Producing clean hydrogen from water is often compared to storing renewable energy in chemical form, but improving the efficiency of that process remains a scientific challenge. Researchers at Tohoku University have now developed a catalyst design that helps hydrogen form more smoothly under alkaline conditions, a key step toward practical green hydrogen production.
The work is published in the journal ACS Catalysis.
PRESS RELEASE — In the everyday world, governed by classical physics, the concept of equilibrium reigns. If you put a drop of ink into water, it will eventually evenly mix. If you put a glass of ice water on the kitchen table, it will eventually melt and become room temperature.
That concept rooted in energy transport is known as thermalization, and it is easy to comprehend because we see it happen every day. But this is not always how things behave at the smallest scales of the universe.
In the quantum realm—at the atomic and sub-atomic scales—there can be a phenomenon called localization, in which equilibrium spreading does not occur, even with nothing obviously preventing it. Researchers at Duke University have observed this intriguing behavior using a quantum simulator for the first time. Also known as statistical localization, the research could help probe questions about unusual material properties or quantum memory.
For every ton of ethylene created, one ton of carbon dioxide is produced. With more than 300 million tons of ethylene produced each year, the production system has a huge carbon footprint that scientists and engineers are eager to reduce and eventually eliminate. A new device developed in Ted Sargent’s lab at Northwestern takes a step toward breaking that cycle.
The device, an electrolyzer, has three innovations. It uses electricity to create ethylene from syngas, a waste gas produced from plastic. It uses a novel material to help catalyze the reaction. And it does so in an efficient way, reducing the overall energy needed for the system.
The results, published Feb. 17 in Nature Energy, can be used with renewable energy sources to help pave the way for a greener ethylene supply chain.
Lithium-metal batteries (LMBs) are rechargeable batteries that contain an anode (i.e., the electrode through which current flows and a loss of electrons occurs) made of lithium metal. Compared to conventional lithium-ion batteries (LIBs), which power most electronic devices on the market today, LMBs could store more energy, charge faster and operate in extreme environments.
Despite their advantages, these batteries have not yet achieved their full potential and recharging them safely in short periods of time has proved challenging. In particular, enabling the fast and efficient movement of electrons and ions across the boundary between electrodes and the electrolyte, a process known as charge transfer, has proved difficult.
If charge transfer is slow, chemical reactions become sluggish, which can also lead to undesirable side reactions and prompt the formation of Li dendrites. These are essentially needle-like extensions that can adversely impact a battery’s performance, lead to its sudden failure and, in most extreme cases, result in fires or explosions.
Researchers at The Hong Kong University of Science and Technology (HKUST) have achieved a breakthrough in calcium-ion battery (CIB) technology, which could transform energy storage solutions in everyday life. Utilizing quasi-solid-state electrolytes (QSSEs), these innovative CIBs promise to enhance the efficiency and sustainability of energy storage, impacting a wide range of applications from renewable energy systems to electric vehicles.
The findings, titled “High-Performance Quasi-Solid-State Calcium-Ion Batteries from Redox-Active Covalent Organic Framework Electrolytes,” are published in the journal Advanced Science.
The urgency for sustainable energy storage solutions is growing critical worldwide. As the world accelerates its shift to green energy, the demand for efficient and stable battery systems has never been more pressing. Today’s mainstream lithium-ion batteries (LIBs) face challenges due to resource scarcity and near-limited energy density, making the exploration of alternatives like CIBs essential for a sustainable future.
Many countries worldwide are increasingly investing in new infrastructure that enables the production of electricity from renewable energy sources, particularly wind and sunlight. To make the best of these energy solutions, one should also be able to reliably store the excess energy created during periods of intense sunlight or wind, so that it can be used later in times of need.
One promising type of battery for this purpose is based on zinc-manganese (Zn-Mn) and utilizes aqueous (i.e., water-based) electrodes instead of flammable organic electrolytes. These batteries rely on processes known as electrodeposition and dissolution, via which solid materials form and dissolve on electrodes as the battery is charging and discharging.
In Zn-Mn batteries, Zn serves as the anode (i.e., the electrode that releases electrons) and manganese dioxide (MnO₂) the cathode (i.e., the electrode from which electrons are gained). A key chemical reaction prompting their functioning, known as the MnO₂/Mn²⁺ conversion reaction, typically can only occur in acidic conditions.
Researchers in China have isolated the effects of electronic friction, showing for the first time how the subtle drag force it imparts at sliding interfaces can be controlled. They demonstrate that it can be tuned by applying a voltage, or switched off entirely simply by applying mechanical pressure. The results, published in Physical Review X, could inform new designs that allow engineers to fine-tune the drag forces materials experience as they slide over each other.
In engineering, friction causes materials to wear and degrade over time, and also causes useful energy to be wasted as heat. While this problem can be mitigated through lubricants and smoother surfaces, friction can also arise from deeper, more subtle effects.
Among these is an effect which can occur at metallic or chemically active surfaces as they slide past one another. In these cases, atomic nuclei in one surface can transfer some of their energy to electrons in the other surface, exciting them to higher energy levels. This lost energy produces a drag force that increases with sliding velocity: an effect known as “electronic friction.”
