Shape-tailorable high-energy asymmetric micro-supercapacitors based on plasma reduced and nitrogen-doped graphene oxide and MoO₂ nanoparticles

Abstract

High-energy asymmetric micro-supercapacitors have been fabricated with diversified planar geometries.

Selective deposition of metal oxide nanoflakes on graphene electrodes to obtain high-performance asymmetric micro-supercapacitors

“…1.3 F cm −3 for onion-like graphene based MSCs and 3.1 F cm −3 for laser-written graphene oxide MSCs), 62,63 and also superior to others state-of-the-art transition metal oxide based A-MSCs, e.g., MnO 2 //Fe 2 O 3 A-MSCs on Cr/Ni patterns (60 F cm −3 ), PNG-MnO 2 //PNG on a plasma reduced and nitrogendoped graphene oxide substrate (38.1 F cm −3 ), and NPG-MnO 2 //NPG-Ppy on a nano-porous gold substrate (45.3 F cm −3 ). 15,32,38 To demonstrate the device stability of our asymmetric supercapacitor, we also performed long-term cycling of Fe-Mn A-MSC by GCD at 100 μA cm −2 . Interestingly, our device retained about 95.7% of the initial value with a high coulombic efficiency (99.3%) after 10 000 cycles, as shown in Fig.…”

“…The energy density value is much higher than those of typical carbon-based micro-supercapacitors, and comparable with those of a Li thin-film battery (≤10 mW h cm −3 ) and other reported pseudocapacitive hybrid A-MSCs (Table S1 †) such as LIG-MnO 2 //LIG-FeOOH (2.4 mW h cm −3 ), MnO 2 //Fe 2 O 3 (12 mW h cm −3 ), Co(OH) 2 -EG//VN-EG (12.4 mW h cm −3 ), and PNG//PNG-MnO 2 (38.1 mW h cm −3 ) micro-supercapacitors. 15,19,30,38,64…”

“…7,8 According to the working potential windows of various transition metal oxides in aqueous electrolytes, most of the oxides are used as positive electrode materials with a stable potential range of around 0-1 V (vs. SCE), such as pseudocapacitive oxides MnO 2 , ZnO and battery-type oxides Co 3 O 4 , V 2 O 5 , SnO 2 , NiO, etc. [9][10][11][12][13][14][15] On the other hand, there are few studies reporting negative electrode materials with a working potential range below 0 V (vs. SCE), which includes Fe 2 O 3 , MoO 3 , and metal nitrides (VN), etc. [16][17][18][19] Among these oxides, MnO 2 and Fe 2 O 3 as positive and negative electrode materials, respectively, are the most promising candi-dates for ASC devices because of their high theoretical capacitance, low cost, abundance and environmental friendliness.…”

Solid Phase Exfoliation for Producing Dispersible Transition Metal Dichalcogenides Nanosheets

“…[ 34 ] In this context, all solid‐state planar MoSe 2 ‐MSC were fabricated following previous reported procedure (see experiment details). [ 35 ] In‐plane design of MoSe 2 ‐MSCs was demonstrated in Figure a and the electrodes thickness is around 100 nm (Figure S14, Supporting Information). The in‐plane design prohibits the usage of separator, which is compatible for on‐chip integration for flexible electronics compared with all solid‐state thin film battery or sandwich type supercapacitor.…”

Recent Progress in Graphene‐Based Microsupercapacitors

“…A newer PVA‐LiCl aqueous gel electrode used in the asymmetric microsupercapacitors (AMSCs) device can exhibit a working voltage of 1.4 V, 38.1 μW h cm −3 and excellent bending stability over 180°. [ 168 ]…”