Researchers achieve 3D printing of luminescent perovskite quantum dot–polymer architectures

Researchers from Ulsan National Institute of Science and Technology (UNIST), Korea Electrotechnology Research Institute (KERI) and Sungkyunkwan University (SKKU) recently developed a straightforward and effective method for producing 3D architectures of perovskite quantum dot (PQD)-encapsulated high-performance composites (PQD-HPCs) through direct-ink writing (DIW). 

Schematic of the direct-ink writing (DIW) approach of luminescent PQD–polymer architectures. Image from Advanced Functional Materials

Led by Professor Im Doo Jung from the Department of Mechanical Engineering at UNIST, the recent study introduced a cutting-edge one-stop perovskite quantum dot (PQD) additive manufacturing technology. This approach eliminates the need for heat treatment, allowing for the creation of complex 3D shapes with exceptional precision, including iconic landmarks like the Eiffel Tower.

Read the full story Posted: May 04,2024

Researchers use thiocyanate ions to boost the efficiency of perovskite/organic solar cells

Researchers from Soochow University, Hunan University and Friedrich-Alexander University Erlangen-Nürnberg have incorporated pseudo-halogen thiocyanate (SCN) ions in iodide/bromide mixed halide perovskites and showed that they enhance crystallization and reduce grain boundaries. 

While perovskite/organic tandem solar cells could theoretically achieve high efficiency and stability, their performance is hindered by a process known as phase segregation, which degrades the performance of wide-bandgap perovskite cells and adversely affects recombination processes at the tandem solar cells' interconnecting layer. The team devised a strategy to suppress phase segregation in wide-bandgap perovskites, thus boosting the performance and stability of perovskite/organic tandem cells. This strategy entails the use of a pseudo-triple-halide alloy incorporated in mixed halide perovskites based on iodine and bromine.

Read the full story Posted: May 02,2024

Researchers use novel additive to develop efficient tin halide perovskite solar cell

An international group of researchers, led by the Chungbuk National University in South Korea, has reported a tin halide perovskite (Sn-HP) solar cell that uses an additive known as 4-Phenylthiosemicarbazide (4PTSC) to reduce imperfections in the perovskite layer.

Using wide bandgap tin halide perovskites (Sn-HP) could pose an eco-friendly option for multi-junction Sn-HP photovoltaics, but rapid crystallization often results in poor film morphology and substantial defect states, hampering device efficiency. The team's work aims to introduce a novel multifunctional additive to tackle these issues.

Read the full story Posted: May 01,2024

Researchers develop thin, flexible quasi-2D PSCs and demonstrate them in energy-autonomous drones

Researchers from Austria's Johannes Kepler University Linz have developed lightweight, thin (<2.5 μm), flexible and transparent-conductive-oxide-free quasi 2D perovskite solar cells by incorporating alpha-methylbenzyl ammonium iodide into the photoactive perovskite layer. 

The team fabricated the devices directly on an ultrathin polymer foil coated with an alumina barrier layer to ensure environmental and mechanical stability without compromising weight and flexibility.

Read the full story Posted: Apr 28,2024

Researchers create all-inorganic perovskite nanocrystalline glass doped with rare-earth ions

Researchers from China's Kunming University of Science and Technology and Southwest United Graduate School have doped rare-earth ions into borosilicate glass for the first time to induce the self-crystallization of CsPbBr3 QDs.

All-inorganic perovskite quantum dots (QDs) in glass materials, specifically CsPbX3 (X = Cl, Br, I), have potential as next-generation fluorescent materials due to their impressive luminous performance and stability. However, the crystallization process of quantum dots within the glass presents a challenge, leading to uneven crystallinity and subsequent reductions in light efficiency, thereby affecting practical applications. In glass ceramics doped with rare-earth oxides, the introduction of rare-earth ions as nucleating agents can promote the self-precipitation of nanocrystalline crystals within the glass. 

Read the full story Posted: Apr 27,2024

Researchers develop integrated deposition and passivation strategy for controlled crystallization of 2D/3D halide perovskite films

Researchers from the University of Stuttgart, Lawrence Berkeley National Laboratory and Brandenburg University of Technology Cottbus-Senftenberg have introduced a simplified deposition procedure for multidimensional (2D/3D) perovskite thin films, integrating a phenethylammonium chloride (PEACl)-treatment into the antisolvent step when forming the 3D perovskite. 

