2100 microscope

X–ray diffraction (XRD) patterns were recorded on a Shimadzu XRD–7000S instrument in reflection mode with Cu Kα radiation. The accelerating voltage was set at 40 kV with 30 mA current (λ = 1.542 A°). Diffraction patterns were obtained over the range of 2‒70^o with a scanning rate of 5° min^–1. Field emission (FE)–scanning electron microscopy (SEM) analyses were performed on a Hitachi SU–8010 scanning microscope with an accelerating voltage of 5.0 kV. Powder samples were spread on carbon tape adhered to the SEM stage. Before observation, the samples were sputter coated with a thin platinum layer to prevent charging and to improve the image quality. Transmission electron microscope (TEM) analyses were performed on a JEOL 2100 microscope with an accelerating voltage of 400 kV. Samples were dispersed in ethanol with sonication and then casted onto copper TEM grids. Measurements of ζ‒potential were recorded with a Malvern Zetasizer Nano–Z system, after the particles were dispersed in water via ultrasonication for 30 min.

XRD patterns were collected through an XRD‐7000S diffractometer equipped with a Cu K_α1 Radiation (λ = 1.5406 Å). Scanning electron microscopy observations were performed on a JEM7600F microscope at 15 kV. TEM observations were carried out on a JEOL2100 microscope at 200 kV. Raman spectra were recorded on a Renishaw Invia spectrometer by using Ar+ laser of 514.5 nm. The nitrogen adsorption and desorption isotherms were recorded at 77 K by using a Micromeritics ASAP 2020 analyzer and the surface area was calculated using the BET method. XPS spectra were recorded on an Axis Ultra DLD system with a monochromatic Al K_α X‐ray source.

Silica-coated SPIONs were synthesized by coprecipitation from aqueous solutions of iron salts, as described in detail elsewhere [81 (link),82 (link),83 (link)]. Then, the surface of the NPs was functionalized by addition of citric acid and coated with a ~4 nm thick silica shell as described in our published studies [84 (link),85 (link),86 (link),87 (link)]. The silica-coated SPIONs were characterized by TEM, DLS, and zeta potential measurements. Samples for TEM analysis were prepared by drying the aqueous suspension of silica-coated SPIONs at room temperature on a transparent carbon film on a copper grid, and images were acquired using a JEOL 2100 microscope (JEOL Ltd., Tokyo, Japan). Suspension of silica-coated SPIONs in serum-free medium (c = 1 mg/mL; pH = 7.91) was monitored by electrokinetic measurements of zeta potential (Anton Paar GmbH, Litesizer 500, Graz, Austria) and hydrodynamic diameter distribution was determined by DLS (Anton Paar GmbH, Litesizer 500, Graz, Austria).

The dimension and microstructure of the printed inorganic nanocrystal-based porous materials were imaged using OM and SEM, respectively. Optical imaging was performed using an OM (BX51M, Olympus). SEM (including tilted views) and EDS mapping image were collected using a field-effect SEM (Nova NanoSEM, FEI and SU7000, Hitachi High-Tech) with a 10 kV (SEM image) and 20 kV (EDS mapping image) electron beam. The CCD images and movies were obtained using a CCD camera (MicroPublisher 5.0 RTV, QImaging). The TEM images were obtained at 200 kV using a JEOL-2100 microscope (JEOL). HR-TEM, HAADF-STEM imaging, and spectral imaging based on STEM-EDS were performed at 200 kV using a JEM-2100F (JEOL) and JEM-ARM300F microscope (JEOL). For analysis, the printed objects were crushed and suspended in methanol by ultrasound for 15–120 s, depending on their dispersing ability. The cross-sectional TEM sample of Ag filament was prepared using a focused ion beam (FEI Helios NanoLab 450). Bright-field transmission electron microscopy (BF-TEM) and scanning TEM images were obtained using a chromatic aberration (Cs) corrected TEM (Grand ARM300F, JEOL) at an acceleration voltage of 160 kV.

¹H- and ¹³C-NMR spectra measurements were recorded in a Varian Mercury 300 MHz spectrometer (Varian, Palo Alto, CA, USA) at 30 °C. Powder X-ray diffraction (XRD) was performed at room temperature with a Bruker D4 Endeavor X-ray powder diffractometer (Bruker AXS, Madison, WI, USA) by using Cu-K radiation. A sample of the dried gel was placed on a sample holder and data were collected for 2θ values between 2 and 40° with a step size of 0.03° and a time step of 10 s. Circular dichroism (CD) spectra were recorded in a Jasco J-810 spectropolarimeter (Jasco, Peabody, MA, USA). The measurements were performed on pellets composed by 1 mg of lyophilized gel and 50 mg of KBr. For transmission electron microscopy (TEM), a small portion of the gel was placed on a nickel grid coated with carbon and allowed to dry on air. Images were recorded in a JEOL 2100 microscope (JEOL, Peabody, MA, USA). Catalytic enantiomeric excess was determined by HPLC (Agilent Technologies, Santa Clara, CA, USA) using a Chiralpack IA column, λ = 254 nm, Ethanol/Hexane (v/v: 15/85), flow rate = 1.5 mL/min.