Sunlight can cause a molecule to change structure, and then release heat later.
Category: sustainability
Physicists explain the exceptional energy-harvesting efficiency of perovskites
Despite being riddled with impurities and defects, solution-processed lead-halide perovskites are surprisingly efficient at converting solar energy into electricity. Their efficiency is approaching that of silicon-based solar cells, the industry standard. In a new study published in Nature Communications, physicists at the Institute of Science and Technology Austria (ISTA) present a comprehensive explanation of the mechanism behind perovskite efficiency that has long perplexed researchers.
How can a device assembled with minimal sophistication rival state-of-the-art technology perfected over decades? Over the past 15 years, materials research has witnessed the rise of lead-halide-based perovskites as prospective next-generation solar-cell materials. The puzzle is that despite similar performance, perovskite solar cells are fabricated using inexpensive solution-based techniques, while the industry-standard silicon cells require ultra-pure single-crystal wafers.
Now, postdoc Dmytro Rak and assistant professor Zhanybek Alpichshev at the Institute of Science and Technology Austria (ISTA) have uncovered the mechanism behind the unique photovoltaic properties of perovskites. Their key finding is that while silicon-based technology relies on the absence of impurities, the opposite is true in perovskites: It is the natural network of structural defects in these materials that enables the long-range charge transport necessary for efficient photovoltaic energy harvesting.
New nanohole-based microscopy monitors electrochemical reactions millisecond by millisecond
Many technological applications, such as sensors and batteries, greatly rely on electrochemical reactions. Improving these technologies depends on understanding how electrochemical reactions work. However, most current methods cannot look at electrochemical reactions in detail.
Scientists at Utrecht University have now developed a new method that overcomes this limitation. This provides a powerful new way to study and improve electrochemical processes. The study is published in PNAS.
Hydrogen production by water electrolysis is one example where electrochemical reactions at electrodes matter for sustainable technology. But the decisive steps happen within just a few nanometers of the electrode surface, which is too small for most conventional methods to resolve.
Elon Musk reveals his most ambitious (and detailed) plan for Mars: 1,000 spacecraft, 20 years of launches, and a self-sustaining city of one million inhabitants on Mars by 2050
At the entrance to Starbase in south Texas, a glowing sign now welcomes visitors with the words “Gateway to Mars.” The display sits in front of SpaceX facilities where giant Starship rockets are being assembled with one bold purpose in mind: Elon Musk wants to build a self-sustaining city on Mars.
In recent years he has begun to put numbers on that dream. Musk has repeatedly said that building the first sustainable city on Mars would require around 1,000 Starship rockets and roughly 20 years of launch campaigns, moving up to 100,000 people per favorable Earth-Mars alignment and eventually reaching about one million settlers plus millions of tons of cargo.
It sounds like science fiction with a project plan. Yet the language he uses, “sustainable city,” is very familiar to climate and energy experts here on Earth. So what does sustainability really mean on a frozen, air-thin world and how does that huge effort interact with the environmental crisis on our own planet?
Microscopic robots that sense, think, act, and compute
Extremely cool paper describing optically programmable ~0.3 mm robots with onboard computation and autonomous locomotion! These tiny rectangular machines carry solar cells, optical receivers, electrokinetic actuators, and more. As demonstrations, the authors programmed them (i) to report local temperature by doing a coded dance and (ii) swim towards warmth before stopping and rotating upon reaching a location with a certain level of heat. This is amazing and I hope such devices are further improved so they can be used in biological applications! Love it!
(https://www.science.org/doi/10.1126/scirobotics.adu8009)
Autonomous submillimeter robots are built with onboard sensing, computation, memory, communication, and locomotion.
Lithium alternatives? Calcium-ion batteries show strong 1,000-cycle performance in new test
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.
How SpaceX and XAI Will Build Moonbase Alpha and Mass Drivers
SpaceX, in collaboration with xAI, plans to build a lunar base called Moonbase Alpha using advanced technologies such as mass drivers, solar power, and Starship, aiming to make human activity on the moon visible, affordable, and sustainable ##
## Questions to inspire discussion.
Launch Infrastructure Economics.
🚀 Q: What launch costs could SpaceX’s moon infrastructure achieve? A: Mature SpaceX moon operations could reduce costs to $10/kg to orbit and $50/kg to moon surface, enabling $5,000 moon trips for people under 100kg (comparable to expensive cruise pricing), as mentioned by Elon Musk.
⚡ Q: How could lunar mass drivers scale satellite deployment? A: Lunar mass drivers using magnetic rails at 5,600 mph could launch 10 billion tons of satellites annually with 2 terawatts of power, based on 2023 San Jose State study updating 1960s-70s mass driver literature.
Starship Capabilities.
Organic molecule stores solar energy for years, then releases it as heat on demand
When the sun goes down, solar panels stop working. This is the fundamental hurdle of renewable energy: how to save the sun’s power for a rainy day—or a cold night. Chemists at UC Santa Barbara have developed a solution that doesn’t require bulky batteries or electrical grids. In a paper published in the journal Science, Associate Professor Grace Han and her team detail a new material that captures sunlight, stores it within chemical bonds and releases it as heat on demand.
The material, a modified organic molecule called pyrimidone, is the latest advancement in molecular solar thermal (MOST) energy storage.
“The concept is reusable and recyclable,” said Han Nguyen, a doctoral student in the Han Group and the paper’s lead author.
Water-based electrolyte helps create safer and long-lasting Zn-Mn batteries
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.