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.
Ao longo dos anos, os cientistas investigaram uma série de soluções inovadoras de pisos capazes de gerar eletricidade a partir do movimento humano, incluindo telhas cerâmicas para uso interno e externo e madeira esponjosa que depende do efeito piezoelétrico para gerar tensão sob pressão mecânica. Este novo exemplo compartilha algumas semelhanças com outro que vimos em 2016, em que os cientistas incorporaram nanofibras de celulose em pisos de madeira, criando uma carga elétrica quando vibrada através do chamado efeito triboelétrico.
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.
Segundo os cientistas, esse tratamento torna a madeira 80 vezes mais eficiente na geração de eletricidade do que a madeira natural e fornece uma produção estável sob estresse constante por até 1.500 ciclos. Moldado em um piso do tamanho de um papel A4, o material pode gerar eletricidade suficiente para alimentar luzes LED domésticas, calculadoras e outros pequenos eletrônicos.
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.
