Nanoscience and Advanced Materials

The case of the vanishing seeds: How curiosity-driven research is future-proofing “Smart Windows”

Daniel Morton — Tue, 27 Jan 2026 17:02:14 +0000

The case of the vanishing seeds: How curiosity-driven research is future-proofing “Smart Windows” Daniel Morton Tue, 01/27/2026 - 10:02

Daniel Morton

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Have you ever walked into a room on a glorious Colorado summer day and felt the heat radiating through the glass?

We usually solve this by cranking up the air conditioning or closing the blinds, losing our mountain view in the process. But what if the window itself could think? A team led by Mike McGehee, a Fellow at RASEI, describes research that improves the robustness of such a device.

For years researchers have been working on “smart windows”, devices that could “sense” the conditions outside and “react” to them. This investigation centers around a promising technology called Reversible Metal Electrodeposition (RME). The technical details of this process are complex, but you can understand the concept by thinking of it as a reversible coat of paint. At the flip of a switch, a thin layer of metal, in this case silver, spreads across the glass to form a layer that tints it, blocking out the heat and the glare. Flip the switch again and the silver dissolves back into a clear liquid, making the window transparent.

Buildings are responsible for consuming around 40% of all generated energy globally, much of which is expended in regulating the temperature, heating and cooling the building interior. Installing smart windows that can react to the environmental conditions could provide a very effective mechanism to reduce energy use and slash energy bills by automatically managing how much heat enters a room. It has been estimated that just by controlling the amount of sunlight that is let into a building through a window, we could cut energy bills by up to as much as 20%.

However, there have been a number of challenges to overcome in order to take this initial discovery from the lab to a product that can be deployed for use in buildings. One challenge is that early versions of these windows started out fast but grew “lazy” over time. After a few thousand uses the tinting / de-tinting process slowed, taking almost four times longer than it did on day one.

This is where the researchers undertook some detailed investigations to identify what was going on, and what could be done to fix it. A collaboration between the McGehee group (at the ��ý��) and the Barile Group (at the University of Nevada) set out to find out exactly what was happening. The team decided to look closer, using a combination of high-powered x-rays and electrochemical tests. The windows were using tiny “seeds” of platinum to help the silver grow on the glass. Platinum is recognized for being tough and non-reactive, and so should be perfect as a nucleation point for the silver. Using these advanced techniques the team explored exactly what was happening to the platinum seeds during the clearing phase, when the silver “paint” is stripped away.

To their surprise, the platinum was not as tough as they initially thought. In the special liquid environment needed for the windows, the platinum seeds were actually dissolving and washing away when the window was switched to clear. As the number of seeds dropped, the silver had fewer locations to grow from, which was the cause behind the window tinting slowing.

This led the team to ask the question “What can we do to make the seeds more resilient?”, which led them to use gold in place of platinum. While gold and platinum are both precious metals, in water, which is the solvent used inside the window panels, gold is more stable and less susceptible to decomposition and dissolving. When they swapped the platinum seeds for gold ones, the results were immediate. Even after 7,500 cycles, the equivalent of years of daily use, the windows transitioned just as fast as the first time they were used.

These gold-based windows provide an exciting range of opportunities. Not only because of their improved stability over many thousands of cycles, but also because they can express multiple colors by varying the voltage, a feature of the size of the gold particles. This presents opportunities for their use in displays and communications devices. This technology offers a better, smarter window that could passively save significant amounts of energy if deployed in commercial and residential buildings. This work shows how the impact of making fundamental chemical changes can unlock the potential of new technologies.

