Facile Synthesis of Ultrathin Lepidocrocite Nanosheets from Layered Precursors

Abstract

Ultrathin two-dimensional nanosheets have been widely studied because of their peculiar properties and promising applications. As a typical layered material, successful exfoliation of freestanding ultrathin lepidocrocite (γ-FeOOH) nanosheets from the bulk material has not been reported to date. Herein, we report a facile synthetic route to prepare ultrathin lepidocrocite nanosheets with a thickness of approximately 2-3 nm from FeOx -propanediol layered precursors through weakening of the hydrogen bonds during the crystallization process. The ultrathin morphology and single-crystal structure of the nanosheets were confirmed by transmission electron microscopy, X-ray diffraction, and atomic force microscopy. The formation process of these nanosheets demonstrated simultaneous exfoliation and crystallization of lepidocrocite in basic aqueous solution. The obtained ultrathin nanosheets exhibited a much lower Néel temperature (18.3 K) than bulk lepidocrocite and weak ferromagnetic behavior below this temperature.

Self-powered H2 production with bifunctional hydrazine as sole consumable

“…The 129 mV value is also among the best reported for HzOR (Supplementary Table 3 ). Meantime, pure FeS 2 nanosheets were synthesized through a hydrolysis reaction 31 and a sulfurization process (see details in Methods and Supplementary Fig. 18 ).…”

“…For comparison, pure FeS 2 nanosheets (Supplementary Fig. 18 ) were synthesized by directly pyrolyzing ϒ -FeOOH nanosheets with sulfur powder under Ar at 300 °C for 2 h. The ϒ -FeOOH nanosheets were synthesized by a hydrolysis process: 31 Specifically, NH 4 HCO 3 (1.50 g) and FeCl 3 (0.27 g) were first added to 30 mL propanediol. After 30-min stirring, a homogeneous solution was attained, and it was placed into a Teflon-lined stainless steel autoclave (50 mL).…”

Structure of single sheet iron oxides produced from surfactant interlayered green rusts

“…Thus, thin goethite particles (6.8 nm thickness corresponding to [110] plane) has been synthesized as part of a goethite/graphene oxide composite 79 . Similarly, 2D ultrathin feroxyhite (1.1 nm thick) 83 and 2D lepidocrocite 82 ( 2~3 nm thick) has been synthesized. All of these nano-sized iron oxides show up their typical powder XRD traces demonstrating the presence of coherent scattering domains consisting of at least several atomic layers.…”

Bottom-up Approach Design, Band Structure, and Lithium Storage Properties of Atomically Thin γ-FeOOH Nanosheets

“…Previous work of ultrathin lepidocrocite FeOOH has been reported by a hydrolysis route, but the yield rate of the product is too low to realize electrochemical application. The high-yield synthesis of atomically thin FeOOH nanosheets remains a challenge up to date . The main reason for the low yield rate of reported FeOOH sheets is the strong chemical bonds between the layers of FeOOH which are hard to break using a facile method …”

“…The high-yield synthesis of atomically thin FeOOH nanosheets remains a challenge up to date. 19 The main reason for the low yield rate of reported FeOOH sheets is the strong chemical bonds between the layers of FeOOH which are hard to break using a facile method. 20 Herein, we develop an alternative method with a high yield rate, namely a bottom-up approach, to produce atomic γ-FeOOH nanosheets with a thickness of ∼1.5 nm.…”