Generating energy with water and silicon

24 November 2025

Study involving researchers at TUHH and DESY verifies process that converts mechanical energy into electricity

A team of researchers involving scientists at the Hamburg University of Technology (TUHH) and the German Electron Synchrotron DESY , have come up with a a new method for generating electricity using friction. This prerequisites water, silicon and pressure. A study shows that electrical energy is generated by cyclic, impulsive penetration and escape of water into nanometre-sized silicon pores. The intrusion-extrusion triboelectric nanogenerator (IE-TENG) developed for this purpose could be used e.g., for vehicle shock absorbers which have high mechanical pressure. Researchers from Germany, Spain, Italy, Poland and Latvia were also involved in the study.

Water as an energy source

IE-TENG is based on frictional electricity, which can be felt when hair becomes electrically charged from being combed or when you get a slight electric shock. Electrons are transferred from one body to the other. Charge accumulates, which is suddenly discharged as soon as a third body is touched. In the IE-TENG, this energy is generated at the interface between the silicon pore wall and the water. The generator has achieved one of the highest efficiency values in energy conversion of comparable systems and converts up to 9 per cent of the mechanical energy into electricity, researchers said. "The combination of nanoporous silicon and water enables an efficient, reproducible energy source - without the use of exotic materials," said Dr Luis Bartoloméma, a researcher at CIC energiGUNE in Spain.

Illustration of friction and stress at nanopores on the silicon surface — © TU Hamburg

New generation of self-powered technologies

Water-powered materials represent "a new generation of self-powered technologies", the authors said. IE-TENG could open up new perspectives for autonomous, maintenance-free sensor systems without their own battery or power supply e.g., in smart textiles, robotics or water detection. It was backed by the TUHH Cluster of Excellence "Blue Mat - Water-Driven Materials", which conducts research into sustainable material systems under the influence of water.
ja/mm/pb