Micro‐Structural and Flexible Reduced Graphene Oxide/Ti₃C₂T_x Composite Film Electrode with Long Cycle Life for Supercapacitor

Abstract

Poor rate capability due to the sheet self‐stacking of conventional MXene electrode limits their electrochemical application to some extent. Herein, incorporating reduced graphene oxide into Ti3C2Tx MXene is reported to improve the electrochemical performance, cycle lifetime, and mechanical flexibility significantly. Graphene oxide is reduced by thermal heating, by which it can release gas locally to induce micro‐surface structure. The resulting film with an introduction of 20 wt% graphene oxide exhibits an expansion of the interlayer space to multiply the active sites and thereby lead to a specific capacitance of up to 322 F g−1 at 1 A g−1 in 3 m H2SO4 electrolyte. In addition, the fabricated composite electrode also exhibits an excellent cycle stability and mechanical flexibility even after 32 000 charge/discharge cycles. This work provides a progressive strategy to synthesize micro‐structural and flexible MXene‐based electrode for the future application in flexible energy storage devices.

High-Capacitance γ-rGO/MXene Cathode and Rapid Na+-Transfer Dynamics Sodium Titanate Anode for a Quasi-Solid-State Sodium-Ion Capacitor

“…The appearance of the (002) plane characteristic peak of γ-rGO at 24° proves the efficient reduction of γ-irradiation. , Compared with the multiple sharp characteristic peaks of MAX (JCPDS: 29–0101), V 2 C retained the (002) plane characteristic peak located at 2θ = 7.4°, indicating the successful etching and delamination of MXene. , The corresponding characteristic peaks of γ-rGO in GMF after adding V 2 C still exist, indicating that γ-rGO is the main framework in GMF. Similar to V 2 C, GMF also exhibits a (002) peak at 2θ = 7.4°, indicating an interlayer spacing of 1.71 nm, which is consistent with that seen by AFM. , …”

“…Similar to V 2 C, GMF also exhibits a (002) peak at 2θ = 7.4°, indicating an interlayer spacing of 1.71 nm, which is consistent with that seen by AFM. 25,43 The XPS test further illustrates the elemental composition of V, C, and O and the chemical bonding states in GMF (Figure S4). The high-resolution C 1s spectra of GMF can be deconvoluted into five components (Figure 1g 23,44 The V 2p level spectrum of GMF could be deconvoluted into three doublets, which are attributed to V−C/V 4+ (517.2 eV), V 3+ (514.5 eV), and V−O/V 2+ (513.7 and 521.3 eV) (Figure 1h).…”

3D Porous Compact 1D/2D Fe2O3/MXene Composite Aerogel Film Electrodes for All‐Solid‐State Supercapacitors

“…For the high‐resolution spectum of C 1s ( Figure a), four components centered at 281.7, 284.6, 285.1, and 288.9 eV can be assigned to CTi, CC, CO, and OCO bonds, respectively. [ 8 ] For Ti 2p spectrum (Figure 4b), three doublets (Ti 2p 3/2 Ti 2p 1/2 ), which are fitted at 455.0, 456.2, 458.9, 460.7, 461.9, and 464.4 eV, can be assigned to TiC 2p 3/2 , TiX 2p 3/2 , TiO 2p 3/2 , TiC 2p 1/2 , TiX 2p 1/2 , and TiO 2p 1/2 bonds, respectively. [ 40,41 ] For Fe 2p spectrum (Figure 4c), showing two main peaks at 710.9 and 724.5 eV and two satellite peaks at 715.8 and 729.4 eV, which can be assigned to Fe 3+ characteristic peaks in hematite.…”

“…[4][5][6][7] However, 2D MXene nanoflakes usually suffer from serious re-stacking due to the intense van der Waals force, which reduces the effective active sites and ion transport channels. [8] In order to avoid this tendency and improve the electrochemical performance of film electrodes, a series of interesting strategies has been reported and carried out. For example, introducing the second phase among the interlayer of MXene, such as noble metal nanoparticle (Au, Ag, Pt, etc.…”

Recent Research Progress in the Structure, Fabrication, and Application of MXene-Based Heterostructures

“…The low-rate performance caused by the sheet self-stacking of the traditional MXene electrode limits its electrochemical application to a certain extent. Luo et al [ 95 ] reported the preparation of a reduced graphene oxide/Ti 3 C 2 T x electrode for a supercapacitor. The fabricated composite electrode exhibited outstanding electrochemical performance and mechanical flexibility, and still maintained excellent cycle stability after 32,000 charge-discharge cycles.…”