Hierarchical CoMoS₄ flakes with rich physico-electrochemical physiognomies for electrocatalytic oxygen evolution reaction

Abstract

In order to develop ultra-efficient electrocatalysts for application in oxygen electrochemistry based energy conversion and storage devices, herein, an extremely facile synthesis procedure has been innovated to synthesize hierarchical CoMoS4...

Graphitic Carbon Nitride-Induced Multifold Enhancement in Electrochemical Charge Storage of CoS–NiCo2S4 for All-Solid-State Hybrid Supercapacitors

“…In addition, hybrid capacitors possess both capacitor-type and pseudocapacitor-type electrodes in an asymmetric arrangement, which in overall increase the deliverable energy density of the device. , Furthermore, hybrid capacitors of all-solid-state architecture possess practical advantages, i.e. , no electrolyte leakage, no electrolyte decomposition, no electrode corrosion, and easy transportability, over hybrid capacitors with liquid electrolytes. , Fundamentally, the physiognomics of electrode materials play the most vital role in extracting high power and energy density from a hybrid capacitor. , In this context, transition metal (first row) sulfides are unique positive electrode materials, because of their higher electronic conductivity and S n– mobility-induced nonstoichiometry of the intrinsic metal ions. − Fundamentally, more nonstoichiometry in the electroactive metal ions facilitates more number of redox oscillations, which results in the supplemented number of electron/charge transfer during the electrochemical process. , In this context, transition metal sulfides with multiple metals and multiphasic characteristics are advantageous over transition metal sulfides with single-metal and uniphasic characteristics, since the former facilitate added redox oscillations followed by synchronously more electron/charge transfer during the electrochemical charge storage process. ,, Among various such sulfide-based electrode materials, Ni/Co-based sulfide materials are special as they offer high theoretical capacitance due to multiple electron transfer during the electrochemical processes. Furthermore, the mixed Ni/Co-based sulfide materials possess better electrical conductivity than the mono Ni/Co-based sulfide materials due to the fundamental impurity effect, which leads to the formation of intermediate bands of the other metals and the redistribution of electrons, resulting in the lower bandgap energy of the mixed Ni/Co-based sulfide materials. , Furthermore, multiphasic Ni/Co-based sulfide materials are advantageous as they additionally possess supplementary ionic nonstoichiometry (Ni 2±δ , Co 2±δ , and Co 3±δ ), which leads to more number of redox reactions and enhanced charge storage efficiency of the corresponding electrode materials.…”

“…12−15 Fundamentally, more nonstoichiometry in the electroactive metal ions facilitates more number of redox oscillations, which results in the supplemented number of electron/charge transfer during the electrochemical process. 16,17 In this context, transition metal sulfides with multiple metals and multiphasic characteristics are advantageous over transition metal sulfides with single-metal and uniphasic characteristics, since the former facilitate added redox oscillations followed by synchronously more electron/charge transfer during the electrochemical charge storage process. 15,18,19 Among various such sulfide-based electrode materials, Ni/Co-based sulfide materials are special as they offer high theoretical capacitance due to multiple electron transfer during the electrochemical processes.…”

Hierarchical and Nanocrystallite-Assembled Ultraporous NiO/MnCo2O4 for All Solid-State Hybrid Supercapacitors with Robust Energy Efficiency and Extended Operational Durability

“…The NiO/MnCo 2 O 4 ||N-rGO ASSHSC device’s energy density ( E D , Wh kg – 1 ) and power density ( P D , W kg – 1 ) were determined using the GCD parameters i (applied current in A ), Δ t (discharging time in h), Δ V (potential window as 1.85 V), and m (mass of the active electrode materials in kg) in eqs and . ,, E D = i × normalΔ t × normalΔ V m P D = E normalD normalΔ t …”

“…h i b i t e d .A), Δt (discharging time in h), ΔV (potential window as 1.85 V), and m (mass of the active electrode materials in kg) in eqs 10 and 11 8,63,64. …”

Efficient perovskite oxide@CdS composite catalysts for hydrogen production from oilfield wastewater electrolysis

“…Some HER catalysts, such as metal oxides, 6–9 hydroxides, 10–12 phosphides 13–15 and sulfides, 16–18 have been developed to replace the expensive noble metals. 19 Among them, perovskite oxides with the typical ABO 3 structure are considered highly promising electrocatalysts, where A is generally a rare earth or alkali metal ion and B is a transition metal.…”