Graphene oxide anchored ZnO composites for enhanced piezoelectric catalytic nitrogen fixation and dye degradation

Utilizing mechanical energy to drive the reduction of N2 into ammonia faces significant challenges, such as limited N2 adsorption and activation, along with poor separation of piezo-generated charge carriers. In this study, graphene oxide (GO) layers were grafted onto the piezoelectric material ZnO using a hydrothermal method, enabled by electrostatic interactions between their oppositely charged surfaces. The ZnO-GO composites demonstrate significant efficiency in piezo-catalytic N2 fixation in pure water under ambient conditions. The optimal sample achieves an NH3 yield of 18.4 mu mol/L in 5 hours, which is 2.2 times greater than that of the original ZnO. It was found that the GO layers as cocatalysts not only enhanced electron separation from ZnO, but also facilitated the chemical adsorption and activation of N2. Additionally, the ZnO-GO catalyst was applied to the piezo-catalytic degradation of RhB, showing superior activity compared to ZnO alone. This study underscores the synergistic interactions between ZnO and GO, offering new pathways for environmentally friendly and sustainable ammonia production and water purification.