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The document is the contents list for the journal "Chemical Communications" published on September 25, 2024. It includes various articles on topics such as responsive DNA hydrogels, lithium metal-based battery systems, and strategies in photochemical alcohol oxidation. The journal is published by The Royal Society of Chemistry, a leading chemistry community, and aims to connect the world with the chemical sciences. [Extracted from the article]

Using light absorbing semiconductors to harvest solar energy has long been considered as a promising approach for driving chemical reactions. Photochemical oxidation of alcohols catalyzed by noble-metal free nanomaterials is particularly attractive due to the bio-derivable nature of the substrate and the wide availability of such catalysts. Here, a number of strategies that could facilitate the progress are discussed, where it is concluded that the photochemical alcohol oxidation process can benefit from both mechanistic optimization of the electron-transfer steps and structural engineering of the light-absorbing nanomaterials. [ABSTRACT FROM AUTHOR]

Herein, a new electrochemical sensing system based on lutetium copper nanoparticles supported on hexagonal boron nitride (Lu‐Cu@h‐BN) was designed for the sensitive detection of ciprofloxacin (CIP) antibiotic. A simple hydrothermal method was used to synthesize the nanocomposite. The structural and morphological characteristics of the as‐prepared nanocomposite were investigated using various analytical techniques such as Fourier transform infrared spectroscopy (FTIR), X‐ray diffraction (XRD), scanning electron microscopy (SEM), and X‐ray photoelectron spectroscopy (XPS). The newly developed Lu‐Cu@h‐BN nanocomposite was used as an electrode modifier for sensing and signalling of CIP. Cyclic voltammetry (CV) and electrochemical impedance spectroscopy (EIS) were used to study the electrochemical activities of the bare GCE, Cu‐h‐BN/GCE, Lu‐h‐BN/GCE, Lu‐Cu/GCE, and Lu‐Cu@h‐BN/GCE. The electro‐oxidation of CIP on electrode surface exhibited an irreversible, diffusion‐controlled process. The sensor system obtained a wider linear range of (0.05–100 μM) with a lower detection limit value of 0.03 μM and sensitivity 0.7443 μA μM−1 cm−2. Furthermore, the sensor demonstrated an excellent selectivity, good stability, and reproducibility, with acceptable recoveries of 96 % to 104 % in real water sample analysis. [ABSTRACT FROM AUTHOR]

Bismuth(III) vanadate (BiVO4) films show activity for direct benzyl alcohol (PhCH2OH) oxidation to benzaldehyde (PhCHO) in acetonitrile solvent. Introducing tetrabutylammonium nitrate (Bu4NNO3) drastically reduces the overpotential required to generate the PhCHO product while maintaining a high faradaic efficiency (FE) >90 %. BiVO4 corrosion accompanies PhCH2OH oxidation. However, the presence of nitrate ions (NO3−) results in significantly less bismuth‐ and vanadium‐ion leaching (determined by ICP‐MS analysis), as well as reduced surface roughening (determined by SEM imaging). In this reaction, it is proposed that rate‐determining NO3− oxidation generates a highly reactive nitrate radical (NO3⋅) that reacts with PhCH2OH by hydrogen‐atom abstraction (HAT). NO3− is stoichiometrically consumed by the irreversible formation of electrochemically inert HNO3, characterized by an ECi mechanism, rather than a catalytic EC′ mechanism. In the presence of PhCH2OH, NO3− oxidation on BiVO4 becomes more facile; every order of magnitude increase in PhCH2OH concentration shifts the NO3−/ NO3⋅ equilibrium potential negatively by 200 mV. The shift results from the introduction of a consumption pathway for the nitrate radical intermediate via a coupled chemical step with benzyl alcohol. This report is the first example of photoelectrochemical NO3⋅ generation to initiate indirect PhCH2OH oxidation. [ABSTRACT FROM AUTHOR]

Triclinic CuWO4 and Zn doped CuWO4 nanocomposites have been synthesized by the solid state reaction method to evaluate the Photoelectrochemical (PEC) performance of the photoelectrodes. The existence of WO3 along with CuWO4 is affirmed by the XRD, XPS spectra and HRTEM images. PEC measurements showed that the generated photocurrent is found to be maximum of about 8.94 mA/cm2 for Zn doped CuWO4whereas it is 2.63 mA/cm2 for bare CuWO4 electrode measured at 0.1 M of Na2SO4 acts as a suitable electrolyte under the illumination. The carrier density (Nd) of the nanocomposites is determined by Mott‐Schottky plot that has n‐type conductivity for both the samples. The negative flat band potential of −0.52 V for Zn doped CuWO4 might be attributed to decrease in depletion width. Zn doped CuWO4 shows higher power conversion efficiency of about 3.95%. The solution resistance and charge transfer resistance of both the photoelectrodes were calculated using Nyquist plot and it is lower for Zn‐CuWO4 which indicates better conductivity and electron transfer rate. [ABSTRACT FROM AUTHOR]