January 2026

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Influence of Ligand Exchange on Single Particle Properties of Cesium Lead Bromide Quantum Dots

Daniel Morton — Tue, 20 Jan 2026 21:16:48 +0000

Influence of Ligand Exchange on Single Particle Properties of Cesium Lead Bromide Quantum Dots Daniel Morton Tue, 01/20/2026 - 14:16

CHEMISTRY OF MATERIALS, 2026, ASAP

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Nickel-oxide hole-transport layers prevent abrupt reverse-bias breakdown and permanent shorting of perovskite solar cells caused by pinhole defects

Daniel Morton — Tue, 13 Jan 2026 00:25:38 +0000

Nickel-oxide hole-transport layers prevent abrupt reverse-bias breakdown and permanent shorting of perovskite solar cells caused by pinhole defects Daniel Morton Mon, 01/12/2026 - 17:25

EES SOLAR, 2026, ASAP

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Polariton Control of Molecular Charge Transfer in Perylene Diimide Semiconductors

Daniel Morton — Thu, 08 Jan 2026 00:22:26 +0000

Polariton Control of Molecular Charge Transfer in Perylene Diimide Semiconductors Daniel Morton Wed, 01/07/2026 - 17:22

THE JOURNAL OF PHYSICAL CHEMISTRY LETTERS, 2026, ASAP

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Photophysical Properties and Phase Behavior of Ultrawide Photovoltaic Bandgap Cesium–Lead-Based Triple Halide Perovskites

Daniel Morton — Tue, 06 Jan 2026 00:19:00 +0000

Photophysical Properties and Phase Behavior of Ultrawide Photovoltaic Bandgap Cesium–Lead-Based Triple Halide Perovskites Daniel Morton Mon, 01/05/2026 - 17:19

CHEMISTRY OF MATERIALS, 2026, ASAP

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Locking in Solar Power: How a Stronger Interlayer Boosts Perovskite Cell Durability

Daniel Morton — Mon, 05 Jan 2026 19:31:00 +0000

Locking in Solar Power: How a Stronger Interlayer Boosts Perovskite Cell Durability Daniel Morton Mon, 01/05/2026 - 12:31

New Molecular Designs Extend the Life and Efficiency of Next-Generation Solar Cells

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Posted on the RASEI website with permission and minor modifications from the piece published by David DeFusco on the UNC Chapel Hill Applied Physical Sciences Site here.

A new study published in Science led by researchers at UNC-Chapel Hill, with collaborators from the Renewable and Sustainable Energy Institute (RASEI), explains why perovskite solar cells—fast-rising rivals to traditional silicon panels—tend to break down under prolonged heat and sunlight, especially ultraviolet light, and reveals a promising strategy to dramatically slow that damage.

The work focuses on a thin “interlayer” that sits between the electrode and the perovskite material inside a solar cell. This layer is only a single molecule thick, but it plays an outsized role in how long the device lasts.

“These interlayers are meant to help charges move efficiently out of the perovskite and into the circuit,” said Chengbin Fei, first author of the study and a postdoctoral researcher in UNC’s Department of Applied Physical Sciences. “But we found that some of the same chemical features that make them useful can also cause long-term damage if they’re not tightly attached to the electrode.”

Many high-performance perovskite solar cells use interlayers based on phosphonic acids. These molecules stick to a transparent electrode made of indium tin oxide, or ITO, and help pull positive charges out of the perovskite. Until now, most researchers assumed these layers were harmless once installed. Fei and his colleagues discovered that this is not always true.

The researchers found that some of these tiny helper molecules aren’t firmly stuck to the solar cell’s surface. When the cell gets hot or sits in sunlight that includes ultraviolet rays, those that are loosely attached molecules can break free. Once that happens, they start interfering with the solar material itself. They trigger harmful changes inside the cell: key ingredients fall apart, iodine-related components react in damaging ways and lead turns into a form that no longer works properly. Over time, all of this damage adds up and causes the solar cell to produce less and less electricity.

“In simple terms, the acid part of these molecules can act like a slow poison,” said Fei. “At high temperatures and under UV light, it accelerates chemical reactions that the perovskite just can’t tolerate.”

To understand what was happening, the researchers used a range of techniques, including spectroscopy and X-ray measurements, to watch how the materials changed over time. They found that stronger acids caused faster damage and that UV light made the reactions much worse. This explained why devices that look stable at first can fail after hundreds or thousands of hours outdoors.

