Sulfonated reduced graphene oxide encapsulated perovskite-type ErCoFe oxide nanoparticles for efficient electrochemical water oxidation.

Perovskite oxides play a vital role as electrocatalysts in water oxidation due to their flexible and unique electronic structures. In this work, Er-based perovskites ErCoFeO ( = 0.0, 0.

An enzyme-free sensor based on La-doped CoFe-layered double hydroxide decorated on reduced graphene oxide for sensitive electrochemical detection of urea.

The successful synthesis of La-doped CoFe LDH@rGO nanocomposite is reported combining the advantages of LDH and rGO and shows promising performances in electrochemical sensors. The structure of the obtained nanocomposite was investigated using Fourier transform infrared spectroscopy (FTIR), X-ray diffraction pattern (XRD), and field emission scanning electron microscope images (FE-SEM). Then, it was directly utilized to construct a carbon paste electrode (CPE) for urea detection.

CeO/CuO/NiO hybrid nanostructures loaded on N-doped reduced graphene oxide nanosheets as an efficient electrocatalyst for water oxidation and non-enzymatic glucose detection.

In this work, the three-component heterostructure of CeO/CuO/NiO was synthesized by a co-precipitation procedure and heating at a temperature of 750 °C. Then, CeO/CuO/NiO nanoparticles were successfully supported on N-doped reduced graphene oxide (N-rGO) by a hydrothermal method. The obtained nanomaterials were used as effective electrocatalysts for the oxygen evolution reaction and glucose sensing in an alkaline medium.

A new hexanuclear Fe(III) nanocluster: synthesis, structure, magnetic properties, and efficient activity as a precatalyst in water oxidation.

The oxo-bridged hexanuclear iron cluster formulated [FeIII6(μ-O)(edteH)(piv)(SCN)]·2MeCN·2HO (1) (where edteH = ,,','-tetrakis(2-hydroxyethyl)ethylenediamine; piv = pivalic acid) has been synthesized by the reaction of FeCl·4HO with edteH and piv in the presence of KSCN in CHCl/MeCN. The single crystal X-ray measurements indicated that the cluster is centrosymmetric in structure. The magnetic study demonstrated the presence of very strong antiferromagnetic coupling between the iron centers and the Brillouin fitting showed the best fit with = 5/2 and = 1.

Water oxidation reaction in the presence of a dinuclear Mn(II)-semicarbohydrazone coordination compound.

Water splitting, producing of oxygen, and hydrogen molecules, is an essential reaction for clean energy resources and is one of the challenging reactions for artificial photosynthesis. The MnCa cluster in photosystem II (PS-II) is responsible for water oxidation in natural photosynthesis. Due to this, water oxidation reaction by Mn coordination compounds is vital for mimicking the active core of the oxygen-evolving complex in PS-II.

Investigation of electrocatalytic activity of a new mononuclear Mn(II) complex for water oxidation in alkaline media.

Water splitting is a promising way to alleviate the energy crisis. In nature, water oxidation is done by a tetranuclear manganese cluster in photosystem II. Therefore, the study of water oxidation by Mn complexes is attractive in water splitting systems.

Electrocatalytic water oxidation by a Ni(ii) salophen-type complex.

A new mononuclear Ni(ii) complex, NiL (1), was synthesized from the reaction of Ni(OAc)·4HO and salophen-type NO-donor ligand, HL (where HL = 2,2'-((1,1')-((4-chloro-5-methyl-1,2-phenylene)bis(azanylylidene))bis(methanylylidene))diphenol), in ethanol. The obtained complex was characterized by elemental analysis, spectroscopic techniques and single crystal X-ray analysis. The complex was studied as a water oxidizing catalyst and its electrocatalytic activity in the water oxidation reaction was tested in 0.

Optical Response of Two Azo Ligands Containing Salicyaldimine-based Ligand as Side Chains Towards Some Divalent Metal Ions and Their Antioxidant Behavior.

According to applicability of azo-azomethine compounds in chemical sensors and biological activities, two receptors: 1,2-[1-(3-imino-4-hydroxophenylazobenzene)]-4-nitrobenzene (1) and 1,2-[1-(3-imino-4-hydroxophenylazo-4-nitrobenzene)]-4-nitrobenzene (2) are investigated for detection of nickel, cobalt, copper, lead, mercury, zinc and cadmium divalent metal ions by UV-vis spectroscopy. With the addition of all metal ions to the DMSO solution of ligands, the peaks at 558 and 549 nm increase in intensity with hypsochromic or bathochromic shifts except Zn2+ ions and 2, while the peaks at 388 and 391 nm dramatically decrease in intensity. In both cases, the largest shift is observed after addition of copper ions.

Spectroscopic properties of some new azo-azomethine ligands in the presence of Cu(2+), Pb(2+), Hg(2+), Co(2+), Ni(2+), Cd(2+) and Zn(2+) and their antioxidant activity.

Due to their potential applicability as selective receptors in optical sensors, two novel azo Schiff-base derivatives I and II are synthesized and characterized with FT-IR, (1)H NMR and elemental analysis techniques. The optical response of azo groups of I and II towards Ni(2+), Co(2+), Cu(2+), Pb(2+), Hg(2+), Zn(2+) and Cd(2+) metal ions is studied in DMSO by UV-vis spectroscopy. The absorption spectra of both compounds with cations show marked changes.

Optical spectroscopy studies of the complexation of bis(azophenol)calix[4]arene possessing chromogenic donors with Ni2+, Co2+, Cu2+, Pb2+ and Hg2+.

Due to their potential applicability as selective receptors in electrochemical or optical sensors, a bis(azophenol)calix[4]arene derivative H(2)L has been investigated. The complexation properties of this molecule towards Ni(2+) and Co(2+) metal ions has been studied. It is revealed that this ligand exhibits tetradentate with N(2)O(2) core when bound to Ni (II) or Co (II) metal ion.