Henrik Soensteby holds a silicon wafer covered with a thin film consisting of sodium, potassium, niobium and oxygen. The colors are caused by unintentional thickness variations. Credit: Bjarne Roesjoe/UiO
Most smartphones and other electrical or electronic products contain small amounts of lead, which doesn’t sound like a big problem on its own. But when there are many billions of such products, either in daily use or gone astray, the total sums up to very large amounts of lead – which is a toxic heavy metal.
Therefore, the environmental authorities in the EU/EEA, the USA and several other countries have agreed to limit the use of lead in electrical and electronic equipment. Products must contain no more than 0.1 per cent by weight of lead in order to be approved for CE marking, according to current regulations – but there are exceptions, especially when there are no alternative materials to be found.
A long step in the non-toxic direction
“In practice, it is not possible to limit or stop the use of lead in such products if you don’t have other materials that can deliver the same benefits without being significantly more expensive. Therefore, we at the Department of Chemistry at the University of Oslo (UiO) have tried to develop new materials that can replace the lead-containing materials. Now, we have taken a long step in a right and non-toxic direction,” says researcher Henrik Hovde Soensteby to Titan.uio.no.
Soensteby recently graduated as a PhD, based on his work on making thin films of a material that has the potential to replace lead in electrical and electronic products. The material contains the common elements sodium, potassium and oxygen in addition to the metal niobium, and has no known harmful environmental effects.
“Strictly speaking, the material isn’t completely new, but it has been difficult to produce it on a form that can be used in applications. But now, we have solved this problem by using the technique called Atomic Layer Deposition (ALD). We are now able to make thin films with potassium and sodium as important ingredients, which is something nobody else has been able to do earlier,” Soensteby explains
The problem with lead
The background for Sønsteby’s research is that we are buying ever more electrical and electronic products, which for a large part end up as Waste Electrical and Electronic Equipment (WEEE) when new and cooler gadgets become available. This means that the amount of WEEE is constantly increasing worldwide, because some nations aren’t as clever as Norway when it comes to recycling. According to the Norwegian Environment Agency, about 85 percent of the WEEE in Norway is recycled and used in the production of new equipment.