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Say cheese, get gold.

Many electronic devices, such as smartphones, computers, and televisions, contain small amounts of gold in components like connectors, circuit boards, and integrated circuits, but they are usually considered electronic waste.


Uncover the innovative use of whey protein to extract gold from electronic waste. A sustainable and efficient solution for reducing e-waste.

There is no doubt that water is significant. Without it, life would never have begun, let alone continue today—not to mention its role in the environment itself, with oceans covering over 70% of Earth.

But despite its ubiquity, liquid water features some electronic intricacies that have long puzzled scientists in chemistry, physics, and technology. For example, the , i.e., the energy stabilization undergone by a free electron when captured by water, has remained poorly characterized from an experimental point of view.

Even today’s most accurate electronic structure has been unable to clarify the picture, which means that important physical quantities like the energy at which electrons from external sources can be injected in liquid water remain elusive. These properties are crucial for understanding the behavior of electrons in water and could play a role in , environmental cycles, and technological applications like solar energy conversion.

Transforming base materials into gold was one of the elusive goals of the alchemists of yore. Now Professor Raffaele Mezzenga from the Department of Health Sciences and Technology at ETH Zurich has accomplished something in that vein. He has not of course transformed another chemical element into gold, as the alchemists sought to do. But he has managed to recover gold from electronic waste using a byproduct of the cheesemaking process.

Electronic waste contains a variety of valuable metals, including copper, cobalt, and even significant amounts of gold. Recovering this gold from disused smartphones and computers is an attractive proposition in view of the rising demand for the precious metal.

However, the recovery methods devised to date are energy-intensive and often require the use of highly toxic chemicals. Now, a group led by ETH Professor Mezzenga has come up with a very efficient, cost-effective, and above all far more sustainable method: with a sponge made from a , the researchers have successfully extracted gold from electronic waste.

The Voyager 1 was launched in 1977. Almost 50 years later, it’s still going and sending back information, penetrating ever deeper into space. It can do that because it’s powered by nuclear energy.

Long a controversial energy source, nuclear has been experiencing renewed interest on Earth to power our fight against climate change. But behind the scenes, nuclear has also been facing a renaissance in space.

In July, the US National Aeronautics and Space Administration (NASA) and Defense Advanced Research Projects Agency (DARPA) jointly announced that they plan to launch a nuclear-propelled spacecraft by 2025 or 2026. The European Space Agency (ESA) in turn is funding a range of studies on the use of nuclear engines for space exploration. And last year, NASA awarded a contract to Westinghouse to develop a concept for a nuclear reactor to power a future moon base.

Zinc-air batteries are an inexpensive, powerful battery alternative that can be used on the small scale to power electronics or on the large scale for electric vehicles or energy storage. These batteries work when oxygen from the air oxidizes zinc, but the difficulty in oxygen activation which degrades battery performance has prevented their wide commercial adoption.

Information presented in a paper published in Carbon Future (“Fullerene-metalloporphyrin co-crystal as efficient ORR electrocatalyst precursor for Zn-air batteries”) shows how the addition of fullerene-derived carbon materials as catalysts can improve performance, stability, and cost of zinc-air batteries.

This graphic illustrates a zinc-air battery can using a fullerene-metalloporphyrin co-crystal as an oxygen reduction reaction catalyst. (Image: Carbon Future, Tsinghua University Press)

Azeem speaks with Professor Yoshua Bengio. In 2018, Yoshua, Geoff Hinton and Yann LeCun were awarded the Turing Award for advancing the field of AI, in particular for their groundbreaking conceptual and engineering research in deep learning. This earnt them the moniker the Three Musketeers of Deep Learning. I think Bengio might be Aramis: intellectual, somewhat pensive, with aspirations beyond combat, and yet skilled with the blade.

With 750,000 citations to his scientific research, Yoshua has turned to the humanistic dimension of AI, in particular, the questions of safety, democracy, and climate change. Yoshua and I sit on the OECD’s Expert Group on AI Futures.