Physical and optical properties of HfO 2 NPs – Synthesis and characterization in finding its feasibility in opto-electronic devices

Solvothermal‐assisted green synthesis of hybrid Chi‐Fe3O4nanocomposites: a potential antibacterial and antibiofilm material

“…The detection of C in the EDS spectrum also supports the presence of chitosan polymer in the prepared nanocomposite. Similar findings were reported by Manikantan et al , [52] who have documented the presence of C in the prepared copper‐chitosan NPs. The functional groups Cl and O signals in the EDS spectrum corresponds to the X‐ray emission from proteins bound to the NPs surface, which were then removed by centrifugation followed by repeated washing of the composite [58].…”

“…The obtained XRD analysis data of hybrid Chi‐Fe 3 O 4 nanocomposite was reliable with standard JCPDS reference code–75‐0033 [15, 28]. The crystallite size of the hybrid Chi‐Fe 3 O 4 nanocomposite was calculated by the Scherrer ((2)) [52] where D = average crystallite size, K ‐shape constant, λ – wavelength of X‐ray, β – full width half maximum (FWHM) of refection (in radians) located at 2 θ and θ – angle of reflection (in degrees). The crystalline size of the composite was determined to be 7.13 nm, derived from the FWHM of the corresponding peak at 311.…”

One-step upgrading of bio-based furfural to γ-valerolactone via HfCl4-mediated bifunctional catalysis

“…7B ) showed an obvious absorption peak, which has high agreement with the standard card PDF # 43-1017 of HfO 2 (ref. 48 ), indicating that the collected catalyst had good crystallinity after calcination. Then, the morphology of HfO 2 -(c) was studied by SEM and HR-TEM images.…”

“…47 The absorption peak at near 2975 cm À1 can be attributed to C-H stretching vibration, while the absorption peak at 1450 cm À1 is C-H bending vibration, and the absorption peak at 1056 cm À1 may be C-O stretching vibration. 48 These absorption peaks in HfO 2 -(c) were signicantly reduced, indicating that most of the humin in HfO 2 -(b) was removed aer the calcination. The absorption peaks at 1600 cm À1 and 530 cm À1 are the bending vibration and stretching vibration of the Hf-O bond, respectively, indicating that HfO 2 was indeed generated aer the catalyst was calcined.…”

“…47,49,50 Therefore, XPS diagrams of the collected catalyst and the HfO 2 -(c) were analyzed to explore the changes in the intensity of the acid-base sites in the catalyst. 48 In the MPV reduction reaction process, the Lewis acid site is mainly used to complete the transfer hydrogenation process, and the Lewis base site mainly plays the role in activating the hydroxyl group. Therefore, it was demonstrated that HfO 2 -(c) can effectively catalyze the production of FA from FF.…”