Category Physics

‘Solar battery’ stores sunlight for days, then releases hydrogen on demand

'Solar battery' stores sunlight for days, then releases hydrogen on demand
Catalyst solutions with luminescent ruthenium dye, which are irradiated with visible light in the reactor. Credit: Elvira Eberhardt, Ulm University

A new material can store energy from sunlight and convert it into hydrogen days later. The material, jointly developed by researchers from Ulm and Jena, can do this even in the dark. The process is reversible and can be reactivated several times using a pH switch. The results are published in the journal Nature Communications.

Green hydrogen is one of the most important pillars of the energy transition. It is produced from sunlight using photocatalytic processes. There are now a variety of technologies for converting and storing solar energy into chemical energy...

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Quantum effect could power the next generation of battery-free devices

A new study has revealed how tiny imperfections and vibrations inside a promising quantum material could be used to control an unusual quantum effect, opening new possibilities for smaller, faster, and more efficient energy-harvesting devices.

The international team, led by Professor Dongchen Qi from the QUT School of Chemistry and Physics and Professor Xiao Renshaw Wang from Nanyang Technological University in Singapore, studied the mechanism governing the so-called nonlinear Hall effect (NLHE). The research is published in the journal Newton.

Unlike the classical Hall effect, this quantum version allows alternating electrical signals, like those found in wireless or ambient energy sources, to be converted directly into usable direct current without the need for traditional dio...

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Your car’s tire sensors could be used to track you

Your car's tire sensors could be used to track you
This paper demonstrates how a network of low-cost spectrum receivers can capture and analyze the movement patterns of vehicles, inferring car owners’ routines. Credit: IMDEA Networks Institute

Researchers at IMDEA Networks Institute, together with European partners, have found that tire pressure sensors in modern cars can unintentionally expose drivers to tracking. Over a ten-week study, they collected signals from more than 20,000 vehicles, revealing a hidden privacy risk and highlighting the need for stronger security measures in future vehicle sensor systems.

How tire sensors quietly share data
Most modern cars are equipped with a Tire Pressure Monitoring System (TPMS), mandatory since the late 2000s in many countries for their contribution to road safety...

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Hair-width LEDs could eventually replace lasers

Roark Chao in lab
Doctoral student Roark Chao researches microLEDs at UC Santa Barbara, Photo Credit Matt Perko

LEDs no wider than a human hair could soon take on work traditionally handled by lasers, from moving data inside server racks to powering next-generation displays. New research co-authored by UC Santa Barbara doctoral student Roark Chao points to a practical path forward. The study is published in the journal Optics Express.

“We’re talking about devices that are literally the size of a hair follicle,” said Chao, who studies electrical engineering. “If you can engineer how the light comes out, those microLEDs can start to replace lasers in short-distance data communication.”

The work builds on UCSB’s longstanding strengths in gallium nitride research and optoelectronics...

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