A research team led by Profs. Wang Mingtai and Chen Chong from the Hefei Institutes of Physical Science of the Chinese Academy of Sciences has developed an antimony trisulfide (Sb₂S₃) solar cell with a record conversion efficiency of 8.21%. This achievement marks the highest performance ever reported for this type of solar cell.

The study was published in Advanced Energy Materials.

Sb₂S₃ has drawn increasing attention as a promising light-absorbing material due to its abundance, non-toxicity, and favorable optoelectronic properties. However, devices fabricated via solution methods typically suffer from high defect densities and interface mismatches, which limit carrier transport and restrict photovoltaic conversion efficiencies to around 6–7%.

To overcome these challenges, the researchers proposed a full-dimensional defect passivation approach using the permeation effect of degradable phenethylammonium iodide (PEAI) in amorphous Sb₂S₃ films.

PEAI pretreatment of amorphous Sb₂S₃ films enables [hk1]-oriented crystallization, full-dimensional defect passivation (bulk and interfaces), and dual-interface energy-level reconstruction via Cd-I and Sb-I bonding. The PEAI reduces CdS surface energy and preferentially adsorbs on Sb₂S₃ (211) planes, promoting [hk1] orientation and enhancing carrier transport.

Furthermore, the penetrated PEAI increases the carrier lifetime by a factor of 3.7, verifying effective defect suppression.

As a result, the researchers successfully fabricated an Sb₂S₃ bulk heterojunction solar cell with a conversion efficiency of 8.21%, the highest reported to date.

This work sets a new performance benchmark for Sb₂S₃ solar cells and provides valuable insights for the design of next-generation, high-efficiency thin-film solar cells.

When Microsoft announced it was ending support for Windows 10 last week, about 40% of all Windows users faced limited options.

While some of those users can upgrade to Windows 11, hundreds of millions of devices don’t meet the technical requirements.

Those users might be wondering what else they can do besides throwing away their current device and buying a new one or risking running outdated software on it.

The tech conglomerate faced backlash from environmental and cybersecurity experts after informing Windows users that it would cease providing updates for Windows 10.

These experts have warned that rendering hundreds of millions of devices practically useless will worsen the ever-growing problem with electronic waste (e-waste) and leave users who can’t upgrade vulnerable to cybersecurity threats.

Researchers from Georgia Tech’s School of Interactive Computing (SIC) and School of Cybersecurity and Privacy (SCP) echo those concerns.

Forcing users to replace their devices means that up to 240 million old devices, according to one analysis, will inevitably end up in landfills.

“The problem of e-waste raises the question of why and how these technologies become obsolete,” said Cindy Lin, a Stephen Fleming Early Career Assistant Professor in SIC.

Lin studies data structures and environmental governance in Southeast Asia and the U.S.

“Scholarship in human-computer interaction (HCI) on repair reveals that many of these technologies suffer from planned obsolescence,” she said. “This means that companies have designed products with a short lifespan, increasing consumption and waste simultaneously.”

When e-waste is dumped in landfills, the organic materials within devices decompose, producing methane, a potent greenhouse gas. And with every discarded device comes the need to produce new ones. The raw materials of these devices are mined, refined, and processed, consuming enormous amounts of energy through the burning of fossil fuels.

The problem with hackers

Though Microsoft said it will continue to provide Windows 10 security updates for one year, users are still being pressured to upgrade. By this time next year, if users still haven’t upgraded to Windows 11, they can expect to become easy targets for cyber criminals.

For example, users could receive phishing emails claiming to be from Microsoft about security updates from hackers pretending to be Microsoft.

“The cybersecurity implications are very serious because new vulnerabilities of Windows 10 will go unpatched for a large part of the user base of this system,” said Mustaque Ahamad, Regents’ Entrepreneur Professor and interim chair of SCP.

“These users will become targets of hackers and cyber criminals who will be able to exploit these vulnerabilities. This will make these machines more prone to attacks such as ransomware and data exfiltration.”

