Graphitic Carbon with MnO/Mn₇C₃ Prepared by Laser‐Scribing of MOF for Versatile Supercapacitor Electrodes

Abstract

Pseudocapacitive materials encapsulated in conductive carbon matrix are of paramount importance to develop energy storage devices with high performance and long lifespan. Here, via simple laser‐scribing, the Mn‐based metal–organic framework [EG‐MOF‐74(Mn)] is transformed into pseudocapacitive hybrid MnO/Mn7C3 encapsulated in highly conductive graphitic carbon. It is revealed that the rapid carbothermic reduction of MnO (C + MnO → C′ + Mn7C3 + CO) leads to the formation of the intermediate pseudocapacitive MnO/Mn7C3 and the concurrent catalytic graphitization of disordered carbon. This reaction produces a new type of pseudocapacitive material in the form of MnO/Mn7C3 fully embedded in highly conductive graphitic carbon. Thanks to the synergistic effect of the MnO/Mn7C3 nanoparticles and the graphitic carbon, the composite exhibits a high specific capacitance of 403 F g−1 with excellent stability. Asymmetric coin‐cell supercapacitors based on the composite demonstrate high energy (29.2 Wh kg−1) and power densities (8000 W kg−1) with a long lifespan. Prototypes of flexible paper‐based supercapacitors made of the composite also show great potential toward applications of flexible electronics.

Design and synthesis of a covalent organic framework bridging CdS nanoparticles and a homogeneous cobalt–bipyridine cocatalyst for a highly efficient photocatalytic CO2reduction

“…1,2 Therefore, sustained efforts have been devoted to developing sustainable energy conversion and storage alternatives, which can meet the increasing energy demand and reduce emissions into the environment. [3][4][5][6][7][8][9][10] In light of the abovementioned problems and requirements, conversion of CO 2 to carbon-based fuels, using various catalytic transformation approaches, is considered a promising strategy. [11][12][13][14] To this end, the solar-driven reduction of CO 2 has garnered signicant attention because solar energy and water are abundant and the reaction conditions are mild.…”

Metal‐Organic Frameworks and Their Derivatives‐Based Nanostructure with Different Dimensionalities for Supercapacitors

“…Reproduced with permission. [131] Copyright 2021, Wiley-VCH. b) The procedures for the synthesis of [Zn 2 (bdc) 2 dabco]n (ZBD) with different frameworks and their derived carbon.…”

“…Notably, the fabricated supercapacitor based on a flexible paper generated from the prepared nanocomposite exhibits a great potential in flexible electronics field (Figure 7a). [131] Despite the importance of downscaling MOFs to nanoscale so as to meet the urgent demand in various potential applications, the facile synthesis of nano-MOFs still remains a tough target. Schmidt and coworkers report a simple strategy to synthesize [Zn 2 (bdc) 2 dabco]n (ZBD) (bdc = benzene-1,4-dicarboxylic acid and dabco = 1,4diazabicyclo[2.2.2] octane).…”

“…a) The schematic illustration for the fabrication of MnO/Mn 7 C 3 @NGC based on the precursor of Mn-MOF. Reproduced with permission [131]. Copyright 2021, Wiley-VCH.…”

Nickel Acetate-Assisted Graphitization of Porous Activated Carbon at Low Temperature for Supercapacitors With High Performances

“…Catalytic graphitization opens a route to prepare graphitic carbon under fairly mild conditions. The conversion temperature of amorphous carbonaceous materials to graphitic carbon can be reduced to less than 800°C ( Jiang et al, 2021b ; Lam et al, 2021 ; Yang L et al, 2021 ). A variety of transition metal catalysts are commonly used, including Ni ( Yang L et al, 2021 ), Co ( Liu T et al, 2020 ), and Fe ( Semeniuk et al, 2021 ).…”