An invisible hand: Hydrogen bonding guided synthesis of ultrathin two-dimensional amorphous TiO2 nanosheets

Abstract

Ultrathin two-dimensional (2D) porous nanosheets are one of the most promising nanomaterials in various applications, whereas their synthesis is still challenging. Herein, ultrathin 2D amorphous TiO 2 (a-TiO 2 ) porous nanosheet aerogel is synthesized via a surfactant-free assembly process followed by low-temperature calcination. The co-existing O-O and -OH groups on the surface of TiO 2 precursor break the 3D spherical symmetry, and the hydrogen bonding among the TiO 2 precursors is proposed as the main driving force guiding the 2D assembly. The surfactant-free assembly endows the ultrathin a-TiO 2 porous nanosheet with improved ionic and electronic conductivity. The porous structure provides high surface area and easy electrolyte penetration, accelerating the Li ion diffusion rate of the a-TiO 2 porous nanosheet. Attributing to the above advantages, the obtained a-TiO 2 porous nanosheets are one of the best anode materials for lithium-ion batteries, which is proved by the enhanced electrochemical performance.

Niobium and Fluorine Dually Doped Titanium Oxide Nanosheet Arrays for Selective Dual-Band Electrochromic Applications

“…As capping agents (F – ions) were able to selectively adsorb onto the TiO 2 surface and reduce the surface free energy of the {001} active facets, HF may serve as a shape directing agent for the growth of (001) plane-oriented TiO 2 crystals . The production of a dense stacking architecture could be ascribed to the formation of a bonding network during the reaction, which triggered the nucleation of TiO 2 on the initially formed NSs surface. , In the Fourier transform infrared-attenuated total reflectance (FTIR-ATR) spectrum (Figure S1), the broad peak at 3150 cm –1 could be ascribed to hydrogen bonds in the nanoscale network sample. − However, this kind of densely packed NSs is unfavorable for the ion transportation in an EC process. Holding the concentration of fluorine ions constant, the effect of Nb doping on the sample morphology was investigated by varying the atomic ratio of Nb to Ti in the precursor.…”

Activating the electrode–electrolyte interface via a ZnO@black phosphorus modulation layer for dendrite-free Li metal anodes

“…The lithium metal anode has recently regained the attention of researchers due to its lowest electrochemical potential (À3.045 V vs. the standard hydrogen electrode) and high theoretical capacity (3860 mA h g À1 ), making it highly desirable for high energy density devices. [1][2][3][4][5][6] Despite its numerous advantages, the commercialization of the lithium metal anode is still hampered by severe lithium dendrite growth. [7][8][9][10] The lithium dendrites usually cause a series of critical issues in the anode, such as volume expansion and dead lithium, ultimately leading to battery failure.…”

Sand‐Fixation Model for Interface Engineering of Layered Titania and N/O‐Doped Carbon Composites to Enhance Potassium/Sodium Storage

“…[4][5][6][7][8] The barrier for widespread use is the large ionic radii of Na ion (1.02 Å) and K ion (1.38 Å), consequently making it challengeable to develop high-performance electrode materials. [9,10] Layered titania (L-TiO 2 ) is a typical layered metal oxide with high specific capacity (compared to their bulk counterparts), [11][12][13][14] moderate working voltage (≈0.6 V), and low cost. [15] The aforementioned advantages make it a promising anode for energy storage.…”

“…Layered titania (L‐TiO 2 ) is a typical layered metal oxide with high specific capacity (compared to their bulk counterparts), [ 11–14 ] moderate working voltage (≈0.6 V), and low cost. [ 15 ] The aforementioned advantages make it a promising anode for energy storage.…”