Polyoxometalate film simultaneously converts multiple low-value all-weather environmental energy to electricity

The conversion of low-value natural environmental energy into the clean and high-value electricity provides a promising approach for solving the energy crisis and environmental pollution. Using one device to directly convert all-weather environmental energy into electricity is an ideal goal and still remains a great challenge. Here, we assembled a simple and multifunctional device with the polyoxometalate (POM)/ethyl cellulose composite film on metal substrate, which generates electricity from multiple low-value all-weather environmental energy, including sunlight, wind and raindrops. For example, the optimal Mo 72 Cr 30 /ethyl cellulose composite film (Mo 72 Cr 30  wt% = 71.4%) exhibits remarkable output performance with the responsivity of 176.3 μA W −1 under AM 1.5 G solar light, an average output of 4.48 μW m −2 from wind at a speed of 10 m s −1 , and an average output of 0.25 μW m −2 from raindrops at a dripping rate of 7 mL min −1 , as well as the better output power density of 6.32 μW m −2 , 0.54 μW m −2 and 8.71 μW m −2 simultaneously driven by sunlight and wind, sunlight and raindrops, wind and raindrops, respectively. It also achieves an average output power density of 17.7 μW m −2 , as well as long-term durability when it is simultaneously driven by sunlight, wind and raindrops, which exhibits 4 and 70 times than single wind and raindrops condition. For this composite film, the maximum power density is achieved at a very low resistance load of about 10 Ω. The output power arises from the high efficient transport of photo-generated electrons and electrostatic charges from Mo 72 Cr 30 to metal substrate.