Jem 2010f electron microscope

The particle yield Y was defined as follows. where W_collect is the weight of final products after washing and drying and W_theory is the maximum particle weight of Fe₂O₃ when the reaction is complete. X-ray diffraction patterns of the products were obtained via X-ray diffraction (XRD) (MiniFlex600-C; Rigaku Corp.) using Cu Kα radiation. The crystallite size was evaluated using the Scherrer equation, where 0.90 of shape factor was used. The products were observed by transmission electron microscopy (TEM) (H-7650; Hitachi Corp.) operated at 100 kV. High resolution TEM (HR-TEM) images and electron diffraction pattern of particle colony were acquired using a JEOL JEM-2010F electron microscope operated at 200 kV. The solid products for TEM and HR-TEM analysis were dispersed in cyclohexane before transferred onto the copper grids with a organic membrane. The mean size, with their standard deviation, of the particles was determined by observing approximately 200 particles for TEM analysis. Thermogravimetric analysis was performed from room temperature to 600 °C at a ramp rate of 10 °C min⁻¹ and at N₂ atmosphere using a thermogravimetric analyzer (TGA) (TGA-50; Shimadzu Corp.). The absorbed state of an organic surfactant on the iron oxide surface was investigated using a Fourier transform infrared spectrometer (FT-IR) (FT-IR4100; JASCO Co., Ltd.).

Transmission electron microscopy (TEM), high-resolution TEM (HRTEM), and scanning TEM (STEM) were performed on a JEOL JEM-2010F electron microscope operated at 200 kV with the supplied software for automated electron tomography. For the TEM measurements, a drop of the nanoparticle solution was dispensed onto a 3 mm carbon-coated copper grid, and excessive solution was removed by an absorbent paper. Then the sample was dried under vacuum at room temperature. An energy dispersive X-ray spectroscopy (EDX) analyzer attached to the TEM operated in the STEM mode was used to analyze the chemical compositions of the synthesized nanoparticles. UV-visible spectra of Ag, core-shell Pt@Ag, core-shell-shell Pt@Ag@Ag-Pd and CBS Pt-Pd colloidal solutions in toluene were collected on a Hitachi U-3900 spectrophotometer. Powder X-ray diffraction (XRD) patterns were recorded on a Bruker D8 diffractometer, using Cu Kα radiation (λ = 0.154056 nm). The content of Ag in core-shell-shell Pt@Pd@Ag-Pd nanoparticles after NaCl treatment was determined using inductively coupled plasma-optical emission spectrometry (ICP-OES) technique on a Perkin Elmer 6300 spectrograph.

The UV-Visible spectra were recorded on a Nanodrop 2000c spectrophotometer (Thermo Scientific, WA, USA). The photoluminescence (PL) spectroscopy measurements were performed on the RF-6000 Spectro fluorophotometer (Shimadzu, Gangnam-gu, Seoul, Korea). The TEM was performed with selected area diffraction (SAED), using a JEM-2010F electron microscope (JEOL, Tokyo, Japan) with an accelerating voltage of 200 kV. For the TEM, 0.1% sample solutions were dropped onto a mesh copper grid and the solvents evaporated on a hotplate. The particle size distribution was calculated based on the TEM images, using Image J software. The functional group of nanoparticles was analyzed through FTIR spectroscopy (PerkinElmer Spectrum Version 10.5.1, Korea) and the surface charge and stability of the Cys Au-EuNPs was also confirmed through a zeta potential analyzer (ELSZ-1000 common Version 5.22/3.00, Korea).