The aerobic photochemical oxidation of benzylamine was carried out on the ternary oxides CuWO4 and BiVO4 as a test proton-coupled-electron-transfer reaction in acetonitrile. Both oxides give the coupled imine product, N-benzylidenebenzylamine, in near quantitative (98–99%) yield, with rate constants of 0.34 h−1 g−1 and 0.70 h−1 g−1 for CuWO4 and BiVO4, respectively. [ABSTRACT FROM AUTHOR]

Titanium niobium oxynitrides (TiNbON) are an attractive category of potential photocatalysts, but strategies for preparing them remain limited. We adapt the wet chemical “urea glass” method for pure transition metal nitrides to single-phase mixed-metal titanium niobium nitrides for a range of niobium mole fractions. We then oxidize the nitrides by heating in air to prepare titanium niobium oxynitride that absorbs visible light of λ≤ 550 nm. The materials are characterized by powder X-ray diffraction, scanning electron microscopy, and diffuse reflectance UV-vis spectroscopy. Their photochemical activity as a function of Nb fraction is benchmarked with methylene blue photomineralization promoted by full-spectrum AM 1.5G solar irradiation with and without a λ≥ 400 nm cut-on filter. First-order Langmuir–Hinshelwood rate constants for photomineralization reveal a composition with ∼8% Nb to have superior reactivity. Full compositional analysis by Kjeldahl chemical nitrogen determination and energy-dispersive X-ray spectroscopy yields a chemical formula of Ti0.92Nb0.08O1.97N0.03. Finally, electron paramagnetic resonance spectroscopy correlates a localized Nb4+ defect with increased photochemical reaction rate. [ABSTRACT FROM AUTHOR]

Correction for ‘Improving the stability and selectivity for the oxygen-evolution reaction on semiconducting WO3 photoelectrodes with a solid-state FeOOH catalyst’ by Charles R. Lhermitte et al., J. Mater. Chem. A, 2016, DOI: 10.1039/c5ta04747a. [ABSTRACT FROM AUTHOR]

We report the optical and electrical properties of chemically-doped bilayer graphene stack by tetracyanoethylene, a strong electron acceptor. The Tetracyanoethylene doping on the bilayer graphene via charge transfer was confirmed by Raman spectroscopy and Infrared Fourier transform spectroscopy. Doped graphene shows a significant increase in the sheet carrier concentration of up to 1.520×1013 cm-2 with a concomitant reduction of the sheet resistance down to 414.1 Ω/sq. The high optical transmittance (ca. 84%) in the visible region in combination with the low sheet resistance of the Tetracyanoethylene-doped bilayer graphene stack opens up the possibility of making transparent conducting electrodes for practical applications. [ABSTRACT FROM AUTHOR]

A table of contents for the issue is presented.

WO3 electrodes were synthesized via a sol–gel route followed by the photoelectrochemical deposition of a solid state FeOOH oxygen-evolution catalyst (OEC) to observe its effects on electrode stability and selectivity towards the oxygen evolution reaction (OER). WO3 photoanodes have been reported to degrade in aqueous solutions with pH ＞ 3 due to the material's Arrhenius acidity and the potential formation of reactive peroxide intermediates on the WO3 surface during the course of photoelectrochemical water oxidation. The stability during photoelectrochemical OER of WO3 and WO3–FeOOH photoanodes was measured at 1.23 V vs. RHE at pH 4 and 7 in phosphate-buffered solutions. Additionally, the faradaic efficiencies of the electrodes for OER were measured at pH 4. WO3–FeOOH electrodes demonstrate a 95.9 ± 1.6% faradaic efficiency for OER in pH 4 potassium phosphate buffer at current densities of ∼0.75 mA cm−2 under 200 mW cm−2 AM1.5G illumination and an applied bias of 1.43 V vs. RHE. These experiments demonstrate that adding an FeOOH co-catalyst dramatically improves the stability of the electrodes, selectivity, and rate of OER versus that observed on WO3 films. [ABSTRACT FROM AUTHOR]

A table of contents for the January 14, 2016 issue of the "Journal of Materials Chemistry A" is presented.

