Physico-chemical characterization of sterilized Co2.25Fe0.75O4 nanoparticles by XPS / HAXPES / SEM

Here a dataset of XPS, HAXPES and SEM measurements for the physico-chemical characterization of sterilized nanoparticles is presented. The measurements are part of the H2020 project “NanoSolveIT”.

Co_2.25Fe_0.75O₄ nanoparticles were provided by Promethean Particles and treated differently by project partners from the University of Birmingham (EMR identifier in the project: ERM00000406, ERM00000448, ERM00000427).

The particles were treated by different sterilization methods (autoclave or microwave) and BSA was or was not added as stabilizer. This finally leads to five different samples: pristine, autoclave, microwave, autoclave with BSA, microwave with BSA.

Prior to the measurements, the samples were prepared from the solution as drop cast on Si wafers.  First SEM and EDS measurements were performed, followed by XPS and HAXPES measurements on the same samples. Here at first survey spectra were recorded followed by high resolution spectra. For XPS / HAXPES several Si-wafers were mounted together on one platen. The platen was left in the intro chamber of the instrument for several hours before the measurement started.

Equipment:

SEM images were acquired with a Supra 40 (Zeiss) SEM equipped with a Quantax 400 (Bruker) SDD EDS spectrometer.

For X-ray spectroscopy experiments, a combined XPS / HAXPES spectrometer (Quantes from ULVAC-PHI) was used, where XPS is measured at 1486.6 eV (monochromatic Al Kα source) and HAXPES at 5414.9 eV (monochromatic Cr Kα source). Here it is possible to perform the measurements at the exact same position.

Data:

For SEM, the data are given in .tif format. For XPS / HAXPES the raw data are given as .spe (PHI format) and .npl (VAMAS format) files. The measurement conditions are given in the data files.

Naming of data:

SEM: sample_treatment (n), with n a consecutive number.

XPS / HAXPES:   For the .spe files Pn.m.o.sample_treatment and for the corresponding .npl files: m.npl with Pn: platen-number, m: spectrum number (order of the measurements); o: point-number, of the position on the sample, sample_treatment with "m" for microwave and "a" for autoclave.

The authors thank Sigrid Benemann, who performed the SEM measurements.