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The ALD-SnO2 thin films are prepared at FTO and Au(111) substrates. Their investigation is referenced, if relevant, to a model system of SnO2 cassiterite (001) single crystal. Open questions about the photoelectrochemical activity and band energetics after calcination and UV-excitation are addressed. We analyze the data from AFM, Raman, Kelvin probe, photoelectrochemistry of water oxidation and electrochemical impedance spectroscopy (flatband potentials determined from Mott–Schottky plots) in aqueous and acetonitrile media. Calcination of ALD-SnO2 causes strong enhancement of work functions, surface coarsening, and decrease of band-gap. [ABSTRACT FROM AUTHOR]

Highlights: [•] TiO2(B) and anatase were synthesized in the presence of ionic liquids. [•] The growth temperature did not exceed 95°C in any step of the synthesis. [•] The content of TiO2(B) was influenced by organic solvents. [•] The nitrogen atmosphere promoted the formation of anatase. [ABSTRACT FROM AUTHOR]

Abstract: Analysis of cyclic voltammograms of Li insertion into TiO2 (B) and anatase provides information about capacitive contributions to overall charge of Li-storage. The enhancement of 30% is found in capacitive contributions (normalized to the total stored charges) in TiO2 (B) compared to that in anatase, in spite of ca. three times smaller surface area of the former. Different charging mechanism explains facilitated Li+ insertion in TiO2 (B). The difference is caused mainly by pseudocapacitive Li-storage in the bulk TiO2 (B). Deconvolution of cyclic voltammograms also indicates different capacitive contributions of the two voltammetric peaks, S1 and S2 of TiO2 (B). These results provide novel insight into the Li-storage in TiO2 (B) and its difference from that in anatase. [Copyright &y& Elsevier]

Electrochemical and chemical (with n-butyllithium)insertion of Li into TiO2(anatase) is studied by Ramanspectroscopy and by in situ Raman spectroelectrochemistry. Four isotopologuecombinations in the system, namely 6/7LixTi16/18O2(with xbeingthe insertion coefficient), are prepared and studied. Spectral assignmentis supported by numerical simulations using DFT calculations. Thecombination of experimental and theoretical Raman frequencies withthe corresponding isotopic shifts brings new inputs for several stillopen questions about the Li-insertion into TiO2(anatase). [ABSTRACT FROM AUTHOR]

The electrochemical behavior of TiO2 anatase with a predominant (001) face (ANA001) was studied by cyclic voltammetry of Li insertion and chronoamperometry. Both voltammetric and chronoamperometric diffusion coefficients and rate constants proved the higher activity of ANA001 toward Li insertion compared to that of a reference anatase material (C240) with dominating (101) facets. The enhanced activity of the anatase (001) face for Li insertion stems from synergic contributions of a faster interfacial charge transfer at this surface and a facile Li transport within a more open structure of the anatase lattice in the direction parallel to the c-axis. Despite the larger particle size of ANAOOI, the values of integral charge capacity and Li-insertion coefficient further confirmed its improved Li-insertion properties. The results of this study further complete the analogous data published on single-crystal anatase electrodes and evidence their validity for nanocrystalline materials too. [ABSTRACT FROM AUTHOR]