Blanket-like Co(OH)2/CoOOH/Co3O4/Cu(OH)2 composites on Cu foam for hybrid supercapacitor

Construction of Core‐Shell Heterostructured Nanoarrays of Cu(OH)2@NiFe‐Layered Double Hydroxide through Facile Potentiostatic Electrodeposition for Highly Efficient Supercapacitors

“…The resulting capacitance for COH@NF-LDH/CF-3 is also higher than those materials for NiFe-LDH or Cu(OH) 2 previously reported from the related kinds of literature (Figure 4i). [53][54][55][56][57][58][59] Accordingly, we found that the area capacitance has a general tendency to increase with the increasing electrodeposition time. Because a relatively long time of electrodeposition can generate more NiFe-LDH nanosheets on Cu(OH) 2 nanorods, providing more active sites and channels for electron and ion transfer, resulting in dramatically boosted total capacitance.…”

Cobalt Nanorods as Transition Metal Electrode Materials for Asymmetric Supercapacitor Applications

“…The specific areal capacitance of the Co-NRs@Ni foam electrode is reached a high value of 7857 mF cm −2 (3142.8 F g −1 ) at a current density of 1 mA cm −2 , which is much higher than those of Co(OH) 2 -NRs@Ni foam and bare Ni foam electrodes as illustrated in Figure 6e. Furthermore, its specific capacitance is superior to those of some other reported works on cobalt oxides hydroxides such as Co 3 O 4 /Ni foil (1090 F g −1 at 10 mV s −1 ), 50 β-Co(OH) 2 /Ni foam (562 F g −1 at 2 A g −1 ), 51 Co(OH) 2 /GNS/Ni foam (693.8 F g −1 at 2 A g −1 ), 52 Co(OH) 2 /APC (1287.2 F g −1 at 2 A g −1 ), 53 α-Co(OH) 2 /Co 3 O 4 (583 F g −1 at 1 A g −1 ), 54 Co(OH) 2 /GF (1139 F g −1 at 10 A g −1 ), 55 CoOOH/Ni foam (177 F g −1 at 5 mV s −1 ), 56 β-Co(OH) 2 /Ni foam (1215 F g −1 at 5 A g −1 ), 57 Co(OH) 2 buds/Ni foam (2041 F g −1 at 3 mA cm −2 ), 58 α-Co(OH) 2 (781.1 F g −1 at 10 A g −1 ), 59 Co 3 O 4 / Carbon (645 F g −1 at 5 mV s −1 ), 60 α-Co(OH) 2 (567.1 F g −1 at 1 A g −1 ), 61 Co 3 O 4 /Co(OH) 2 (867 F g −1 at 2 A g −1 ), 62 Co/ Co(OH) 2 (1048 F g −1 at 1 A g −1 ), 63 Co 3 O 4 /Co(OH) 2 (1164 F g −1 at 1.2 A g −1 ), 64 CoO/rGO (1615.0 F g −1 at 1 A g −1 ), 65 Co(OH) 2 −Co 3 O 4 (308 F g −1 at 2 mV s −1 ), 66 CoO (352 F g −1 at 1 A g −1 ), 67 Ag/Co(OH) 2 (729 F g −1 at 0.5 A g −1 ), 68 CoO (1178 F g −1 at 1 A g −1 ), 69 Co 3 O 4 /CdO (109.4 F g −1 at 1 A g −1 ), 70 α-Co/Ni(OH) 2 @Co 3 O 4 (1000 F g −1 at 1 A g −1 ), 71 CNTs/Co(OH) 2 (1154.01 F g −1 at 20 m V s −1 ), 72 Co(OH) 2 / CoOOH/Co 3 O 4 /Cu(OH) 2 (1.94 F cm −2 at 1 mA cm −2 ), 73 and so on. With increasing the current density until 20 mA cm −2 , the specific areal capacitance of the Co-NRs@Ni foam electrode is still retaining about 87% of its initial capacitance value (6835 mF cm −2 or 2734 F g −1 ), suggesting its excellent rate capability.…”

Direct Electron Transfer Coordinated by Oxygen Vacancies Boosts Selective Nitrate Reduction to N2 on a Co–CuOx Electroactive Filter

“…4,5 In addition, an electrochemical system is easy to integrate into other technologies for water and wastewater treatment. 6 To date, a number of electrodes made of noble metals (e.g., Pd and Pt), transition metals (e.g., Cu, Ni, Co, and In), and Magneĺi phase titanium oxides 7,8 have been explored in electrocatalytic nitrate reduction, with atomic hydrogen (H*) acting as an important mediator to drive the process. 9 However, the favorable formation of an N−H bond induced by H* may facilitate the reduction of nitrate to toxic ammonia on a noble metal surface (e.g., Pd), 10 and the hydrogen evolution reaction (HER) also competes for H* and decreases the Faradaic efficiency (FE) of nitrate reduction via the Heyrovsky and Tafel processes.…”