Reactive and Organosoluble SnO₂ Nanoparticles by a Surfactant‐Free Non‐Hydrolytic Sol–Gel Route

Abstract

Reactive SnO2 nanoparticles have been successfully prepared by a simple non‐hydrolytic sol–gel synthesis in CH2Cl2 at 110 °C by using SnCl4 as a precursor and diisopropyl ether (iPr2O) as an oxygen donor. The SnO2 nanocrystals, with a diameter of about 4 nm, formed stable sols in organic aprotic solvents in the absence of any surfactant or coordinating agent. The lack of aggregation has been attributed to the presence of Cl and OiPr surface groups instead of OH groups. These surface groups render the nanoparticles reactive towards hydroxylated surfaces, as shown by their reaction with an oxidized silicon wafer; the nanoparticles bind uniformly across the wafer to form a monolayer.

Mechanistic Aspects in the Formation, Growth and Surface Functionalization of Metal Oxide Nanoparticles in Organic Solvents

“…Another example is the nonhydrolytic reaction of metal chloride precursors with diisopropyl ether, yielding metal oxide nanoparticles coated by chloride and isopropoxide groups. Because of the unique surface chemistry, these nanoparticles were dispersible in organic solvents such as tetrahydrofuran (THF), and they were reactive towards water, alcohol or hydroxylated surfaces …”

“…[262,[264][265][266][267] Another example is the nonhydrolytic reaction of metal chloride precursors with diisopropyl ether,y ielding metal oxide nanoparticles coated by chloride and isopropoxide groups.B ecause of the unique surfacec hemistry,t hese nano-particles were dispersible in organics olvents such as tetrahydrofuran( THF), and they were reactive towards water,a lcohol or hydroxylated surfaces. [135,136,268] If the as-synthesized nanoparticles are not dispersible, then ap ost-synthetic surface functionalization or ligand exchange is required. This strategy has the advantage that the optimum ligand for as pecific application or processing step can be selected, independento fi ts compatibility with the synthesis protocol.…”

Tin Oxide Nanoparticles and SnO2/SiO2 Hybrid Materials by Twin Polymerization Using Tin(IV) Alkoxides

“…Recently, nonaqueous solution routes for the preparation of metal oxide nanoparticles were shown to be valuable methods to control the shape, size, and crystallinity of metal oxides. [39][40][41][42] Herein, we report a novel nonaqueous route to synthesize high-surface-area tin oxide nanoparticles using so-called twin polymerization (TP). This novel strategy was developed by Spange et al for the synthesis of high-surface-area metal oxides, such as SiO 2 [43,44] and TiO 2 , [45] as well as for the preparation of metal oxide nanoparticles.…”

Ultra-large scale synthesis of high electrochemical performance SnO2 quantum dots within 5min at room temperature following a growth self-termination mechanism

“…6. Cyclic voltammograms measured at different scan rate (left) and specific capacitance obtained at different scan rate (right) for sample A, B and C. [25]. No vibration bands of organic compound can be observed in the FTIR spectra of two samples.…”