Core Insights - The research team led by Liu Gang from the Institute of Metal Research, Chinese Academy of Sciences, has developed a new strategy combining "floating strategy" and "dimensional customization," enabling titanium dioxide to float on the surface of neutral aqueous solutions, providing a competitive alternative for plastic conversion [1][2] - China, as the world's largest producer and consumer of plastics, generates over 60 million tons of plastic products annually, with waste plastic reaching 43 million tons, posing significant threats to the environment, ecosystems, and human health [1] - Photocatalytic reforming technology has emerged to decompose plastics into high-value chemicals using semiconductor materials activated by sunlight, representing both solid waste recycling and energy conversion [1] Technology Development - The Liu Gang team has created a nanometer-scale carbon-nitrogen hydrophobic layer on the surface of two-dimensional titanium dioxide, allowing it to float on neutral aqueous solutions [2] - This new material forms a four-phase interface with photocatalytic materials, plastics, water, and air, reducing the interface distance to molecular levels, thus enhancing the reaction efficiency [2] - Unlike traditional photocatalytic systems that primarily utilize photogenerated holes to oxidize water molecules, the floating titanium dioxide material uses photogenerated electrons to reduce oxygen, producing superoxide radicals with a lifespan of up to 1 millisecond, significantly increasing the operational radius for breaking down plastic carbon chains [2] Performance Improvement - The floating titanium dioxide material demonstrates superior photocatalytic performance, achieving a 1 to 2 orders of magnitude increase in the reforming efficiency of typical plastics such as polyethylene, polypropylene, and polyvinyl chloride without relying on corrosive solution pretreatment [2] - The new material also produces over 40% selective high-value ethanol products, setting a new record for reforming efficiency under neutral conditions [2]