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[Display omitted] • A novel nanomaterial toward (CuCo/CP) electrochemical water splitting. • Facile method for Copper-Cobalt (CuCo) supported on carbon paper (CuCo/CP) composition. • The electrochemical activation of electrode led to improvement of OER and HER kinetics. • Tafel slopes has been calculated for CoCu/CP is 97.7 mV dec−1. • CuCo/CP an emerging material for different energy applications. Electrochemical water splitting is one of the most appealing approaches to produce Hydrogen as a sustainable energy resource. The efficiency of Hydrogen evolution reaction (HER) and Oxygen evolution reaction (OER) largely depends on the activity and stability of any elctrocatalyst. Herein, we have employed a facile and reproducible electrodeposition coating method to synthesize bi-metallic Copper-Cobalt (CuCo) containing electrocatalyst supported on carbon paper (CuCo/CP) for electrochemical splitting of water in neutral medium. We have accomplished superior and improved HER and OER electrocatalytic activity, regardless of lower activity of Cu toward HER and OER. The unique structure and synergistic effect of CuCo/CP displayed better electrocatalytic activity with a low overpotential of 450 mV at 10 mA.cm−2 toward HER and just 80 mV at 10 mA.cm−2 toward Oxygen evolution reaction than other Cu containing electrocatalysts. Moreover, the durability of synthesized electrocatalyst at high applied current density ensure the stable nature of the catalyst. The present study may pave the way for the rational design of electrocatalysts for efficient Oxygen and Hydrogen production applications. [ABSTRACT FROM AUTHOR]

As one of the most efficient, low-cost, and readily available electrocatalysts for oxygen evolution reaction (OER) in alkaline environments, the nickel-iron electrocatalyst is of great significance to commercial water splitting. In this study, NiFe-layered double hydroxide loaded on nickel foam (NiFe-LDH/NF) was synthesized via a simple one-step hydrothermal method, whose OER catalytic performance could be successfully optimized by further electrochemical reconstruction. The results show that NF is an effective precursor to loading crystallized Ni(OH) 2 nanoparticles during hydrothermal synthesis, leading to the generation of high-performance NiOOH during OER reconstruction. Under the optimal Ni:Fe feeding ratio, Ni 2 Fe 1 -LDH/NF requires an ultra-low OER overpotential of 239 mV at 50 mA cm−2 and 260 mV at 100 mA cm−2, whose Tafel slope is only 64.1 mV dec−1. Impressively, Ni 2 Fe 1 -LDH/NF also achieves an ultra-low voltage of 1.44 V at 10 mA cm−2 with excellent long-term stability for overall water splitting. Unlike the previous viewpoint that only Ni species dominate surface reconstruction of NiFe-LDH, in this article the decisive influence related to Fe species on the reconstruction layers' activity and stability is confirmed by electrochemistry, Raman, and XPS analysis during reconstruction process. During OER reconstruction, the surface Ni:Fe ratios can be "self-adaptively" regulated to an appropriate region, thus the stable reconstruction layers rich in NiOOH can be formed as the protective shells for NiFe-LDH. Furthermore, such "self-adaptive" reconstruction, assisted with appropriate initial Ni:Fe feeding ratios, can also stimulate more Ni3+ active sites for OER, benefitting the outstanding catalytic performance of NiFe-LDH/NF for overall water splitting and prospective large-scale application. [Display omitted] • There are some highlights in this paper may be found interested by the general readers. • Unstable iron-rich phases start self-adaptively electrochemical reconstruction. • Self-adaptive reconstruction promotes the OER catalytic activity and stability. • The optimal electrocatalyst exhibits 260 mV overpotential at 100 mA·cm−2 for OER. • The electrocatalyst only needs 1.44 V at 10 mA·cm−2 for overall water splitting. [ABSTRACT FROM AUTHOR]

[Display omitted] • MIL-53(Fe)/metal (Ni, Co, Mn)-phenolic network nanoarchitectures were fabricated for OER. • MIL-53(Fe)/Ni-phenolic network nanoarchitectures revealed the best electrochemical performance due to interface effect. • This work supplied an efficient approach for water splitting. The interface nature of composite catalysts affected drastically the oxygen evolution reaction (OER) behavior. In this paper, nanoarchitecture consisted of Fe-based metal–organic frameworks (MIL-53) and metal-phenolic networks were created. Metal (Mn2+, Co2+, and Ni2+) phenolic networks were assembled on the surface of MIL-53 to form heterostructures. Among them, MIL-53(Fe)/Ni-phenolic network nanoarchitectures revealed the best electrochemical performance. The existence of MIL-53 enhanced the adsorption ability for OH− in the nanoarchitectures. The electron transfer between MIL-53 and Ni-phenolic networks adjusted the filling degree of e g orbitals to optimize the bonding strength between Fe3+/Ni2+ and oxygen intermediate species. MIL-53/Ni-phenolic networks nanoarchitectures exhibited well OER performance with a potential of 282 mV at 10 mA cm−2. This work provided an efficient insight into the structure-properties relation of a promising heterostructure catalyst for water splitting. [ABSTRACT FROM AUTHOR]

Hydrogen production from electrochemical water dissociation has been considered as a facile and promising approach to address energy related crisis in the world. In this regard, development of high performance, stable, and cost-effective catalysts for full water splitting is highly demanded. In this work a high performance electrocatalyst based on commercially available Tin oxide nanoparticles mixed with carbon nanotubes (CNT) is presented for electrocatalytic water splitting. The catalyst prepared through facile dropped casting method and obtained a high electrocatalytic activity for full water splitting. One of the key important parameters in water splitting is producing hydrogen/oxygen at high rate under long term stability. This is problematic because it would result in catalyst degradation and performance fallen. However, herein, the prepared electrocatalyst demonstrated a high stability of more than 10 h operation under a high applied current density of 100 mA.cm−2 for hydrogen evolution reaction. For the both hydrogen and oxygen, the prepared catalyst (SnO 2 /CNT coated on carbon paper) delivered the current density of 10 mA.cm−2 at a low overpotentials of 150 mV and 250 mV, respectively. Our observations validate the excellent capability in significantly modifying the catalytic activity of transition metal compound catalysts with carbon nanostructures. [Display omitted] • A synergetic effect of CNT and SnO 2 combination on the electrocatalytic performance was observed. • A lower overpotentials required to reach high current densities, along with high stability at high current. • CNT hybridization with SnO 2 influenced the Volmer step of HER. Also, the adsorption of oxygen and hydrogen affected. • The open structure accelerated the gas detachments during OER or HER, influencing the performance of the system. [ABSTRACT FROM AUTHOR]