Due to the growing number of people infected with the new coronavirus globally, which weakens immunity, there has been an increase in bacterial infections. Hence, knowledge about simple and low-cost synthesis methods of materials with good structural and antimicrobial properties is of great importance. A material obtained through the combination of a nanoscale hydroxyapatite material (with good biocompatibility) and titanium dioxide (with good degradation properties of organic molecules) can absorb and decompose bacteria. In this investigation, three different synthesis routes used to prepare hydroxyapatite/titanium dioxide nanomaterials are examined. The morphology and semiquantitative chemical composition are characterized by scanning electron microscopy with energy dispersive X-ray analysis (SEM-EDX). The obtained materials’ phase and structural characterization are determined using the X-ray powder diffraction method (XRD). The crystallite sizes of the obtained materials are in the range of 8 nm to 15 nm. Based on XRD peak positions, the hexagonal hydroxyapatite phases are formed in all samples along with TiO2 anatase and rutile phases. According to SEM and TEM analyses, the morphology of the prepared samples differs depending on the synthesis route. The EDX analysis confirmed the presence of Ti, Ca, P, and O in the obtained materials. The IR spectroscopy verified the vibration bands characteristic for HAp and titanium. The investigated materials show excellent antimicrobial and photocatalytic properties.
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Atom Probe Tomography of Encapsulated Hydroxyapatite Nanoparticles
Hydroxyapatite nanoparticles (HAP NPs) are important for medicine, bioengineering, catalysis, and water treatment. However, current understanding of the nanoscale phenomena that confer HAP NPs their many useful properties is limited by a lack of information about the distribution of the atoms within the particles. Atom probe tomography (APT) has the spatial resolution and chemical sensitivity for HAP NP characterization, but difficulties in preparing the required needle‐shaped samples make the design of these experiments challenging. Herein, two techniques are developed to encapsulate HAP NPs and prepare them into APT tips. By sputter‐coating gold or the atomic layer deposition of alumina for encapsulation, partially fluoridated HAP NPs are successfully characterized by voltage‐ or laser‐pulsing APT, respectively. Analyses reveal that significant tradeoffs exist between encapsulant methods/materials for HAP characterization and that selection of a more robust approach will require additional technique development. This work serves as an essential starting point for advancing knowledge about the nanoscale spatiochemistry of HAP NPs.
more » « less- NSF-PAR ID:
- 10453690
- Publisher / Repository:
- Wiley Blackwell (John Wiley & Sons)
- Date Published:
- Journal Name:
- Small Methods
- Volume:
- 5
- Issue:
- 2
- ISSN:
- 2366-9608
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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