From CO2 to Electricity: Photosynthesis-Based Functionally Cooperating Mini-Generator

Recently, the global warming and climate changes have aroused focus of attentions. Hence, there is an increased demand to capture, utilize, and sequestrate the greenhouse gas, i.e., carbon dioxide (CO2), for promising applications. Functionally cooperating mini-generators are a kind of self-propelled smart devices that can harvest environmental energy and convert it to electricity through Faraday's law. But traditional mini-generators are based on an energy-consuming process appealing for energy consumption from high-grade state to low-grade one. Herein, a mini-generator based on photosynthesis with CO2 as the fuel is designed. The generator can convert the internal energy of O-2 bubbles produced by photosynthesis to electricity. This is an energy conversion from the lowest energy state to the applicable energy. Based on the high-efficiency photosynthesis of hydrophyte, spontaneously water-dissolved CO2 can afford to induce regularly cycled surfacing-diving motion, and the induced electrical output can simultaneously actuate multiple electronic components. Owing to the weather sensitivity of the photosynthesis, the system can be used to monitor weather through reading the changes of output electrical signals. By integrating the artificial smart device with natural plants, this research will promote the applications of miniaturized devices toward green development.