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Conformational landscapes of 2,2,3,3,3-pentafluoro-1-propanol and its hydrogen-bonded dimer were explored at the molecular level using chirped pulse Fourier transform microwave spectroscopy and ab initio calculations.

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An attractive photoanode material, WO3, has suffered from its limited visible‐light absorption and sluggish surface reaction kinetics, as well as poor stability in neutral electrolytes. Herein, a NiFe/CQD/WO3 composite photoanode was designed and fabricated, with loading of carbon quantum dots (CQDs) and electrodeposition of NiFe layered double hydroxide. The NiFe/CQD/WO3 photoanode obtained a photocurrent density of 1.43 mA cm−2 at 1.23 V vs. reversible hydrogen electrode, which is approximately three times higher than that of bare WO3. During the test period of 3 h, the stability of WO3 was improved substantially after the loading of cocatalysts. Furthermore, mechanistic insights of the favored band structure and beneficial charge‐transfer pathway elucidate the high photoelectrochemical performance of the NiFe/CQD/WO3 composite photoanode.

Biomass burning greatly influences the Earth-cloud-climate system by releasing complex mixtures of organic and inorganic species into the atmosphere. 1 During biomass burning, lignin, an organic polymer and a major component of wood, 2 undergoes pyrolysis resulting in the direct release of substituted catechols. 3 3-methylcatechol (3MC), a common substituted catechol, may be photo-oxidized or aggregates with other atmospherically relevant molecules, such as water, forming small molecular clusters or hydrates. These hydrates play an important role in the early phases of aerosol particle formation, and can provide valuable thermodynamic data for modelling. To elucidate the conformationally complex hydrate structures we analyzed rotational spectra measured with a chirped-pulse Fourier transform microwave spectrometer in the 2-6 GHz range. 4 To aid in spectral assignment, we used the Conformer-Rotamer Ensemble Sampling Tool (CREST) 5 to generate an ensemble of conformers. Two monomer conformations with their respective 13 C isotopologues were assigned, followed by the determination of substitution structures and semi-experimental effective structures. With the aid of the CREST results, transitions of several hydrates, 3MC-(H 2 O) N =1−4 , were also assigned in the experimental spectrum. For the monohydrate and dihydrate, splittings of rotational transitions into quartets were observed. These splittings are a consequence of methyl internal rotation (MIR) and the proton exchange motion of water. Only MIR splittings are present for the trihydrate, while no MIR or proton exchange splitting is present for the tetrahydrate. Non-covalent interactions 6 and natural bond orbital analyses 7 were used to visualize and quantify the intermolecular interactions within each cluster.