A compilation of electrolytes within the standard RPhOMgCl and AlCl3 in a THF electrolyte system with varying alkyl-based steric bulks about the phenol ring were prepared and cycled electrochemically. Most notably, 2,4,6-trimethylphenol-based solutions exhibited high conductivity (2.56 mS cm−1) and compatibility with the Chevrel-phase Mo6S8 intercalation cathode (over 200 h cycle time at C/10 current). [ABSTRACT FROM AUTHOR]

In contrast to high spin pyridyl diimine iron(ii) dichloride complexes, analogous bis(amidinato)-N-heterocyclic carbene iron(ii) and iron(iii) complexes demonstrate complex magnetic behaviour. In the solid state, they are best described as intermediate spin complexes at low temperatures that demonstrate gradual spin transitions beginning near or below room temperature. Treating the bis(amidinato)-N-heterocyclic carbene iron(ii) complex with an aryl azide revealed enhanced reactivity compared to analogous complexes supported by pyridyl diimine ligands. [ABSTRACT FROM AUTHOR]

A table of contents for the "Journal of Materials Chemistry A" is presented.

Using Al(OPh)3 rather than the typical AlCl3 with Grignard reagents affords a Mg-ion electrolyte with a reduced chloride content. A 1 : 4 Al(OPh)3–PhMgCl mixture gives a magnesium tetraphenylaluminate salt that exhibits anodic stability up to 5 V vs. Mg2+/0 on both platinum and stainless steel working electrodes, and shows much reduced corrosion (pitting) of stainless steel after extended electrolysis at 4.5 V. [ABSTRACT FROM AUTHOR]

Directed enzyme/prodrug therapy (DEPT) has promising application for cancer therapy. However, most current DEPT strategies face shortcomings such as the loss of enzyme activity during preparation, low delivery and transduction efficiency in vivo and difficultly of monitoring. In this study, a novel magnetic directed enzyme/prodrug therapy (MDEPT) was set up by conjugating β-glucosidase (β-Glu) to aminated, starch-coated, iron oxide magnetic iron oxide nanoparticles (MNPs), abbreviated as β-Glu-MNP, using glutaraldehyde as the crosslinker. This β-Glu-MNP was then characterized in detail by size distribution, zeta potential, FTIR spectra, TEM, SQUID and magnetophoretic mobility analysis. Compared to free enzyme, the conjugated β-Glu on MNPs retained 85.54% ± 6.9% relative activity and showed much better temperature stability. The animal study results showed that β-Glu-MNP displays preferable pharmacokinetics characteristics in relation to MNPs. With an adscititious magnetic field on the surface of a tumor, a significant quantity of β-Glu-MNP was selectively delivered into a subcutaneous tumor of a glioma-bearing mouse. Remarkably, the enzyme activity of the delivered β-Glu in tumor lesions showed as high as 20:123 ± 5:022 mU g-1 tissue with 2.14 of tumor/non-tumor β-Glu activity. [ABSTRACT FROM AUTHOR]

Nanocrystals of Li4Ti5O12 (LTO) have been prepared by processing an ethanol-toluene solution of LiOEt and Ti(OiPr)4 using a carbon black template. The mechanism of crystal growth has been tracked by SEM and TEM microscopies. The resulting nanocrystals grown using the carbon template (C-LTO) show less aggregation than materials prepared from solution without the template (S-LTO), which is reflected in higher surface area (27 m2/g) and concomitantly smaller particle size (58 nm) for C-LTO compared to 20 m2/g and 201 nm for S-LTO. Electrochemically, thin-film electrodes composed of C-LTO demonstrate reversible cycling, storing ∼160 mAh/g at both 1 C (175 mA/g) and 10 C current. Important is that resistance to charge transfer between the C-LTO nanocrystals and added conducting carbon is 3 times smaller than that for S-LTO. Accordingly, C-LTO shows excellent rate capability, maintaining an energy-storage capacity >150 mAh/g even at 100 C current. These characteristics solidify C-LTO a suitable replacement for carbon as a Li-ion battery anode. [ABSTRACT FROM AUTHOR]

A series of non-Grignard Mg-electrolytes with various parasubstituents was synthesized starting from commercially-available phenols. More electron-withdrawing substituents shift the anodic stability of the electrolyte by 400 mV. The p-CF3 substituted phenol exhibits the highest stability of 2.9 V vs. Mg2+/0, and cycles reversibly with the Chevrel-phase Mo6S8 Mg-ion cathode. [ABSTRACT FROM AUTHOR]