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Perovskite solar cells are among the most promising candidates for the next generation of photovoltaics: lightweight, flexible, and potentially very low-cost. However, their tendency to degrade under sunlight and heat has so far limited widespread adoption. Now, a new study published in Joule presents an innovative and scalable strategy to overcome this key limitation.

A research team led by the École Polytechnique Fédérale de Lausanne (EPFL), in collaboration with the University of Applied Sciences and Arts of Western Switzerland (HES⁠-⁠SO) and the Politecnico di Milano, has developed a bulk passivation technique that involves adding the molecule TEMPO (2,2,6,6-tetramethylpiperidine-1-oxyl) to the perovskite film and applying a brief infrared heating pulse lasting just half a second.

This approach enables the repair of near-invisible crystalline defects inside the material, boosting solar cell efficiency beyond 20% and maintaining that performance for several months under operating conditions. Using positron annihilation spectroscopy—a method involving antimatter particles that probe atomic-scale defects—the researchers confirmed a significant reduction in vacancy-type defects.

When you put your hand out the window of a moving car, you feel a force pushing against you called drag. This force opposes a moving vehicle, and it’s part of the reason why your car naturally slows to a stop if you take your foot off the gas pedal. But drag doesn’t just slow down cars.

Aerospace engineers are working on using the drag force in space to develop more fuel-efficient spacecraft and missions, deorbit spacecraft without creating as much space junk, and even place probes in orbit around other planets.

Space is not a complete vacuum − at least not all of it. Earth’s atmosphere gets thinner with altitude, but it has enough air to impart a force of drag on orbiting spacecraft, even up to about 620 miles (1,000 kilometers).

Not everyone needs 8 hours of sleep to function properly. Some people can feel well-rested and show no negative effects of sleep deprivation, even after just 4 hours of sleep, which is likely the result of a genetic mutation.

A recent study has reported that a mutation in salt-induced kinase 3 (hSIK3-N783Y)—a gene critical for regulating sleep duration and depth—may be the reason why some people are natural short sleepers (NSS).

The findings of this study are published in Proceedings of the National Academy of Sciences.

As far back as we can observe in our Universe, time always behaved in exactly the same fashion we’re familiar with: ticking away, relentlessly, at the same rate for all observers. Bring your clock to the surface of the Earth? The bottom of the ocean? Into orbit in space? Near the event horizon of a black hole? Or speeding through intergalactic space at close to the speed of light? It doesn’t matter. The amount of time it takes for regular events to occur — for a second to tick by, for an atomic transition to occur, for a photon of a specific wavelength to have one “wave” pass by you, etc. — is going to be identical for any observer under any of those conditions. In fact, the rate at which time passes for themselves, at one second-per-second, is something all observers can agree on.

Sure, relativity is weird in a lot of ways, both when you move close to the speed of light or when the curvature of spacetime is very strong. Lengths contract, time durations dilate, and different observers draw different conclusions for one another versus for themselves. But time still passes, and relativity allows us to reconcile those differences. But what about if we go to an unfamiliar place; what if we consider what happens before the Big Bang? That’s what Justin Skit wants to know, asking:

“Can you help me understand what’s going on with time during cosmic inflation? I know inflation starts and then the big bang. But if the era before the big bang was timeless how does that work?”

Valve founder Gabe Newell’s neural chip company Starfish Neuroscience announced it’s developing a custom chip designed for next-generation, minimally invasive brain-computer interfaces—and it may be coming sooner than you think.

The company announced in a blog update that it’s creating a custom, ultra-low power neural chip in collaboration with R&D leader imec.

Starfish says the chip is intended for future wireless, battery-free brain implants capable of reading and stimulating neural activity in multiple areas simultaneously—a key requirement for treating complex neurological disorders involving circuit-level dysfunction. That’s the ‘read and write’ functions we’ve heard Newell speak about in previous talks on the subject.

Gabe Newell, co-founder of Valve, sat down with IGN for a chat about the company, the promise of VR, and Newell’s most bleeding edge project as of late, brain-computer interfaces (BCI).