[en] For the first time, a series of TiO₂ complex flakes with edged-curled derived from MAX (denoted as TOC) are successfully prepared through simple and practical cold-quenching pretreatment in liquid nitrogen combined with thermal treatment of MAX flakes etched for various hours and peeled off. When investigated as anodes in lithium ion batteries (LIBs), compared with other TLC-TOC flakes tested, TLC-TOC24 electrode presents the highest discharge capacity in the second cycle of 559.4 mAh g⁻¹ and more than 94% of the capacity after 835 cycles at 0.1 A g⁻¹. When the applied current is changed to 3 A g⁻¹, the reversible specific capacity of TLC-TOC24 remains 150 mAh g⁻¹ after 10000 cycles. Such an excellent cyclic stability is predominantly ascribes to the highway applied by meso/micro-pores for electroactive ions migration, the existence of Al element is benefit for obtaining mesoporous TLC-TOC24 with high specific capacitance. Furthermore, the pseudocapacitive behavior of TLC-TOC24 also remarkably breaks the dynamic ceiling effect of the solid-state diffusion process. Therefore, because of the simplicity, operability and industrialization of cold quenching technique in liquid nitrogen and outstanding electrochemical performance, mesoporous TLC-TOC24 is expected to become negative material for LIBs.

[en] Highlights: • Nanowire PProDTM free-standing film was prepared by template-free method. • The PProDTM achieved 99.6 F g⁻¹ at 1.0 A g⁻¹ in ACN containing 0.1 M Bu₄NBF₄. • The solid-state device based on PProDTM exhibited good redox property and stability. Nanowire poly (3,4-dihydro-2H-thieno [3,4-b] [1,4]dioxepin-3-yl)methanol (PProDTM) free-supporting films with conductivities around 1.92 S cm⁻¹ were prepared using a template-free electropolymerization method. The structure, morphology, mechanical properties, and thermal stability of the PProDTM films were characterized by Fourier transform infrared spectroscopy, UV–vis spectroscopy, scanning electron microscopy, dynamic mechanical analysis and thermogravimetric analysis. Moreover, the capacitance performances of PProDTM films were investigated in aqueous and organic electrolytes (acetonitrile (ACN) and dichloromethane (DCM)). In 0.1 M H₂SO₄, a symmetrical supercapacitor based on PProDTM exhibited specific capacitance of 89.2 F g⁻¹ at a current density of 1.0 A g⁻¹, an energy density of 3.1 Wh kg⁻¹ at power density of 0.5 kW kg⁻¹ and the cycling capacitance retention was 74.8% after 5000 cycles. As the scan rate and current density increased, the specific capacitance of PProDTM films clearly decreased in DCM, but no obvious changes occurred in water and ACN. In ACN containing 0.1 M Bu₄NBF₄, a symmetrical supercapacitor based on PProDTM exhibited specific capacitance of 99.6 F g⁻¹ at a current density of 1.0 A g⁻¹, an energy density of 3.5 Wh kg⁻¹ at power density of 0.5 kW kg⁻¹ and the cycling capacitance retention was 82.2% after 5000 cycles. These results imply that our flexible free-supporting PProDTM films are promising for future use in supercapacitors.