TY - JOUR
T1 - Protonated nickel 2-methylimidazole framework as an advanced electrode material for high-performance hybrid supercapacitor
AU - Kale, A. M.
AU - Manikandan, R.
AU - Justin Raj, C.
AU - Dennyson Savariraj, A.
AU - Voz, C.
AU - Kim, B. C.
N1 - Publisher Copyright:
© 2021 Elsevier Ltd
PY - 2021/9
Y1 - 2021/9
N2 - Metal-organic frameworks (MOFs) with high conductivity have proven to be an exciting electrode material for energy storage devices. However, most of the MOFs exhibit a low electrical conductivity, which limits their use in supercapacitors. To overcome this issue herein, a simple acid treatment method was adopted to obtain nanoflower-like nickel 2-methylimidazole framework (Ni-MOF) to improve the electrical conductivity without disrupting its framework. The sample treated with a solution of sulfuric acid (H2SO4) at optimal pH 2 (Ni-MOF-2), exhibited improved surface texture with excellent electrochemical characteristics. The Ni-MOF-2 sample displayed a high specific capacity (Cs) of 467 C/g at 1 A/g in aqueous 6 M potassium hydroxide (KOH) electrolyte than that of other samples. This is mainly due to enhanced proton conduction in Ni-MOF-2 after acid treatment. In addition, a hybrid supercapacitor (HSC) device was fabricated using battery-type Ni-MOF-2 as a positive electrode and heteroatom-enriched activated carbon (O, N, S@AC) as a negative electrode. The fabricated HSC exhibited a maximum specific capacity (Cs) of 38 mAh/g with high specific energy (Es) 39 Wh/kg and maximum specific power (Ps) of 11,079 W/kg. Moreover, the HSC displayed excellent cyclic stability of ~87% for 10,000 continuous galvanostatic charge/discharge (GCD) cycles.
AB - Metal-organic frameworks (MOFs) with high conductivity have proven to be an exciting electrode material for energy storage devices. However, most of the MOFs exhibit a low electrical conductivity, which limits their use in supercapacitors. To overcome this issue herein, a simple acid treatment method was adopted to obtain nanoflower-like nickel 2-methylimidazole framework (Ni-MOF) to improve the electrical conductivity without disrupting its framework. The sample treated with a solution of sulfuric acid (H2SO4) at optimal pH 2 (Ni-MOF-2), exhibited improved surface texture with excellent electrochemical characteristics. The Ni-MOF-2 sample displayed a high specific capacity (Cs) of 467 C/g at 1 A/g in aqueous 6 M potassium hydroxide (KOH) electrolyte than that of other samples. This is mainly due to enhanced proton conduction in Ni-MOF-2 after acid treatment. In addition, a hybrid supercapacitor (HSC) device was fabricated using battery-type Ni-MOF-2 as a positive electrode and heteroatom-enriched activated carbon (O, N, S@AC) as a negative electrode. The fabricated HSC exhibited a maximum specific capacity (Cs) of 38 mAh/g with high specific energy (Es) 39 Wh/kg and maximum specific power (Ps) of 11,079 W/kg. Moreover, the HSC displayed excellent cyclic stability of ~87% for 10,000 continuous galvanostatic charge/discharge (GCD) cycles.
KW - Battery-type electrode
KW - Hybrid-supercapacitors device
KW - Impedance spectroscopy
KW - Nanoflower
KW - Ni-MOF
UR - http://www.scopus.com/inward/record.url?scp=85105320791&partnerID=8YFLogxK
U2 - 10.1016/j.mtener.2021.100736
DO - 10.1016/j.mtener.2021.100736
M3 - Article
AN - SCOPUS:85105320791
SN - 2468-6069
VL - 21
JO - Materials Today Energy
JF - Materials Today Energy
M1 - 100736
ER -
