TY - JOUR
T1 - Synchronously manipulating Zn2+ transfer and hydrogen/oxygen evolution kinetics in MXene host electrodes toward symmetric Zn-ions micro-supercapacitor with enhanced areal energy density
AU - Cao, Zhiqian
AU - Fu, Jimin
AU - Wu, Mingzai
AU - Hua, Tao
AU - Hu, Haibo
N1 - Funding Information:
This work was financed by National Natural Science Foundation of China (51871001 and U2003132), the University Synergy Innovation Program of Anhui Province (GXXT-2019–016), Outstanding Youth Fund of Anhui Province (1808085J10), and Open fund for Discipline Construction, Institute of Physical Science and Information Technology, Anhui University (S01003102).
Publisher Copyright:
© 2021 Elsevier B.V.
PY - 2021/9
Y1 - 2021/9
N2 - Sluggish divalent charges (e.g., Zn2+) diffusion within MXene host electrodes due to the larger sizes and stronger coulomb interactions compared to those of dominant univalent charges is an essential issue in developing MXene-based microsupercapacitors (MSCs) of higher theoretical energy densities. Herein, MXene/bacterial cellulose fiber (BCF) hybrid films with effectively expanded interlayer spacing between re-stacked few-layered MXene sheets via homogeneous intercalation of BCF nanospacer were designed and prepared. The electrochemical testing and molecular dynamics simulation demonstrated the consequently widened ions-transport-channels between few-layered MXene sheets can effectively reduce the diffusion barrier of Zn2+ within the MXene/BCF host electrodes compared to pure MXene film electrodes without BCF nanospacer. Further in-situ Raman and ex-situ XPS spectroscopy characterizations suggest: the consequently accelerated Zn2+ diffusion involved adsorption/desorption featured charge storage, and followed electrochemical reaction of Zn2+ with oxygen terminal groups on the MXene flakes induced additional pseudocapacitance within the MXene/BCF host electrodes simultaneously contribute to the acquired superior areal capacitance of the fabricated symmetrical aqueous Zn-ions MSCs (ZMSCs) based on the MXene/BCF host electrodes and Zn(CF3SO3)2/polyacrylamide hydrogel electrolyte. Meanwhile, combined with doubled voltage window (1.2 V) benefiting from the cocurrently suppressed kinetics of hydrogen/oxygen evolution within the MXene/BCF host electrodes, a tremendously increased areal energy density (34.0 μWh cm−2) in comparison with that employing conventional H2SO4/polyacrylamide hydrogel electrolyte (0.6 V/8.6 μWh cm−2) is finally realized. The work demonstrates a simple and effective strategy to synchronously boost bivalent Zn2+ diffusion and depress hydrogen/oxygen evolution within MXene host electrodes toward symmetric ZMSCs of high areal energy density.
AB - Sluggish divalent charges (e.g., Zn2+) diffusion within MXene host electrodes due to the larger sizes and stronger coulomb interactions compared to those of dominant univalent charges is an essential issue in developing MXene-based microsupercapacitors (MSCs) of higher theoretical energy densities. Herein, MXene/bacterial cellulose fiber (BCF) hybrid films with effectively expanded interlayer spacing between re-stacked few-layered MXene sheets via homogeneous intercalation of BCF nanospacer were designed and prepared. The electrochemical testing and molecular dynamics simulation demonstrated the consequently widened ions-transport-channels between few-layered MXene sheets can effectively reduce the diffusion barrier of Zn2+ within the MXene/BCF host electrodes compared to pure MXene film electrodes without BCF nanospacer. Further in-situ Raman and ex-situ XPS spectroscopy characterizations suggest: the consequently accelerated Zn2+ diffusion involved adsorption/desorption featured charge storage, and followed electrochemical reaction of Zn2+ with oxygen terminal groups on the MXene flakes induced additional pseudocapacitance within the MXene/BCF host electrodes simultaneously contribute to the acquired superior areal capacitance of the fabricated symmetrical aqueous Zn-ions MSCs (ZMSCs) based on the MXene/BCF host electrodes and Zn(CF3SO3)2/polyacrylamide hydrogel electrolyte. Meanwhile, combined with doubled voltage window (1.2 V) benefiting from the cocurrently suppressed kinetics of hydrogen/oxygen evolution within the MXene/BCF host electrodes, a tremendously increased areal energy density (34.0 μWh cm−2) in comparison with that employing conventional H2SO4/polyacrylamide hydrogel electrolyte (0.6 V/8.6 μWh cm−2) is finally realized. The work demonstrates a simple and effective strategy to synchronously boost bivalent Zn2+ diffusion and depress hydrogen/oxygen evolution within MXene host electrodes toward symmetric ZMSCs of high areal energy density.
KW - Hydrogen/oxygen evolution kinetics
KW - Molecular dynamics
KW - MXene
KW - Zn-ions micro-supercapacitors
KW - Zn transfer kinetics
UR - http://www.scopus.com/inward/record.url?scp=85105808960&partnerID=8YFLogxK
U2 - 10.1016/j.ensm.2021.04.047
DO - 10.1016/j.ensm.2021.04.047
M3 - Journal article
AN - SCOPUS:85105808960
SN - 2405-8297
VL - 40
SP - 10
EP - 21
JO - Energy Storage Materials
JF - Energy Storage Materials
ER -