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Oxygen vacancy (OV)-enriched black TiO2(BTO) is a promising material for supporting well-studied noble metals in the hydrogen evolution reaction (HER). Blackening TiO2by incorporating OVs substantially changes the electronic state of BTO and enhances HER catalytic performance compared to pristine TiO2. Furthermore, the incorporation of vacancies leads to deviation from a single anatase phase on a localized scale and creates a heterojunction by promoting the occurrence of localized rutile segments. Hence, synthesizing biphasic (rutile and anatase) BTO with abundant OVs and optimized Pt-metallic clusters substantially improves the electrochemical HER kinetics, though it demands a complicated multistep synthesis. Conversely, herein, a solvent-free, single-pot green synthesis route is corroborated using a pulse laser irradiation technique to achieve the desired Ov-enriched BTO structure. Controlled irradiation of anatase TiO2with a Pt precursor under optimized parameters in an air environment creates OVs and decorates the metal oxide with Pt nanoclusters. This defect formation decreases the activation energy of BTO, favoring the anatase phase and forming a localized rutile phase, which enhances HER activity through localized heterojunctions. The combined impacts of Pt nanoclusters and OVs revealed an outstanding specimen achieving a HER overpotential of 169 mV at 10 mA/cm2and a Tafel slope of 73.3 mV/dec Importantly, long-term stability during overall water splitting was further achieved. This approach offers valuable perceptions into designing highly competent catalysts and their supporting structures for various energy-associated solicitations.

Electrochemical water splitting, driven by processed catalysts, is the most reasonable method for hydrogen production. This study demonstrates an activation phenomenon with ruthenium (Ru) nanoclusters on few-layered black phosphorus (BP), greatly enhancing the electrocatalytic hydrogen evolution reaction (HER). Efficient BP exfoliation was achieved using acoustic levitators and pulsed laser irradiation in liquids (PLIL), yielding charge-transfer Ru-nanoclusters on modulated surfaces. Various PLIL parameters were examined for the optimal BP sheet size. After ruthenization, Ru’s d-band center facilitated hydrogen adsorption via Ru–H bonding. Synergy between BP’s charge-carrier properties and Ru’s active sites boosted HER kinetics with an ultralow overpotential of 84 mV at 10 mA/cm2in KOH. Additionally, the RuO2|| RuBP-2 electrolyzer demonstrated remarkable overall water splitting performance at ∼1.60 V at 10 mA/cm2. These results highlight the pivotal role of metal nanoclusters on exfoliated BP surfaces and offer a refined strategy for high-density electrocatalysts in energy conversion.

The structural information of 3‐cyanoindole ammonia cluster, 3CI(NH3)1, in molecular beams was investigated in the gas phase. We obtained UV–UV hole‐burning spectrum (UV–UV HB) to determine the number of conformers present in the molecular beams and examine their spectral features. As a result, single conformer of 3CI(NH3)1was observed in the mass‐selected one‐color resonant two‐photon ionization (1C‐R2PI) spectroscopy. The origin band of 3CI(NH3)1in the R2PI spectrum is redshifted by 122 and 71 cm−1compared to those of the 3CI monomer and 3CI 1:1 water cluster, 3CI(H2O)1, respectively. The fully optimized geometries, relative energies, transition energies, binding energies, and electrostatic potential (ESP) of the 3CI monomer, 3CI(H2O)1, and 3CI(NH3)1clusters were calculated at the B3LYP and TD‐B3LYP methods with the 6‐311++(d,p) basis set. The observed spectra are compared with the predictions of time‐dependent density functional theory calculations. The spectroscopic probe of 3CI ammonia cluster, 3CI(NH3)1, has been investigated using mass‐selected one‐color resonant two‐photon ionization (1C‐R2PI) and UV–UV hole‐burning (UV–UV HB) spectroscopy obtained from a thermal evaporation method in the gas phase. The observed spectra are compared with the predictions of density functional theory (DFT) and time‐dependent DFT (TD‐DFT) calculations.

Herein, we report the development of a tailored cobalt catalyst system of Cp*Co(III)(LX) toward intramolecular C–H nitrene insertion of azidoformates to afford cyclic carbamates. The cobalt complexes were easy to prepare and bench-stable, thus offering a convenient reaction protocol. The catalytic reactivity was significantly improved by the electronic tuning of the bidentate LX ligands, and the observed regioselectivity was rationalized by the conformational analysis and DFT calculations of the transition states. The superior performance of the newly developed cobalt catalyst system could be broadly applied to both C(sp2)–H and C(sp3)–H carbamation reactions under mild conditions.

[Cs+(Cryptand[2.2.2])]I−(1; Cryptand[2.2.2] = C222) was characterized via single‐crystal X‐ray diffraction and was shown to crystallize in the monoclinic space group I2/c system with a= 8.9605 (2), b= 23.5073 (5), c= 11.7563 (3) Å, and β= 93.792 (2)°. Stationary and magic angle spinning (MAS) experiments under different magnetic fields allowed for the separation of the chemical shift and quadrupole coupling tensor parameters. Remarkably, MAS spectra showing pure second‐order quadrupole powder patterns at 4.23 T were observed for 133Cs nuclei with small quadrupole moments owing to the large electric field gradients (EFGs) caused by short CsO and CsN bond distances in the [Cs+(C222)] ions. Stationary NMR powder patterns with a combination of the chemical shifts and second‐order quadrupolar interactions were observed. The EFG and chemical shift tensor components calculated using the atomic coordinate files and Gaussian 09 were reasonably consistent with the experimental values. MAS 133Cs NMR spectra and crystal structure of [Cs(C222)]I

C24H18N4O4, monoclinic, P21/c(no. 14), a= 16.5930(5) Å, b= 5.7298(2) Å, c= 20.8714(6) Å, β= 99.8620(10)°, V= 1955.02(11) Å3, Z= 4, Rgt(F) = 0.0415, wRref(F2) = 0.1115, T = 193 K.

While there have been various techniques, assays, and commercial kits developed to measure reactive oxygen species (ROS) with varying degrees of success, there is a lack of innovative methods to differentiate and quantify them simultaneously. In this work, we demonstrate a 19F nuclear magnetic resonance (NMR)-based method to differentiate two important types of ROS, superoxide radical anion and singlet oxygen, and to quantify them concurrently. By taking advantage of the unique chemical reactivity of two fluorine-containing molecules, 4-fluoro-3-methylphenyl boronic acid and 4-fluoro-3-methylphenol, serving as 19F NMR probes, we are able to differentiate and quantify, for the first time, superoxide radical anion and singlet oxygen generated by photosensitizers (PSs) concurrently. The results reveal that relative amounts of superoxide radical anion and singlet oxygen generated by a PS under light illumination are oftentimes sensitive to the environment, such as the presence or absence of electron donors. This method provides a means to identify the type of mechanism by which a PS functions under a given condition. We envision that this relatively simple, yet robust, method would be beneficial to a broad range of ROS-pertinent studies, such as photodynamic therapy and photoredox reactions.