Researchers deepen understanding of glass formation and crystallization kinetics in 2D metal halide perovskites

Researchers from Duke University and North Carolina State University have reported glass formation for low-melting-temperature 1-MeHa2PbI4 (1-MeHa = 1-methyl-hexylammonium) using ultrafast calorimetry, thereby extending the range of metal halide perovskite (MHP) glass formation across a broader range of organic (fused ring to branched aliphatic) and halide (bromide to iodide) compositions. 

A few years ago, Akash Singh and collaborators at Duke University set out to explore the realm of glassy perovskites, a departure from the traditionally studied crystalline perovskites. Since then, this topic sparked interest, resulting in the establishment of a novel research domain centered around glass-forming hybrid perovskite semiconductors with reversible switching. This recent discovery of glass formation in MHPs opens new opportunities associated with reversible glass-crystalline switching, with each state offering distinct optoelectronic properties. However, the previously reported [S-(−)-1-(1-naphthyl)ethylammonium]2PbBr4 perovskite is a strong glass former with sluggish glass-crystal transformation time scales, pointing to a need for glassy MHPs with a broader range of compositions and crystallization kinetics.   

Read the full story Posted: Aug 16,2023

Researchers develop flexible perovskite solar cells on PET films that achieve record indoor efficiency

A collaborative effort by researchers from the Centre for Hybrid and Organic Solar Energy (CHOSE), Department of Electronic Engineering at Tor Vergata University of Rome, Italy, the Department of Textile Engineering at the University of Guilan, Iran, GreatCell Solar Italia, Institute of Crystallography (IC-CNR), Italy, Department of Biological and Environmental Sciences and Technologies at the University of Salento, Italy and Institute of Nanotechnology (CNR NANOTEC), Italy, has resulted in the development of flexible perovskite solar cells with remarkable power conversion efficiencies (PCE) under white LED illumination.

The team achieved a maximum PCE of 28.9% at an illuminance of 200 lx and a record of 32.5% at 1000 lx, essentially converting a third of the incoming power (note that under 1 sun this figure for perovskite technology is less, i.e. one quarter).

Read the full story Posted: Aug 16,2023

Microquanta announces its perovskite water-farming PV power station is connected to the grid

Microquanta has reported that its novel perovskite-based PV power station is now connected to the grid. The Company referred to it as a "perovskite commercial rooftop power station", erected over the water for fish farming applications. 

The perovskite power station is located in Qujiang district, Quzhou City, which is rich in water sources and farming. According to local conditions, it adopts the "onboard power generation and offboard farming" model. The installed capacity of the first phase is around 260 kW. The owner is Qujiang Construction Investment. 

Read the full story Posted: Aug 14,2023

Researchers develop efficient organometal halide perovskite photoelectrodes for water splitting

Researchers from Gwangju Institute of Science and Technology (GIST), Korea Research Institute of Chemical Technology (KRICT) and Lawrence Berkeley National Laboratory have developed a highly efficient organometal halide perovskites (OHP)-based photoanode using a rational design approach, which addresses current limitations.

Currently, hydrogen is mainly produced by natural gas, which also generates greenhouse gases such as carbon dioxide as by-products. It is argued that hydrogen produced this way, while economical, is not truly sustainable, and thus requires a more eco-friendly approach for its generation. Photoelectrochemical (PEC) water splitting based on solar energy is one such promising approach. However, its widespread application is limited by a lack of efficient photoanodes for catalyzing the rate-limiting oxygen evolution reaction (OER), an important reaction in PEC water splitting. Organometal halide perovskites (OHPs) have emerged as a promising photoanode material on this front. Unfortunately, OHP-based photoanodes suffer from two undesired losses that limit their efficiency. One is an internal loss resulting from a recombination of photogenerated charge carriers (required for electricity generation) within the anode itself, which, in turn, hinders water splitting. The other is external loss due to the slow reaction kinetics of water splitting, resulting in a loss of charge carriers at the interface of the anode and electrolyte. These are the challenges tackled by the team in this recent work.

