Carrier Generation and Recombination

UC Irvine-led research reveals that the optical properties of materials can be dramatically enhanced—not by changing the materials themselves, but by giving the light new properties.

Perfluoroalkyl substances (PFAS), nicknamed "forever chemicals," pose a growing environmental and health threat. Since the invention of Teflon in 1938, PFAS and perfluorinated polymers or PFs have been widely used for their exceptional stability and resistance to water and heat.

In art, the negative space in a painting can be just as important as the painting itself. Something similar is true in insulating materials, where the empty spaces left behind by missing electrons play a crucial role in determining the material's properties. When a negatively charged electron is excited by light, it leaves behind a positive hole. Because the hole and the electron are oppositely charged, they are…

A new approach to developing semiconductor materials at tiny scales could help boost applications that rely on converting light to energy. A Los Alamos-led research team incorporated magnetic dopants into specially engineered colloidal quantum dots—nanoscale-size semiconductor crystals—and was able to achieve effects that may power solar cell technology, photo detectors and applications that depend on light to…

Excitons are electron-hole pairs in semiconductors that are electrostatically bound by strong Coulombic interactions. In ultrathin 2D semiconductors that are a few atoms thick (typically ~0.7 nm), the decreased z-dimension presents strong quantum confinement and reduced dielectric effects that feature a plethora of stable excitonic species (neutral excitons, trions, biexcitons, defect-bound excitons).

In a result decades in the making, Los Alamos scientists have achieved light amplification with electrically driven devices based on solution-cast semiconductor nanocrystals—tiny specs of semiconductor matter made via chemical synthesis and often called colloidal quantum dots.

In a new study, scientists have observed long-lived excitons in a topological material, opening intriguing new research directions for optoelectronics and quantum computing.

Detection in multiple infrared (IR) regions spanning from short- and mid- to long-wave IR plays an important role in diverse fields from scientific research to wide-ranging technological applications, including target identification, imaging, remote monitoring, and gas sensing. Currently, state-of-the-art IR photodetectors are mainly dominated by conventional narrow bandgap semiconductors including In1-xGaxAs,…

Photocatalysis is a green and sustainable technology that has received extensive attention because of its ability to utilize solar energy to address the energy crisis and environmental pollution. Water pollution is mainly caused by contaminants consisting of heavy metal ions and organic pollutants. Among these, organic pollutants possess high toxicity, carcinogenicity, and refractory degradation, posing a serious…

Photoelectrochemical (PEC) water splitting is a promising green technique for renewable hydrogen production. To construct a practical PEC system, it is of great significance to develop efficient photoanodes. BiVO4 has been identified as the most promising photoanode material because of its narrow band gap and favorable band positions for hydrogen and oxygen evolution. Nevertheless, BiVO4 has limitations of low…

Researchers have demonstrated that a solid can exhibit an enhanced nonlinear optical phenomenon usually seen only in cold atomic gases.

Although halide perovskite light-emitting devices exhibit exceptional properties, such as high efficiency, high color purity and broad color gamut, their industrial integration generally suffers from the technological complexity of devices' multilayer structure alongside in-operation-induced heating poor stability.

Solar energy is the cheapest and most accessible form of energy. Now, it promises to be more efficient than ever. Scientists from a Chinese solar technology company have developed a new type of solar cell that could be a game-changer in the world's transition towards renewable energy.

From Electric Vehicles to Renewable Energy: Aehr Test Systems Tools Are Critical To Tomorrow's Future

Silicon, the standard semiconducting material used in a host of applications—computer central processing units (CPUs), semiconductor chips, detectors, and solar cells—is an abundant, naturally occurring material. However, it is expensive to mine and to purify.

The tandem solar cell converts 32.5% of the incident solar radiation into electrical energy. This value is now officially certified and included in the NREL chart.

Two-dimensional covalent organic frameworks (2D COFs) are a new class of organic semiconductors, and have recently demonstrated great potential for solar fuel production. They are generally formed from the ordered π-π stacking of molecular layers, and usually possess periodic columnar π-arrays that can facilitate the interlayer charge transfer.

National University of Singapore scientists have demonstrated the non-invasive imaging of both the organic layers and underlying inorganic lattice of two-dimensional (2D) hybrid perovskites at the sub-angstrom level.

So-called PERC cells are used in mass production of silicon solar cells, they are considered the workhorses of photovoltaics, dominating the market. Now two teams have shown that such standard silicon cells are also suitable as a basis for tandem cells with perovskite top cells. Currently, the efficiency of the tandem cell is still below that of optimised PERC cells alone, but could be increased to up to 29.5%…

The contributions of photon recycling and light scattering to the performance of perovskite solar cells are quantified.