Lead-free

The University of Queensland (UQ) and Halocell Energy have announced they will be working together to advance tin-based perovskite solar panels.

UQ's Australian Institute for Bioengineering and Nanotechnology (AIBN) researcher Dr. Peng Chen has secured almost $200,000 through the latest Australia’s Economic Accelerator Ignite funding round to accelerate the commercial production of tin-based perovskite solar panels. Dr. Chen and his team - including UQ’s Professor Lianzhou Wang and AIBN’s Dr Dongxu He – have replaced the lead with tin, recently setting a world-record efficiency for lead-free perovskite solar cells. Now, Halocell Energy and UQ have decided to take the project to the next phase and scale up for real world use in lead-free solar panels.

Triboelectric nanogenerators (TENGs) based on halide perovskites are considered attractive thanks to their high output performance as micro-nano energy sources. However, the presence of toxic lead and environmental instability hamper their practical applications in wearable electronics. 

To address these challenges, researchers from Shandong University and Henan University have developed a lead-free bismuth halide perovskite, CsBi₃I₁₀ (CBI), integrated with polyvinylidene fluoride (PVDF) in a nanofiber composite film via a one-step electrospinning deposition process, serving as an alternative triboelectric layer for TENGs. 

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.

Researchers from Chung-Ang University (CAU), Kyoto University, Chungnam National University, Chungbuk National University and Gyeongsang National University have developed a halogen composition–independent strategy for realizing wide-bandgap (WBG) tin-based perovskite solar cells (TPSCs), by partially substituting formamidinium with dimethylammonium (DMA) in the A-site of the perovskite lattice. This substitution is said to expand the lattice, widening the bandgap from 1.63 to 1.72 eV without requiring additional bromine. 

Schematic of the ST-TPSC device structure. Image credit: Small

Comprehensive structural and optical analyses revealed enhanced crystallinity, reduced strain, and improved film morphology. Furthermore, ultraviolet photoelectron spectroscopy confirmed enhanced band alignment with the hole transport layer, enabling more efficient charge extraction. 

Researchers from Mexico's Autonomous University of Querétaro recently addressed PSCs' stability and toxicity concerns by exploring chalcogenide perovskites, specifically ABSe₃ (where A = Ca, Ba, and B = Zr, Hf), as alternatives. These materials exhibit excellent optoelectronic properties, superior thermal and structural stability, and a non-toxic composition, making them ideal candidates for efficient, lead-free solar cells. 

The research team investigated the integration of CaZrSe₃, BaZrSe₃, CaHfSe₃ and BaHfSe₃ as absorber layers in solar cells. The scientists optimized their performance using the Solar Cell Capacitance Simulator in One Dimension (SCAPS-1D), a computational tool developed at the University of Ghent. This simulation allowed them to analyze the behavior of these materials under real-world conditions.

Over the past five years, six Fraunhofer Institutes combined their expertise in the Fraunhofer lighthouse project "MaNiTU" to identify the most sustainable paths to market of perovskite-silicon tandem solar cells made of stable materials and manufactured using scalable production processes. They were able to show that high cell efficiencies can be achieved using industry-oriented processes, however, they found that such high efficiencies were only currently achievable with lead perovskite materials. Based on these findings, the researchers developed suitable recycling concepts to ensure sustainability.

In the "MaNiTU" project, the Fraunhofer researchers produced new materials with perovskite crystal structures and compared them with existing materials at the cell level. The comparisons showed that high efficiencies can only be achieved with lead perovskites. They then successfully fabricated highly efficient demonstrators, for example, a perovskite silicon tandem solar cell of more than 100 square centimeters with screen-printed metallization and produced mini modules for single and interconnected tandem solar cells. Subsequent life cycle analyses showed that by using suitable production and recycling processes and degradation rates comparable to today's silicon technology, it is feasible to make a sustainable product.

Researchers from India's Madan Mohan Malaviya University of Technology, University of Delhi, Manipal University and Sweden's IAAM have combined 2D and 3D perovskites to strengthen both reliability and efficiency of 3D perovskite solar cells (PSCs). 

The team explored the combined effect of Dion-Jacobson (DJ) 2D-3D halide-based perovskites layers on device performance. The DJ 2D material used was PeDAMA₄Pb₅I₁₆, while the 3D material is the lead-free, stable CsGeI_3-xBr_x (with x=1). The optimized solar cell structure developed in this work consisted of (Au/Cu₂O/PeDAMA₄Pb₅I₁₆/CsGeI_3-xBr_x/PCBM/FTO). 

Researchers from China's Jiangxi Normal University, Chinese Academy of Sciences (CAS) and City University of Hong Kong have developed a self-driven X-ray detection device using high resistivity zero-dimensional lead-free perovskite ferroelectric single-crystal (NMP)₃Sb₂Br₉. The device exhibits an excellent self-driven X-ray detection performance, with an ultra-low detection limit of 84.1 nGyair/s, approximately 60 times lower than that of commercial α-Se (5500 nGyair/s).

The self-driven detection mode without external bias has been proven to be an effective means of reducing the limit of detection (LoD) due to its low current noise characteristics. Additionally, the zero-dimensional distinctive isolated framework results in a high resistivity of 1.39 × 1011 W cm, which effectively reduces the current noise and suppresses ion migration. 

A Research Group led by Prof. Eva Unger at Helmholtz Zentrum Berlin (HZB), in collaboration with the Indian Institute of Technology Bombay and University of Jammu, has reported the use of inkjet printing to fabricate thin films of combinatorial mixed formamidinium tin-lead perovskites and evaluated their layer quality and device performance. The team focused on optimizing the inkjet-printing process to ensure precise film deposition and enhance device performance.

Image credit: ACS Applied Materials and Interfaces

The scientists deposited Sn/Pb intermixed FASn_1–xPb_xI₃ (x = 0.25, 0.5, and 0.75)-based perovskite thin films through inkjet printing. The study focused on finding the ideal composition ratio for a favorable photovoltaic performance. The deposited FASn_1–xPb_xI₃ thin films were subjected to various characterizations followed by their implementation in solar cells. 

Zinc-ion batteries (ZIBs) are emerging as a candidate for use as an efficient and sustainable energy storage solution, offering advantages in terms of cost-effectiveness, safety, and performance. The key to commercializing ZIBs lies in developing cathode materials that offer high specific capacity and prolonged cycle performance. 

In a recent study, researchers from the Indian Institute of Science and University of Melbourne have demonstrated the capability of environmentally friendly, lead-free inorganic perovskites for high-rate rechargeable aqueous zinc-ion batteries with enhanced stability and excellent rate performance.