Mechanically strong, transparent, and biodegradable wood-derived film

Plastics with excellent mechanical flexibility and optical properties have been widely used as substrates in flexible electronics and optoelectronics. However, the intrinsic conflicts among the poor accessibility and adverse environmental impacts limit the further development of plastics. Development of sustainable alternatives with competitive properties to replace synthetic plastics is urgently needed. Here, we propose a feasible and effective strategy with a micro/nanoscale structure design to convert bulk natural wood into a high-performance wood film with a high optical transmittance (77% at 550 nm) and high haze (73.5%). The resulting transparent wood films (TWF) exhibited a high tensile strength of 426 MPa. Moreover, the TWF had a lower environmental impact as it can be easily recycled and biodegraded under natural conditions. The unique characteristics make it a low-cost, high-performance, sustainable, and biodegradable alternative for flexible electronics, humidity sensors, and optical management devices.