Manipulating Electrical Properties of Silica-Based Materials via Atomic Oxygen Irradiation.

Regulated triboelectrification has attracted considerable research attention due to its potential applications in harvesting energy and importance in antistatic protection. Irradiation is an effective and stable modification method due to its adjustable and uniform irradiation parameters. Moreover, atomic oxygen (AO) irradiation is an important component in the low earth orbit, which is a considerable factor for promoting triboelectric nanogenerators (TENGs) in the outer space. AO irradiation was utilized to manipulate the surface structure and chemical composition to regulate electrical properties. AO irradiation can increase electron-donating groups and enhance electrical positivity of polydimethylsiloxane (PDMS) films due to the transition from Si-C bonds to Si-O bonds. Therefore, different trends of polytetrafluoroethylene (PTFE) and polystyrene (PS) were caused by their TENG composition with irradiated PDMS. Tribocharge cross-over polarity and charge generation were prevented completely in PS- and PDMS-based TENGs by adjusting the irradiation time to 4.1 h. Short-circuit current enhanced from 5 to 22 μA and the output voltage increased from 160 to 760 V when PDMS films in PTFE- and PDMS-based TENGs were subjected to AO irradiation for 6 h. This study demonstrated that AO irradiation can manipulate triboelectric properties of silica-based materials, which are potential components for harvesting energy and preventing electrostatic hazard in the outer space.