Chinese scientists have developed a device for wastewater treatment while generating energy. article about it published At the Frontiers of Environmental Science and Engineering.
In recent years, humanity has faced two problems at once: the need to switch to renewable energy sources and to clean the environment from the waste of civilization. While wastewater contains a lot of organic pollutants, decomposing them can provide up to three times more energy than is required for treatment. The difficulty lies only in how to obtain this energy.
In this context, experts from Tsinghua University proposed a photocatalytic fuel cell design. In it, electron-hole pairs are formed at the anode under the influence of light. As pollutants oxidize and are separated by “holes”, electrons from the anode can pass from the external circuit to the cathode and create a current. The proposed design is based on bismuth oxide chloride (BiOCl) because its layered structure accelerates the separation and migration of electron-hole pairs, moreover, the high photocatalytic activity contributes to the decomposition of various persistent organic pollutants in wastewater.
The fuel cell uses BiOCl in combination with polyoxometalate (NH 4PTA), which acts as a photoelectron acceptor and promotes the decomposition reaction by slowing the recombination of photogenerated electrons and holes. During the experiments it turned out that almost 100% of the pollutants can decompose within 90 minutes of exposure.
The authors hope that their device could be used for wastewater treatment by at least partially recovering the spent energy.
Earlier Siberian scientists to create The way to detect latent obesity in children.