Mesoporous Thin Films: Molten Salt Assisted Self‐Assembly: Synthesis of Mesoporous LiCoO₂ and LiMn₂O₄ Thin Films and Investigation of Electrocatalytic Water Oxidation Performance of Lithium Cobaltate (Small 1/2018)

Abstract

In article number 1701913, Ferdi Karadas, Ömer Dag, and co-workers synthesize transparent mesoporous thin films of LiCoO 2 and LiMn 2 O 4 by employing a molten salt assisted self-assembly method. A clear solution of the ingredients is coated over a subtrate that is heated at elevated temperatures to obtain the transparent mesoporous metal lithiates. The mesoporous LiCoO 2 film electrode, coated over a FTO substrate, demonstrates promising water oxidation electrocatalysis at low overpotentials.

Synthesis and water oxidation electrocatalytic and electrochromic behaviours of mesoporous nickel oxide thin film electrodes

“…The slope of the peak current intensity versus scan rate plot provides information on the surface coverage of active sites. 32 The surface coverage of the electrode (m-NiO-10), calcined at 350 C decreases from 219 to 110 nm cm À2 upon annealing at 450 C. This is also consistent with the reduced surface area by high temperature treatment. Notice that the surface area also decreases from 164 to 28 m 2 g À1 and the crystallite size increases from 4.4 to 15.1 nm by annealing the electrode from 350 to 450 C, respectively.…”

“…The Tafel slope (62 mV dec À1 ) of the electrode (m-NiO-10-450) is comparable to that of cobalt and nickel-based water oxidation electrocatalysts in the literature. [32][33][34][35][36][37] The overpotentials, extracted from the Tafel equation, are 288 and 350 mV at current densities of 1 and 10 mA cm À2 , which are quite consistent with the experimental values once the IR drop is subtracted from the experimental data.…”

“…[26][27][28] However, it is difficult to retain the lm morphology using hard templating approaches; further steps and other reagents are needed to assemble them into an electrode conguration. Here, we employed the molten-salt assisted self-assembly (MASA) method [29][30][31][32] to fabricate mesoporous nickel oxide (m-NiO) as a thin lm. The MASA process involves a lyotropic liquid crystalline mesophase that is formed by molten salt and two surfactants.…”

“…The MASA process involves a lyotropic liquid crystalline mesophase that is formed by molten salt and two surfactants. [29][30][31][32] The rst step of the MASA process is obtaining a clear solution that can be coated over a substrate with a desired thickness as a lyotropic liquid crystalline gel. Calcination of the thin gel lm produces highly transparent m-NiO lm.…”

Polyvinylpyrrolidone-Induced Uniform Surface-Conductive Polymer Coating Endows Ni-Rich LiNi0.8Co0.1Mn0.1O2 with Enhanced Cyclability for Lithium-Ion Batteries

“…However, implementation of LIBs in clean electric vehicles (energy density: 300 W h kg –1 ) as well as large-scale energy storage has long been hindered by their low energy density and safety issues. − The energy density of LIBs is partly determined by the cathode materials. Up to now, numerous cathode materials have been successfully developed, such as LiCoO 2 , , LiFePO 4 , , LiMn 2 O 4 , , and layered Li­[Ni x Co y Mn 1– x – y ]­O 2 (NCM) − compounds. Among these materials, NCM, especially LiNi 0.8 Co 0.1 Mn 0.1 O 2 (NCM 811 ), has been regarded as one of the most promising cathode materials because of its high specific capacity (∼210 mA h g –1 ) as well as low cost.…”