Hydrothermal synthesis and tuning of size and morphology of α-Co(OH) 2 and α-Co 2 (OH) 3 Cl nanostructures as precursors for nanosized Co 3 O 4

Electrochemical Oxidation of Chlorine-Doped Co(OH)2 Nanosheet Arrays on Carbon Cloth as a Bifunctional Oxygen Electrode

“…In recent decades, under the decline of fossil fuels and the increasing environmental issues, it is urgent to develop a renewable, clean, and sustainable energy source to ensure the rapid and healthy development of the economy. − As a result, clean storage/conversion systems such as metal–air batteries, water-splitting, and fuel cells have been significantly enhanced. The oxygen reduction reaction (ORR) and the oxygen evolution reaction (OER) occupy a significance position in the complex redox reactions of these energy conversion/storage systems, especially metal–air batteries. − However, due to the kinetically sluggish ORR and OER, it is highly necessary to develop an effective bifunctional catalyst to promote the reaction processes and enhance the catalytic stability. − Till date, although noble-metal-based catalysts have aroused much interest as a result of their high catalytic activity, they do not possess bifunctional catalytic characteristics and have limited natural resources and high prices. − Therefore, it is urgent to exploit earth-abundant and highly efficient bifunctional catalysts.Transition-metal catalysts have recently drawn great attention, thanks to their earth-abundant nature, cost-effectiveness, and environment friendliness. , Among them, a large number of studies have shown that cobalt-based materials have considerable catalytic properties, electrochemical stability, and reversibility for both ORR and OER, , including their hydroxide, oxides, and nitrides . Co-based catalyst can effectively accelerate the kinetics of oxygen catalytic reaction and promote the process of complex redox reaction in alkaline electrolytes.…”

Hierarchitecture Co 2 (OH) 3 Cl@FeCo 2 O 4 composite as a novel and high‐performance electrode material applied in supercapacitor

“…), hydrothermal route has the advantages in various product morphologies with simply, safe and low‐cost operation. However, not only Co 2 (OH) 3 Cl but also FeCo 2 O 4 need two steps to obtain in a traditional hydrothermal route . In this strategy, the precursor of the sample has been obtained after hydrothermal reaction and the final product will be prepared after the following thermal treatment.…”

“…[8][9][10] Although they have different energy storage mechanisms, the electrode material is still key point to enhance performance of supercapacitors. [11][12][13][14][15] Higher capacity and more electroactive sites are focal points in the developments of electrode materials. Among electrode materials, transition metal oxides (TMOs) show the higher performance ascribed to their complex valence states, while carbon materials usually shows a lower performance.…”

“…However, not only Co 2 (OH) 3 Cl but also FeCo 2 O 4 need two steps to obtain in a traditional hydrothermal route. 11,55 In this strategy, the precursor of the sample has been obtained after hydrothermal reaction and the final product will be prepared after the following thermal treatment. Obviously, one-step hydrothermal route can reduce the cost of the traditional hydrothermal route by discarding thermal treatment.…”

“…To research the supercapacitors clearly, the supercapacitors have been classified into two main types, the electric double layer capacitors (EDLC) and the pseudocapacitors, being sorted by their different energy storage mechanisms . Although they have different energy storage mechanisms, the electrode material is still key point to enhance performance of supercapacitors . Higher capacity and more electroactive sites are focal points in the developments of electrode materials.…”