We've already seen the idea of harnessing the power of human motion to generate electricity used in many fields, including footwear, roads, and, just this week, an implantable stimulator device for treating injured tendons,media reported. One of these possibilities is a floor that can power electronic devices, and scientists at ETH Zurich have now developed an efficient form of this technology that is powerful enough to power LED light bulbs and small electronic devices.
Gjennom årene har forskere undersøkt en rekke innovative gulvløsninger som er i stand til å generere elektrisitet fra menneskelig bevegelse, inkludert keramiske fliser for innendørs og utendørs bruk, og svampaktig tre som er avhengig av den piezoelektriske effekten for å generere spenning under mekanisk trykk. Dette nye eksemplet deler noen likheter med et annet vi så i 2016, der forskere innebygde cellulosenanofibre i tregulv, og skapte en elektrisk ladning når de ble vibrert gjennom den såkalte-triboelektriske effekten.
The triboelectric effect also forms the basis for the new smart wood floor, which consists of two treated wood veneers with electrodes layered underneath. But to get the performance to the desired level, some tinkering is required to address the limited power generation capacity of wood. "Wood is basically neutral," said Guido Panzarasa, senior author of the study. "This means that wood has no real tendency to gain or lose electrons. So the challenge is to make wood able to attract and lose electrons."
The team's solution involved coating one piece of wood with a silicone that readily gains electrons on contact, and embedding metal ions and organic molecules on another piece of wood, giving it a higher propensity to lose electrons. This treatment was tested on different species of wood cut in different directions, and the team then found the most efficient option, radially cut spruce.
Ifølge forskerne gjør denne behandlingen veden deres 80 ganger mer effektiv til å generere elektrisitet enn naturlig tre, og gir en stabil ytelse under konstant stress i opptil 1500 sykluser. Formet til et gulv omtrent på størrelse med A4-papir, kan materialet generere nok strøm til å drive husholdnings LED-lys, kalkulatorer og annen liten elektronikk.
Panzarasa said: "Our focus was to demonstrate the possibility of modifying wood with a relatively environmentally friendly procedure to have a triboelectric effect. Spruce is cheap, available, and has good mechanical properties. This method of functionalization is quite Simple and scalable on an industrial level. It's just an engineering problem."
Scientists are now working to improve their handling of wood to make it more eco-friendly and easier to apply as they work towards commercial application. To their advantage, the "dynamo" maintains the natural look and durability of wood floors, which could make it an attractive option for style-conscious designers in future smart buildings.
"The ultimate goal is to understand the potential of wood, beyond those already known, and to give wood new properties for future sustainable smart buildings," said Panzarasa. The research was published in the journal Matter.
