Most electronic gadgets run on batteries, which in time need to be replaced and can be bulky. Solar power is a possible alternative, but the sun doesn't always shine when devices need to work. Artificial room lighting, however, is all around - in homes, schools, offices, stores - and can be controlled on demand.
A team of researchers have developed special light harvesters, like those used for solar power, optimised to produce energy from ambient indoor lighting. The work is described in ACS Applied Materials & Interfaces.
To put room lighting to work, Ryota Arai, Takuma Yasuda and colleagues turned to organic photovoltaics (OPVs), which are light, flexible and transparent.
To determine the best configuration for OPVs, the researchers tested small-molecule organic semiconductors that appeared to have promising characteristics for harvesting ambient light. OPVs based on the small molecule called BDT-2T-ID outperformed other similar devices, even one based on silicon solar technology. A set of six of these devices connected in series could produce about 4 volts under dim illumination to power microsensors, according to the team.
Much needs to be done to scale up the technology, but the team says it could someday be a viable way to power wireless devices throughout a room.