The “traditional” deposition and passivation processes (top row) and the integrated deposition and passivation strategy to form 2D passivated 3D halide perovskite films (bottom row). Image from Advanced Materials.

This recently developed simultaneous deposition and passivation strategy reduces the number of synthesis steps while simultaneously stabilizing the halide perovskite film and improving the photovoltaic performance of resulting solar cell devices to 20.8%. 

Read the full story Posted: Apr 26,2024

Researchers develop flexible quasi-2D perovskite solar cells with high specific power and improved stability for energy-autonomous drones

Researchers at Austria's Johannes Kepler University Linz have developed lightweight, thin (<2.5 μm), flexible and transparent-conductive-oxide-free quasi-two-dimensional perovskite solar cells by incorporating alpha-methylbenzyl ammonium iodide into the photoactive perovskite layer. 

The team fabricated the devices directly on an ultrathin polymer foil coated with an alumina barrier layer to ensure environmental and mechanical stability without compromising weight and flexibility. 

Read the full story Posted: Apr 21,2024

Researchers highlight the potential of ambient air annealing for efficient inorganic CsPbI3 perovskite solar cells

Researchers from Helmholtz-Zentrum Berlin (HZB) and the University of Potsdam have analyzed surfaces and interfaces of CsPbI3 films, produced under different conditions, at BESSY II. They found that annealing in ambient air does not have an adverse effect on the optoelectronic properties of the semiconductor film, but actually results in fewer defects. This could simplify the mass production of inorganic perovskite solar cells.

The best performing perovskite semiconductors contain organic cations such as methylammonium, which cannot tolerate high temperatures and humidity, so their long-term stability is still a challenge. However, methylammonium can be replaced by inorganic cations such as Cesium (Cs). Inorganic halide perovskites with the molecular formula CsPbX3 (where X stands for a halide such as chloride, bromide and iodide) remain stable even at temperatures above 300 °C. CsPbI3 has the best optical properties for photovoltaics (band gap ∼1.7 eV).

Read the full story Posted: Apr 20,2024

Researchers develop novel vapor deposition technique based on continuous flash sublimation for rapid fabrication of all-inorganic perovskite solar cells

Researchers at NREL, BlueDot Photonics, University of Washington, Colorado School of Mines and Rochester Institute of Technology have developed a vapor deposition technique based on continuous flash sublimation (CFS) to fabricate all-inorganic perovskite thin films in under 5 minutes in a continuous process. The adoption of the proposed approach may also result in higher power conversion efficiencies of perovskite solar cell.

Schematic illustration of the continuous flash sublimation (CFS) approach consisting of a mechano-chemical synthesis of the source powder (here CsPb(IxBr1−x)3), the high-throughput deposition process in a home-made evaporation system, and a short post-annealing treatment to improve thin-film quality. Image from Journal of Materials Chemistry A

The team described the new technique as a non-batch process that solves two problems associated with the use of established vapor processing in perovskite material manufacturing – the slow speed of deposition and the non-continuous nature of batch processing.

Read the full story Posted: Apr 18,2024

Researchers develop strategy that yields 24.67%-efficiency doctor-bladed perovskite solar cells

Scalable deposition of high-efficiency perovskite solar cells (PSCs) is vital to achieving commercialization. However, a significant number of defects are distributed at the buried interface of perovskite film fabricated by scalable deposition, which adversely affects the efficiency and stability of PSCs. Now, researchers at China's Central South University, Hunan Institute of Engineering and  Chinese Academy of Sciences (CAS) addressed this issue by incorporating 2-(N-morpholino)ethanesulfonic acid potassium salt (MESK) as the bridging layer between the tin oxide (SnO2) electron transport layer (ETL) and the perovskite film deposited via scalable two-step doctor blading. 

The scientists reported that both experiment and simulation results demonstrated that MESK can passivate the trap states of Sn suspension bonds, thereby enhancing the charge extraction and transport of the SnO2 ETL. 

Read the full story Posted: Apr 16,2024