A foldable, extra lightweight, flexible electrode: Chopped carbon fiber paper for growth of three-dimensional copper(II) hydroxide nanorod arrays

Fabrication of Porous Reduced Graphene Oxide Encapsulated Cu(OH)2 Core–shell Structured Carbon Fiber-Based Electrodes for High-Performance Flexible Supercapacitors

“…Three crystal peaks located 43.4°(111), 50.5°(200), and 74.3°(220) were attributed to Cu (according to JCPDS No.70−3039). 25 After alkaline-assisted oxidation, there are some typical diffraction peaks of Cu(OH) 2 in the XRD pattern, which match well with JCPDS Card No.80−0656; besides, the characteristic diffraction peaks of Cu can also be found in Cu(OH) 2 /CF, demonstrating the existence of residual Cu. This reasonably implies that the well-designed substrate could possess a enhanced conductivity to provide a fast pathway for electron transportation.…”

“…Figure h provides the XRD spectra of the Cu/CF and Cu­(OH) 2 /CF samples. Three crystal peaks located 43.4°(111), 50.5°(200), and 74.3°(220) were attributed to Cu (according to JCPDS No.70–3039) . After alkaline-assisted oxidation, there are some typical diffraction peaks of Cu­(OH) 2 in the XRD pattern, which match well with JCPDS Card No.80–0656; besides, the characteristic diffraction peaks of Cu can also be found in Cu­(OH) 2 /CF, demonstrating the existence of residual Cu.…”

“…Particularly, Cu­(OH) 2 , due to its abundant resources, chemical stability, morphology diversity, and simple preparation methods, has an excellent prospect for scalable application. , Chen et al employed a two-step method to prepare a three-dimensional (3D) Cu­(OH) 2 nanowire Cu/CF electrode material . Long et al reported a foldable and flexible electrode by the growth of 3D Cu­(OH) 2 nanorods on CF paper . However, traditional Cu­(OH) 2 was suffering from shortcomings such as irreversible capacity loss, volume expansion, and undesirable rate performance, leading to inefficient materials usage .…”

“…24 Long et al reported a foldable and flexible electrode by the growth of 3D Cu(OH) 2 nanorods on CF paper. 25 However, traditional Cu(OH) 2 was suffering from shortcomings such as irreversible capacity loss, volume expansion, and undesirable rate performance, leading to inefficient materials usage. 26 Moreover, for decorating Cu(OH) 2 on CF, it is still challenging to fabricate high-performance flexible supercapacitors in a lack of fast ion/ electron transport and diffusion path.…”

Fabrication of Multi‐Layered Paper‐Based Supercapacitor Anode by Growing Cu(OH)2 Nanorods on Oxygen Functional Groups‐Rich Sponge‐Like Carbon Fibers

“…The relationship between them was illustrated in the Ragone plots (Figure 6i). It was observed that a maximum energy density of 0.21 Wh cm −2 at a power density of 1.50 mW cm −2 can be achieved, which surpasses the performance of other reported copper/carbon paper‐based supercapacitor devices, for example, Cu(OH) 2 @CFP//AC@CFP (0.07 Wh cm −2 at 1.60 mW cm −2 ), [ 22 ] Cu(OH) 2 /Cu/Dacron//CNF/Dacron (0.036 Wh cm −2 at 0.6 mW cm −2 ), [ 45 ] Cu(OH) 2 @FeOOH/Cu (0.018 Wh cm −2 at 0.15 mW cm −2 ), [ 47 ] Cu(OH) 2 /CPCC//AC/CC (0.049 Wh cm −2 at 0.6 mW cm −2 ), [ 24 ] CuO/Co(OH)2/rGO//AC (0.033 Wh cm −2 at 4.62 mW cm −2 ), [ 48 ] Ni(OH)2@CuO@Cu//N‐rGO/NF(0.130 Wh cm −2 at 1.6 mW cm −2 ), [ 49 ] and Cu(OH) 2 @NiC2O4//AC (0.00097 Wh cm −2 at 2.4 mW cm −2 ). [ 42 ]…”