0D–1D–2D\nMultidimensional Heterostructure\nFilms for High-Performance Flexible Microsupercapacitors

Planar microsupercapacitors (MSCs) are of great value\nfor flexible\nand wearable electronics. The rational design of electrode materials\nwith rapid ionic kinetics and sufficient active site exposure is critical\nbut challenging for realizing high-energy MSCs. Herein, we report\nthe dot-tube-sheet multidimensional heterostructure films (MHFs) with\nversatile patterns by a simple mask-assisted strategy, consisting\nof 0D carbon dots (CDs), 1D carboxyl-carbon nanotubes (c-CNTs), and\n2D Ti<sub>3</sub>C<sub>2</sub> MXene nanosheets. Thanks to the high\nelectrical conductivity, enlarged interlayer spacing, abundant porous\nchannels, and excellent mechanical strength, the CDs/c-CNTs/Ti<sub>3</sub>C<sub>2</sub> MHF electrodes deliver a remarkable areal capacitance\nof 1162.6 mF cm<sup>–2</sup> at 0.8 mA cm<sup>–2</sup> and prominent cycling stability (107.1% capacitance retention after\n10,000 cycles) in a 1 M H<sub>2</sub>SO<sub>4</sub> electrolyte. Moreover,\nthe fabricated solid-state CDs/c-CNTs/Ti<sub>3</sub>C<sub>2</sub> MSCs\nachieve a high energy density (11.1 mWh cm<sup>–2</sup>) and\nlong-term cycling lifespan (102.1% capacitance retention after 8000\ncycles), superior to those of state-of-the-art MSCs. The parallel\nand serial interconnected modular power sources highlight the potential\nfor powering the actual energy consumption products.