Ink-printed metal/graphene aerogel for glucose electro-oxidation

Three-dimensional (3D) printing has become one of the promising technologies for the development of bulk-sized nanomaterial composites for electrocatalysis. However, traditional methods such as field deposition modeling and stereolithography are not suitable for the development of functionalized materials for practical use. A large number of studies have focused on the development of the direct ink writing (DIW) printing technique for the fabrication of graphene aerogel (GA)-based electrodes with binders for electrocatalysis. Only a few studies have focused on the synthesis of GA materials from binder-free graphene oxide (GO) using the DIW 3D printing method. Here, we describe the preparation of GA-based electrodes (without size contraction) with different Pd–Pt loadings using the DIW printing method with a commercial 3D food printer. The electron microscopy results showed that a Pd–Pt/GA monolith with a high Pd–Pt loading (59.43 wt%) could be obtained. The DIW-printed Pd–Pt/GA-2 electrode showed good electrochemical performance in glucose electrooxidation (GOR), with a high output current density of 0.94 A g⁻¹ in 0.3 M glucose/1 M NaOH solution at the 3000th cycle operation (60 h). This study shows the potential of DIW-printed binder-free Pd–Pt/GA electrodes for use in fuel cell applications.