Tecnaitf 20 field emission hrtem

Transmission electron microscopy (TEM) and High-resolution TEM (HRTEM) images were obtained using an FEI TecnaiTF-20 field emission HRTEM operating at 200 kV. Samples were prepared by dropcasting of NP solution (both normal and acid treated) on 300-mesh amorphous carbon-coated copper grid and allowed to dry overnight at room temperature. Absorbance spectra were recorded to inspect the effect of acid treatment on spectral properties and concentrations of the NPs. To compare recyclability of the acid treated NPs to normal ones, we spectrophotometrically monitored bilirubin decomposition kinetics up to ten cycles. The experiment was started with equimolar concentration (10 µM) of bilirubin and catalyst for the first cycle and after every 15 min we added same dose of bilirubin into the reaction mixture. All absorption studies were performed using quartz cuvettes of either 0.4 cm (for serum samples) or 1 cm path length using a Shimadzu Model UV-2600 spectrophotometer.

TEM and HRTEM images were acquired using an FEI TecnaiTF-20 field emission HRTEM (OR, USA) operating at 200 kV. Sample preparation was done by drop-casting of aqueous C-Mn₃O₄ NP solution on 300-mesh amorphous carbon-coated copper grids (Sigma, USA) and allowed to dry overnight at room temperature. XRD patterns were obtained by employing a scanning rate of 0.02 s⁻¹ in the 2θ range from 10 to 80 by a PANalytical XPERT PRO diffractometer (Malvern, UK) equipped with Cu-Kα radiation operating at 40 mA and 40 kV. FTIR (JASCO FTIR-6300, Japan) was used to confirm the covalent attachment of the citrate molecules with the Mn₃O₄ NPs. For FTIR studies, powdered samples were blended with KBr powder and pelletized. KBr pellets were used as a reference to make the background correction.