of device structure. Image from: Advanced Functional Materials

Vacuum thermal evaporation is widely regarded as a scalable route for PSC fabrication, offering precise control over thickness, stoichiometry, and large-area uniformity. However, the absence of a solvent limits mass transport and surface diffusion during film growth, often leading to incomplete crystallization and a high density of surface and grain-boundary defects. In particular, halide vacancies generate uncoordinated Pb²⁺ sites, which act as nonradiative recombination centers, suppress quasi-Fermi level splitting and reduce the achievable open-circuit voltage (V_OC). These defect sites also accelerate ion migration and environmental degradation, undermining device stability. To overcome these limitations, the researchers introduced an “Anchor-and-Seal” bilayer passivation approach based on sequential deposition of ethylenediammonium diiodide (EDAI₂) and 4-methoxy-phenethylammonium iodide (4MeO-PEAI). 

Researchers from UNIST (Ulsan National Institute of Science and Technology), KAUST (King Abdullah University of Science and Technology), the Chinese University of Hong Kong (Shenzhen) and Forschungszentrum Jülich have developed a process-tolerant interfacial engineering strategy that enables high-efficiency perovskite and perovskite/silicon tandem solar cells to be fabricated under ambient conditions, overcoming a known bottleneck in scalable manufacturing.

Self-assembled monolayers (SAMs) are widely used as hole-selective contacts in high-performance perovskite solar cells (PSCs) due to their excellent transparency and low parasitic absorption. However, conventional phosphonic-acid SAMs are highly sensitive to moisture, leading to poor surface coverage, inhomogeneity, and partial exposure of the transparent conductive oxide when processed in air. As a result, high-efficiency devices typically require fabrication in inert atmospheres, limiting throughput and increasing production cost. To address this limitation, the researchers designed a ternary self-assembled molecular contact that incorporates glycerol dimethacrylate (GDMA) and 1-acetylguanidine (AG) into the SAM system. GDMA plays a dual role: it acts as a co-solvent during deposition to improve wetting and film uniformity, and upon mild thermal curing, it forms a hydrophilic binary network that anchors the SAM robustly to the substrate. This network suppresses disruption of the monolayer during subsequent perovskite deposition. Meanwhile, AG is introduced to passivate interfacial defects, further improving charge selectivity and reducing recombination losses.

Trinasolar has announced a new world record for a perovskite/crystalline silicon tandem solar module, achieving a peak power output of 907W and a full-area module efficiency of 29.2%. The module performance has been independently verified by TÜV SÜD.

The record-breaking module is based on Trinasolar’s 210 mm large-area tandem cell technology platform and uses an industry-standard, full-size module area rather than a lab-scale demonstrator. According to the company, the R&D team focused on improving perovskite thin-film uniformity, enhancing interfacial passivation and optimizing spectral absorption matching in the tandem stack, which together enabled higher conversion efficiency and better operational stability.

Sunic System has announced that it will develop deposition equipment for perovskite-based displays, expanding its perovskite equipment business from solar cells into display applications. The company announced that it signed a memorandum of understanding (MOU) with SND Display for the commercialization of next-generation perovskite displays.

The partnership will focus on deposition technologies needed to apply perovskite materials to existing display manufacturing processes. The two companies plan to jointly develop deposition processes and equipment structures optimized for the material characteristics, as well as deposition precursor materials. The collaboration also includes joint technology testing, prototype verification, equipment and process cooperation for mass production, and research aimed at improving deposition uniformity and fine-patterning performance.

The EU-funded LUMINOSITY project is advancing the industrialization of flexible perovskite solar cell (PSC) technology, with a strong focus on scalability, sustainability, and real-world deployment. Coordinated by TNO (Netherlands Organization for Applied Scientific Research), the project brings together leading European research institutes, universities, and industrial partners to bridge the gap between laboratory-scale innovation and large-scale manufacturing.

LUMINOSITY - short for “Large area uniform industry compatible perovskite solar cell technology” - aims to enable commercially viable production of flexible perovskite photovoltaics using established industrial processes. Central to this effort is the adoption of roll-to-roll (R2R) manufacturing, targeting module efficiencies above 20% over areas exceeding 900 cm², while advancing the technology readiness level (TRL) to 7.

Kyocera Communication Systems Co. (KCCS), a Kyocera Group company, has begun installing film-type perovskite solar cells at six public facilities across Japan, marking a step forward in real-world deployment of the technology.

The projects span two regions and local governments. In Shiga Prefecture, film-type perovskite modules will be installed at Hachiman Technical High School, Moriyama Kita High School and the Lake Biwa Museum. In Fukuoka City, systems will be deployed at Takamiya Junior High School, Oiji Elementary School and Haranishi Elementary School.

This is a sponsored post, by Sheldon Wayman, Product Manager, INFICON

Perovskite solar cells have made rapid gains in efficiency, with both single-junction and tandem configurations continuing to set new performance records. As the industry moves toward commercial-scale production, thermal evaporation has emerged as a leading deposition method for many of the layers in the perovskite device stack. This includes the perovskite absorber itself (via co-evaporation of precursors such as PbI₂, CsBr, and MAI), metal contacts, hole and electron transport layers, and buffer layers.

For manufacturers accustomed to chemical vapor deposition and solution-based processes, thermal evaporation introduces a different set of process control requirements. Deposition rates in perovskite manufacturing are often very low, materials can be exotic with poorly characterized physical properties, and multi-source co-evaporation demands simultaneous rate control of each material. The technology that addresses these requirements is quartz crystal microbalance (QCM) monitoring. QCM has decades of proven use in optical coating and OLED manufacturing but is relatively new to the solar industry. Understanding how it works and what it enables is becoming essential as perovskite fabs scale up.

This is especially relevant given one of the central challenges facing perovskite solar today. Long-term cell stability remains an active area of development for the industry. Perovskite devices are sensitive to the thickness and composition of each layer in the device stack. Variations in absorber thickness, transport layer uniformity, or buffer layer coverage can accelerate degradation mechanisms that shorten cell lifetime in the field. Accurate deposition control is not just a manufacturing efficiency concern. It directly affects how long the finished solar cell will perform at its rated output.

Hanwha Qcells has announced that it will supply its perovskite-silicon tandem solar cells for a lunar surface solar power demonstration project, aiming to test the technology’s viability in the harsh conditions of space. Hanwha Q CELLS GmbH, the company’s German unit, will provide perovskite-based tandem cell samples for the Space Science & Technology Evaluation Facility - First Flight Lunar In-Situ Solar Cell Experiment (SSTEF-1), a project funded by NASA and led by US-based Aegis Aerospace Inc.

The Georgia Tech Research Institute (GTRI), a nonprofit applied research unit under the Georgia Institute of Technology, selected Hanwha Qcells’ tandem devices for this mission to evaluate solar cell performance beyond Earth. The samples will be mounted on the surface of a lunar lander and exposed directly to the space environment, including vacuum, extreme temperature swings, ultraviolet radiation and cosmic radiation, in order to gather real-world performance and reliability data.

CHG EnSOL and Suzhou Heimian Optoelectronics Technology Co., Ltd. have announced a strategic partnership to accelerate the development and commercialization of perovskite/silicon tandem photovoltaic technology for space applications. The two companies recently signed a cooperation agreement that includes the establishment of a joint venture dedicated to advancing this next-generation PV architecture.

The collaboration will focus on leveraging each company’s expertise to push tandem cell performance and reliability in demanding space environments, while also promoting the industrialization of related R&D achievements.