Coplanar energy storage devices with interdigitated electrodes have attracted a significant amount of attention as micropower units for portable and flexible electronics, and self-powered systems. Herein, we propose a simple, cost-effective, and scalable two-step screen-printing process to fabricate flexible coplanar asymmetric microscale hybrid device (MHD) with a higher energy density compared to carbon-based microsupercapacitors. 2D titanium carbide MXene (Ti 3 C 2 T x) with a large inlayer spacing is selected as negative electrode, and CoAl layered double hydroxide (LDH) nanosheets are selected as positive electrode. The assembled coplanar, all-solid-state, asymmetric MHD possesses a higher energy density (8.84 μWh cm-2) compared to the MXene-based, coplanar, symmetric microsupercapacitors (3.38 μWh cm-2), and exhibit excellent flexibility and reliability, as well as cycling stability (92% retention of the initial capacitance after 10,000 cycles). Moreover, we integrate the coplanar asymmetric MHDs with the force sensing resistors as portable power source units to fabricate lightweight and inexpensive integrated force sensors, which can be used to detect applied pressure variation. The two-step screen-printing method can also be extended to other MXenes and various positive electrode materials for fabrication of coplanar asymmetric MHDs on flexible substrates. Therefore, we believe that the two-step screen-printing method opens up new avenues toward developing flexible coplanar asymmetric MHDs, thus promoting the application of MHDs based on MXenes for flexible integrated electronic devices.
Two-dimensional transition-metal carbides called MXenes are emerging electrode materials for energy storage due to their metallice lectrical conductivity and low ion diffusion barrier.I nt his work, we combinedT i 2 CT x MXene with graphene oxide (GO) followed by at hermalt reatment to fabricate flexible rGO/Ti 2 CT r film, in which electrochemically active rGO and Ti 2 CT r nanosheets impedet he stacking of layers and synergistically interactp roducing ionically and electronically conducting electrodes. The effect of the thermal treatment on the electrochemical performance of Ti 2 CT x is evaluated. As anode for Li-ion storage, the thermally treated Ti 2 CT r possesses ah igherc apacity in comparison to asprepared Ti 2 CT x .T he freestanding hybrid rGO/Ti 2 CT r films exhibit excellent reversible capacity (700 mAh g À1 at 0.1 Ag À1 ), cycling stability and rate performance. Additionally,f lexible rGO/Ti 3 C 2 T r films are made using the same method and also present improved capacity.T herefore, this study providesa simple, yet effective, approach to combine rGO with different MXenes, which can enhancet heir electrochemical properties for Li-ion batteries.[a] Dr.
scite is a Brooklyn-based organization that helps researchers better discover and understand research articles through Smart Citations–citations that display the context of the citation and describe whether the article provides supporting or contrasting evidence. scite is used by students and researchers from around the world and is funded in part by the National Science Foundation and the National Institute on Drug Abuse of the National Institutes of Health.