In the quest for energy independence, researchers have studied solar thermoelectric generators (STEGs) as a promising source of solar electricity generation. Unlike the photovoltaics currently used in most solar panels, STEGs can harness all kinds of thermal energy in addition to sunlight. The simple devices have hot and cold sides with semiconductor materials in between, and the difference in temperature between the sides generates electricity through a physical phenomenon known as the Seebeck effect.

But current STEGs have major efficiency limitations preventing them from being more widely adopted as a practical form of energy production. Right now, most solar thermoelectric generators convert less than 1% of sunlight into electricity, compared to roughly 20% for residential solar panel systems.

That gap in efficiency has been dramatically reduced through new techniques developed by researchers at the University of Rochester’s Institute of Optics.

An international team led by UCL researchers has developed durable new solar cells capable of efficiently harvesting energy from indoor light, meaning that devices such as keyboards, remote controls, alarms and sensors could soon be battery-free.

The team used a material called perovskite, which is increasingly used in outdoor solar panels, and unlike traditional silicon-based solar panels, has the potential to be used indoors as well as its composition can be adjusted to better absorb the specific wavelengths of indoor light.

A major drawback of perovskite, however, is that it contains tiny defects in its crystal structure —known as traps—that can cause electrons to get stuck before their energy can be harnessed. These defects not only interrupt the flow of electricity but also contribute to the material’s degradation over time.

Perovskite is a rising star in the field of materials science. The mineral is a cheaper, more efficient alternative to existing photovoltaic materials like silicon, a semiconductor used in solar cells. Now, new research has shown that applying pressure to the material can alter and fine-tune its structures—and thus properties—for a variety of applications.

Using the Canadian Light Source (CLS) at the University of Saskatchewan, a team of researchers observed in real time what happened when they “squeezed” a special type of perovskite between two diamonds. 2D hybrid perovskite is made up of alternating organic and inorganic layers. It’s the interaction between these layers, says Dr. Yang Song, professor of chemistry at Western University, that determines how the material absorbs, emits, or controls light.

The research team found that applying pressure significantly increased the material’s photoluminescence, making it brighter, which Song says hints at potential applications in LED lighting. The team also observed a continuous change in its color from green to yellow to red. “So you can tune the color.” Being able to observe changes to the material as they happen using ultrabright synchrotron light was critical to their research, said Song.

This breakthrough technology from KIMS can lower manufacturing costs and overcome critical moisture issues.

Transparent aluminum oxide (TAlOx), a real material despite its sci-fi name, is incredibly hard and resistant to scratches, making it perfect for protective coatings on electronics, optical sensors, and solar panels. On the sci-fi show Star Trek, it is even used for starship windows and spacefaring aquariums.

Current methods of making TAlOx are expensive and complicated, requiring high-powered lasers, vacuum chambers, or large vats of dangerous acids. That may change thanks to research co-authored by Filipino scientists from Ateneo de Manila University.

Instead of immersing entire sheets of metal into acidic solutions, the researchers applied microdroplets of acidic solution onto small aluminum surfaces and applied an electric current. Just two volts of electricity—barely more than what’s found in a single AA household flashlight battery—was all that was needed to transform the metal into glass-like TAlOx.