The key advance came when the researchers at UNC and the ��ý�� created a new version of this thin helper layer containing a combination of two molecules that sticks much more tightly to the electrode surface. Seth Marder, the senior author at the University of Colorado-��ý�� and Director of the Renewable and Sustainable Energy Institute (RASEI) says “the molecule our team developed was designed to not only interact with the electrode surface but more strongly with its neighboring molecules. Consequently the molecules stay more securely in place, reducing the reactive parts that can break away and damage the solar material that is deposited on top ”. As a result, the layer still helps charges flow out of the cell, but it no longer triggers the damaging reactions that shorten the cell’s lifetime.

Simply put, “when the molecule is firmly locked onto the surface, it can’t wander into the perovskite and cause trouble,” said Fei. “That simple change makes a huge difference over time.”

Solar cells made with the new interlayer design showed striking improvements and met a key performance milestone. Under harsh test conditions—85 degrees Celsius, continuous bright light that included UV and constant operation—the devices ran for nearly 3,000 hours before losing just 10 percent of their efficiency. That level of durability has not been reported before for this type of perovskite solar cell.

The molecule our team developed was designed to not only interact with the electrode surface but more strongly with its neighboring molecules. Consequently the molecules stay more securely in place, reducing the reactive parts that can break away and damage the solar material that is deposited on top.
- Seth Marder

The researchers also scaled up their approach to small solar modules, closer to what might be used in real products. These “minimodules,” about the size of a postcard, reached power conversion efficiencies above 22 percent and kept working for more than 2,000 hours under the same stressful conditions, which is considered very high performance for this type of solar technology.

Jinsong Huang, senior author of the paper and UNC Louis D. Rubin Distinguished Professor, said the results address one of the most important barriers to commercialization. “Efficiency alone is not enough,” he said. “For perovskite solar technology to succeed outside the lab, it must survive heat, light and time. This work shows a clear chemical pathway to make that happen.”

Beyond improving one specific material, the study sends a broader message to the field. Tiny details at buried interfaces—places that are hard to see and easy to overlook—can control the lifetime of an entire solar module. By understanding and managing these details, researchers can design devices that last far longer.

“This study reminds us that stability is a chemistry problem as much as an engineering one,” said Wei You, a co-author of the study and UNC Cary C. Boshamer Distinguished Professor of Chemistry and Applied Physical Sciences. “Once you understand the chemistry, you can start to fix it.”

January 2026

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Limiting phosphonic acid interlayer–perovskite reactivity to stabilize perovskite solar modules

Daniel Morton — Fri, 02 Jan 2026 00:02:56 +0000

Limiting phosphonic acid interlayer–perovskite reactivity to stabilize perovskite solar modules Daniel Morton Thu, 01/01/2026 - 17:02

SCIENCE, 2026, 391, 6780, eadz7969

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Platinum–Ruthenium Alloys Are Not Bifunctional CO Electro-Oxidation Catalysts: A Kinetic Analysis

Daniel Morton — Wed, 24 Dec 2025 00:10:35 +0000

Platinum–Ruthenium Alloys Are Not Bifunctional CO Electro-Oxidation Catalysts: A Kinetic Analysis Daniel Morton Tue, 12/23/2025 - 17:10

ACS ENERGY LETTERS, 2025, 11, 1, 664-672

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Assessing the Long-Term Stability of Anion Exchange Membranes for Electrochemical CO2 Reduction

Daniel Morton — Wed, 24 Dec 2025 00:06:34 +0000

Assessing the Long-Term Stability of Anion Exchange Membranes for Electrochemical CO2 Reduction Daniel Morton Tue, 12/23/2025 - 17:06

ACS APPLIED ENERGY MATERIALS, 2025, 9, 1, 359-371

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Fusion and fission of particle-like chiral nematic vortex knots

Daniel Morton — Mon, 15 Dec 2025 18:53:44 +0000

Fusion and fission of particle-like chiral nematic vortex knots Daniel Morton Mon, 12/15/2025 - 11:53

NATURE PHYSICS, 2025

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