Structural-engineered V2O5/MoO3 nanocomposite scaffolds via direct ink writing 3D printing for asymmetric supercapacitors with ultrahigh areal energy density

Due to the dense and disordered distribution of nanomaterials, the bulk electrode structure hindered advancement in energy storage devices. However, 3D printing technology supported the layer-by-layer printing process displays interconnected porous structures that provided the continuous pathways for effective diffusion of ions and electrons transportation, offering the kinetic limitations typically associated with electrode thickness. Herein, a functionalized ink composed of MV0.3/AC/PVDF for both bulk and direct ink writing (DIW) printing, enabling the construction of both electrodes with customized structure in 1-layer and 2-layer configuration. In the AASC testing, the 2-layer printed AASC(3DP-2LMV0.3) revealed a significantly high areal capacity up to 1.54 C cm⁻² at 6.2 mg cm⁻² mass loading. Furthermore, the 3DP-2LMV0.3 delivered a high areal energy density 333.4 μW h cm⁻² compare to 3DP-1LMV0.3 and BMV0.3, without compromising areal power density (2.1 mW cm⁻²) at current density (1.24 mA cm⁻²), with the excellent retention of 94.8 % after 5 k charging/discharging cycles. This work highlights the potential of DIW-3D printing as a scalable approach to construct vertically aligned porous structure with thick electrode scaffolds. It offers a promising platform for advanced energy storage applications with reduced solution resistance for ion/electron transport compared to bulk electrode structures.