What can users do?

Buying a new device typically costs about $300 at the low end, while some gaming computers can exceed $2,500.

Josiah Hester, an associate professor in the School of IC who researches computing and sustainability, said users who want to avoid discarding their devices can install Linux Mint, a free universal operating system.

“I would hope that instead of discarding, people might see this as an opportunity to go into a more open ecosystem like Linux Mint, which was designed for Windows users,” Hester said.

“So much perfectly good hardware is obsolesced by force, when users are more than willing to give it a second life, either through ending support on the software side, subscription services that require certain versions of an OS, or even building the hardware or low-level functions that reduce the autonomy of device owners.”

Linux Mint is open source and offers its own suite of software products, including a word processor. It also has a built-in security system. It requires 2GB of RAM, 20GB of disk space, and 1024×768 resolution to operate.

On a systemic level, Lin and Hester said people can support organizations that advocate for right to repair and legislation that protects consumers from planned obsolescence.

“HCI studies of informal economies of improvisation and repair have demonstrated that technologies have a longer lifecycle if we have access to expertise on how to repair them without facing penalties such as copyright violations,” Lin said.

“The ongoing right-to-repair movement in the U.S. shows promise in making technology repairable and, in turn, more sustainable.”

Lauren Goode: Well, they’re all interested in growing more. Who among us, Mike? But the hyperscalers refers to this class of major tech companies or cloud service providers. So Meta, Amazon, Microsoft, Google, they’re all in that category.

Molly Taft: Yeah, and I think it’s important to remember that these companies have so much money and they have an ability to raise capital like nobody’s business. So they’re able to do some really crazy stuff to build quick and to build-out really, really big. And they’re getting pretty creative, because their goals right now are to build these things quickly and get them up and running so they can basically use this physical infrastructure to compete with each other.

Lauren Goode: I think that’s right, Molly. I think there’s a lot of frenemy building happening right now, and I would just love to be a part of their group chats when all of these announcements are being made.

Michael Calore: Yeah, and speaking of frenemies, the other sphere of influence that these companies are operating in is the political sphere. Obviously, in order to build a giant data center somewhere, you need to have the political will to do it, which means you need buy-in from the local residents, the local government, the state, the country. So what’s happening in the political sphere with folks who want to build more data centers and people who oppose it, regulation? How is that playing out?

Molly Taft: That’s a great question, and I think if you look at the national conversation, it’s quite different than what’s happening on the local level. You have Washington, you obviously have an administration that is very friendly to the idea of an American AI empire. Importantly for the energy conversation, the way that the Trump administration has approached this support has been through support of fossil fuels. They would really like for all data centers to be powered with oil and gas, a little bit of nuclear and coal. And this works out great for those industries as well. If you’re going to have this massive expansion of power demand, it’s really cool to be in the middle of that and be the one that everyone wants to turn to for energy resourcing. And then on the other side, there has been this influx of local opposition to these data centers for a variety of reasons, be it the water use, be it fears about rising electricity rates, be it noise, and some of the really big struggles have catapulted this issue to national conversation. I’m thinking about xAI in Memphis. When Elon Musk wanted to get xAI up and running, he installed a bunch of unpermitted gas turbines in order to get xAI working that he installed in a majority Black community in Memphis that already had severe issues with air pollution and asthma. And those folks made themselves known. Earlier this year, there was an attempt in DC to impose a moratorium on any state regulation around AI at all. It was an incredibly broad inclusion in the Big Beautiful Bill that ultimately didn’t succeed. But one of the people who opposed it publicly was Marjorie Taylor Greene, who actually mentioned data centers in her opposition, and she compared AI to Skynet, the fictional AI from the Terminator movie franchise. So, this is getting some strange bedfellows in league with each other, I think this kind of contrast between what the administration is trying to push forward and some very powerful energy companies that stand to gain from it, versus some truly grassroots local movements and people concerned about the impacts of what these things are going to do in their communities.