Read the full story Posted: Aug 13,2023

Researchers develop ballpoint pens that can write perovskite LEDs on diverse substrates

Researchers from Washington University in St. Louis and  Florida State University have developed a versatile, scalable and eco-friendly handwriting approach to draw multicolor perovskite light-emitting diodes and perovskite photodetectors on various substrates, including paper, textiles, plastics, elastomers, rubber and three-dimensional objects. 

The team's method uses common ballpoint pens filled with newly formulated inks of conductive polymers, metal nanowires and multiple perovskites for a wide range of emission colors. Just like writing with multicolored pens, writing layer-by-layer with these functional inks enables perovskite optoelectronic devices to be realized within minutes.

Read the full story Posted: Aug 12,2023

Researchers develop phase-pure 2D tin halide perovskite thin flakes for stable lasing

Researchers from China's Westlake University, Zhejiang University, Binzhou University and U.S-based Purdue University have reported the synthesis of a series of 2D tin perovskite bulk crystals with high phase purity via a mixed-solvent strategy. 

Ruddlesden-Popper tin halide perovskites are a class of two-dimensional (2D) semiconductors with exceptional optoelectronic properties, high carrier mobility, and low toxicity. However, the team aimed to address the issue of their challenging synthesis and the lack of fundamental understanding of their optoelectronic properties (compared to their lead counterparts). 

Read the full story Posted: Aug 10,2023

Researchers design “cage traps” for lead management of perovskite solar cells

Researchers from Zhengzhou University and the Chinese Academy of Sciences (CAS) have devised a novel lead capturing technique for perovskite solar cells: they implanted a multifunctional mesoporous amino-grafted-carbon net into the perovskite solar cells, creating biomimetic cage traps that could effectively mitigate Pb leakage and shield from external invasion under extreme weather conditions. 

The team then explored the synergistic Pb capturing mechanism in terms of chemical chelation and physical adsorption. Additionally, the Pb contamination assessment of end-of-life perovskite solar cells in the real-world ecosystem, including Yellow River water and soil, was proposed by the scientists. 

Read the full story Posted: Aug 07,2023

Researchers explore the effects of a molecular additive for perovskite LEDs

Researchers from Stanford University and Mississippi State University recently explored the potential of Mn2+-doped perovskite LEDs (PeLEDs) for lighting and display applications. 

By introducing a molecular additive, tris(4-fluorphenyl)phosphine oxide (TFPPO), Mn2+-doped PeLEDs achieved a peak external quantum efficiency of 14.0% and peak luminance (i.e., brightness) of 128,000 cd/m2. These high efficiencies and brightnesses suggest that Mn2+-doped PeLEDs could be implemented in lighting or display applications. However, device stability is also important to consider. The team found that introducing TFPPO compromises the stability of Mn2+-doped PeLEDs—a decrease from 37.0 to 2.54 min. By analyzing both the optoelectronic and photophysical characteristics of Mn2+-doped PeLEDs before and after device operation, the scientists reported insights into this efficiency-stability trade-off.

Read the full story Posted: Aug 05,2023

Researchers improve two key perovskite interfaces for solar cells with better efficiency and lifetime

Researchers at imec and University of Hasselt at Energyville, Belgium, recently set out to improve two key perovskite interfaces for solar cells for efficiency and lifetime.

The work focusses on the upper interface between the perovskite and the fullerene-C60 electron transport layer and the lower interface between the perovskite and the NiOx-based hole transport layer.

Read the full story Posted: Aug 05,2023

Researchers develop a platform for integrated spectrometers based on solution-processable semiconductors

Researchers from China's Harbin Institute of Technology and University of Electronic Science and Technology of China have proposed a facile and universal platform to fabricate integrated spectrometers with solution-processable semiconductors by involving the conjugated mode of the bound states in the continuum (conjugated-BIC) photonics.

Acquiring real-time spectral information in point-of-care diagnosis, internet-of-thing, and other lab-on-chip applications requires spectrometers with hetero-integration capability and miniaturized form. Compared to conventional semiconductors integrated by heteroepitaxy, solution-processable semiconductors provide a much-flexible integration platform due to their solution-processability, and, therefore, more suitable for multi-material integrated systems. However, solution-processable semiconductors are usually incompatible with micro-fabrication processes, making them impractical for use in various applications.

Read the full story Posted: Aug 03,2023