Attaching ZrO2 nanoparticles onto the surface of graphene oxide via electrostatic self-assembly for enhanced mechanical and tribological performance of phenolic resin composites

ZrO2 nanoparticles were electrostatic self-assembled on the surface of graphene oxide (GO) for enhancing the mechanical and tribological properties of phenolic resin. Zeta potential analysis and structural characterization confirmed that ZrO2 nanoparticles had been successfully adhered onto the surface of GO, and the as-prepared ZrO2@GO nanohybrid possessed good dispersity. The results showed that filling 1.5 wt% ZrO2@GO nanohybrid could improve the flexural strength, flexural modulus and impact strength of phenolic resin (PF) by 38.6%, 10.7% and 8.3%, respectively. When 0.5 wt% ZrO2@GO was added, the initial decomposition temperature and the residual content at 800 °C of PF increased by 20.0% and 16.9%, respectively. The ZrO2@GO nanohybrid also exhibited synergistic effect for improving the tribological performance of PF effectively, that when adding 0.5 wt% ZrO2@GO nanohybrid, the average friction coefficient and wear rate of the composites reduced by 21.8% and 30.6%, respectively. SEM observation and 3D non-contact surface topography analysis showed the wear surface of ZrO2@GO nanohybrid filling PF composite was smooth, low spalling and shallowly grooved with the typical characteristic of abrasive wear. It was explained that the ZrO2@GO nanohybrid could play the role of rolling bearings, form stable and smooth friction transfer film and enhance the interfacial interaction, thus indicated the synergistic wear-resisting performance for PF matrix. It provides a green, convenient and fast method for preparing ZrO2 nanoparticles-attached GO nanohybrid that can enhance the mechanical and tribological performance of resin-based materials effectively.