Hetero-nanostructured Films of Titanium and Manganese Oxide Nanosheets:  Photoinduced Charge Transfer and Electrochemical Properties

Abstract

Layer-by-Layer Assembly of Multilayer Films Composed of Each Nanosheet: Ti 0.91 O 2 and MnO 2 . The deposition of one layer of Ti 0.91 O 2 nanosheets enhanced the absorbance at 255 nm by 0.139 ± 0.021, and no intrinsic absorption was observed at 372 nm. In contrast, the deposition of one layer of MnO 2 nanosheets provided the absorbance gain at 372 nm by 0.082 ± 0.014 as well as at 255 nm by 0.062 ± 0.007.

Recent development in 2D materials beyond graphene

“…Similarly, A-sites of La 0.95 Nb 2 O 7 nanosheet modified with Eu 3+ reduce the dielectric constant, leakage current density and permittivity of nanostructured film prepared by the LB deposition method [563]. Cyclic voltammetry analysis of hetero-nanostructure film of Ti 0.91 O 2 and redox MnO 2 nanosheets shows oxidation and reduction of Mn 3+ and Mn 4+ at -.15 and 05.2V respectively, which is ascribed to the movement of Li + ions in the interlayer galleries of MnO 2 nanosheets [570]. Reduction of MnO 2 sheets occurs due to the generation of photoelectron from Ti 0.91 O 2 nanosheets, which again oxidize from electrochemical methods.…”

Vertical 2D Heterostructures

“…The low-temperature design of artificial and metastable solids that are inaccessible by thermodynamically driven, high-temperature solid-state synthesis was christened molecular beaker epitaxy by Mallouk and colleagues (51) in the 1990s, implying that it can be viewed as the solution-based counterpart of gas-phase MBE. Sasaki and others extended this methodology to all-inorganic heterostructures by combining oxidic anionic and cationic nanosheets by electrostatically driven self-assembly (54)(55)(56)(57)(58).…”

“…Although the LbL process allows for a high level of control regarding the strictly alternating placement of nanosheets on a substrate, the in situ monitoring of the assembly process and the atomically resolved analysis of the obtained multilayer structures are key requirements. Monitoring the UV-vis absorbance after each deposition step has proven to be a powerful tool to study the stepwise adsorption of nanosheets with characteristic optical signatures (55,64). Likewise, spectroscopic ellipsometry (51,71,72) and quartz crystal microbalance techniques sensitively probe monolayer adsorption, albeit with less chemical specificity.…”

Effect of cation arrangement on the electronic structures of the perovskite solid solutions <span class="aps-inline-formula"><math xmlns="http://www.w3.org/1998/Math/MathML"><msub><mrow><mo>(</mo><mi>SrTiO</mi></mrow><mn>3</mn></msub><mo>)</mo><msub><mrow></mrow><mrow><mn>1</mn><mo>−</mo><mi>x</mi></mrow></msub><msub><mrow><mo>(</mo

“…Apart from epitaxial thin-film growth techniques, low-temperature soft chemistry routes are also capable of preparing nonthermodynamically stable (metastable) phases that are not accessible by conventional solid state reactions. For example, various oxide nanosheets with atomic thickness have been synthesized, and they can be arbitrarily stacked to form superlatticelike structures [45,46]. In addition, very recently a perovskite compound Ca 2 FeMnO 6 with [100] layered ordering was successfully synthesized by low-temperature oxidation from brownmillerite Ca 2 FeMnO 5 , which is inherently layered [47].…”