Flexible Electronic Systems via Electrohydrodynamic Jet Printing: A MnSe@rGO Cathode for Aqueous Zinc-Ion Batteries

Abstract

Aqueous zinc-ion batteries (ZIBs) are promising candidates to power flexible integrated functional systems because they are safe and environmentally friendly. Among the numerous cathode materials proposed, Mn-based compounds, particularly MnO 2 , have attracted special attention because of their high energy density, nontoxicity, and low cost. However, the cathode materials reported so far are characterized by sluggish Zn 2+ storage kinetics and moderate stabilities. Herein, a ZIB cathode based on reduced graphene oxide (rGO)-coated MnSe nanoparticles (MnSe@rGO) is proposed. After MnSe was activated to α-MnO 2 , the ZIB exhibits a specific capacity of up to 290 mAh g −1 . The mechanism underlying the improvement in the electrochemical performance of the MnSe@rGO based electrode is investigated using a series of electrochemical tests and first-principles calculations. Additionally, in situ Raman spectroscopy is used to track the phase transition of the MnSe@rGO cathodes during the initial activation, proving the structural evolution from the LO to MO 6 mode. Because of the high mechanical stability of MnSe@rGO, flexible miniaturized energy storage devices can be successfully printed using a high-precision electrohydrodynamic (EHD) jet printer and integrated with a touch-controlled light-emitting diode array system, demonstrating the application of flexible EHD jet-printed microbatteries.

Fabrication of amorphous Co/Mo–MnSex electrode materials for high-performance hybrid supercapacitors

“…The satellite peak of MnSe is located at 646.65 eV. 45 Fig. 4h shows the fine spectrum of Se 3d, with the peaks at 55.6 and 54.7 eV corresponding to 3d 3/2 and 3d 5/2 of Se 2− , respectively, and the peak at 59.0 eV corresponding to SeO x .…”

“…43,44 The LO mode of MnSe presents a peak at 252 cm À1 . 45 Ion doping and the final amorphous structure can provide additional active sites in the electrode material. 39,40,46,47 The samples were further analyzed by using infrared spectroscopy (Fig.…”

Boosting Manganese Selenide Anode for Superior Sodium-Ion Storage via Triggering α → β Phase Transition

“…Rietveld refinement XRD patterns of α–α-MnSe (Figure a) and δ−α-MnSe (Figure b) can be indexed as cubic α-MnSe structure with the space group of Fm 3̅ m , , and the detailed refinement results are shown in Tables S1 and S2, illustrating that both α-MnSe materials possess close lattice parameters. Raman spectra in Figure c display the characteristic peak of α-MnSe at 645.7 cm –1 , and two weak peaks located at 1345.8 and 1555.0 cm –1 are assigned to sp 3 hybrid disordered carbon (D-band) and sp 2 hybrid graphite carbon (G-band). , In order to elucidate the detailed difference between α–α-MnSe and δ−α-MnSe, electron paramagnetic resonance (EPR) was conducted as shown in Figure d, suggesting that α–α-MnSe exhibits much higher content of Se vacancies than δ−α-MnSe. , N 2 adsorption–desorption isotherms in Figure S5 reveal type-IV curves with H3 hysteresis loops, which manifests that the porous structure of both α-MnSe materials is composed of interstices between nanorods.…”

High-rate and long-life flexible aqueous rechargeable zinc-ion battery enabled by hierarchical core–shell heterostructures

“…At a current density of 0.2 A g −1 , it can be clearly seen that the coulombic efficiency (CE) of TiO 2 @MnO 2 NWAs/CC is lower than that of TiN@MnO 2 NWAs/CC, suggesting that the Zn 2+ reaction kinetics in TiO 2 @MnO 2 NWAs/CC is slow, and the existence of irreversible reactions results in a low CE, which is unfavorable for the cycling of the electrode. 5,[55][56][57][58] For long-term cycle life, TiN@MnO 2 NWAs/CC maintains outstanding cycling performance at an ultrahigh current density of 2.0 A g −1 , where the initial capacity is 186.3 mA h g −1 and then the capacity increases continuously during cycling, reaching 236.1 mA h g −1 at the 2000th cycle and returning to 189.4 mA h g −1 at the 2300th cycle, where the capacity retention is 101.6%. In contrast, the capacity of TiO 2 @MnO 2 NWAs/CC decayed continuously aer the 1000th cycle, and the capacity retention rates of TiO 2 @MnO 2 NWAs/CC and MnO 2 NSs/CC were only 14.0% and 11.9% aer 2300 cycles, respectively (Fig.…”

“…In recent years, aqueous rechargeable batteries possessing high safety and ionic conductivity have been receiving increasing attention as a promising solution to these problems. 5,6 Aqueous rechargeable zinc-ion batteries (ZIBs) offer a research direction for energy-storage systems due to the use of mild aqueous electrolytes and natural resource-abundant zinc metal anodes. [7][8][9] More importantly, as an important part of ZIBs, Zn metal anodes have many advantages such as high theoretical capacity (820 mA h g −1 , 5855 mA h cm −3 ), 10 low redox potential (−0.76 V vs. standard hydrogen electrode), 11,12 low cost, and so on.…”