Herein, the first study on the scintillation properties of CsCu 2 X 3 and Cs 3 Cu 2 X 5 (where X: Cl − , Br − , I − ) is presented, describing their charged particle‐induced luminescence involving electrons, protons, α‐particles, and heavy ions, as well as revealing their capabilities on the timing and spectroscopic evaluation of single‐particle events. The thin layers are prepared with a simple and cost‐effective deposition procedure, without the incorporation of external dopants, exploiting the intrinsic radiative recombination observed in low‐dimensional perovskites. The combined effect of the high binding energy and localized stability of self‐trapped excitons, large Stokes shift, defect tolerance, and the high excitation density along the particle track leads to the emergence of boosted scintillation pulses. The observations demonstrate the first use of inorganic thin‐film scintillators with optical pulse characteristics and light yield competitive with doped single crystal scintillators, while also providing improved structural and functional stability under extreme environmental conditions.

To ensure clinical success, the implant and the surrounding bone tissue must not only be integrated, but also must not be suspected of infection. In this work, an antibacterial and bioactive nanostructured calcium silicate (CaSi) layer on titanium substrate by an electrospray deposition method was prepared, followed by annealing at 700, 750 and 800 °C to improve the bonding strength of the CaSi coating. The phase composition, microstructure and bonding strength of the CaSi coatings were examined. Human mesenchymal stem cells (hMSCs), Gram-negative Escherichia coli (E. coli) and Gram-positive Staphylococcus aureus (S. aureus) species were used to analyze the osteogenic and antibacterial activity of the coatings, respectively. Experimental results showed that the as-prepared CaSi coating was mainly composted of β-dicalcium silicate phase with a particle size of about 300 nm. After annealing, the thickness of the oxidation reaction layer increased obviously from 0.3 μm to 1 μm with increase in temperature, which was confirmed by the cross-sectional morphology and element depth profile. The bonding strength of the coating annealed at 750 °C (19.0 MPa) was significantly higher (p < 0.05) than that of the as-prepared coating (4.4 MPa) and the ISO 13,779 standard (15 MPa). The results of antibacterial efficacy and stem cell osteogenesis consistently elaborated that the 750 °C-annealed coating had higher activity than the as-prepared coating and the Ti control. It is concluded that after annealing at 750 °C, the CaSi nanoparticle-coated Ti implant had good bond strength, osteogenic and antibacterial activity.

Charged-particle induced radioluminescence (RL) of CsPbBr3 (CPB) perovskite quantum dots (QD) in their clustered state was investigated using alpha-particles from a radiation source. The RL response was analyzed with photomultiplier tubes (PMT) combined with the pulse-digitization technique, which enabled the evaluation of time-resolved waveforms for individual alpha-radiation events. The rising and decay transition times of electric pulses were found very close to the instrumental limitation, while orders of magnitude shorter than typically measured in conventional inorganic scintillators. Based on the statistical analysis of timing characteristics, our study assessed the potentials of employing perovskite nanomaterials in precise timing applications as demonstrated in a comparative measurement with a CsI(Tl) scintillator. The distribution of pulse charge was converted to luminescence intensities, which were fitted with Monte Carlo simulations giving an estimate of 2.95 photon/keV for the RL yield and 29.2% for detection efficiency (DE), referring to our mean cluster thickness of 5 QD layers. (C) 2021 The Author(s). Published by Elsevier B.V.

Knowledge of an exact value of the relative detection factor (RDF) is important for correct quantification of measurements of Secondary Neutral Mass Spectrometry (SNMS). A special crystal ingot was grown from the vapor phase to determine this coefficient for PbTe binary telluride. Sputtering of the samples was carried out by Ar+ ions with energy of 350 eV. High structural quality of the crystal grown from vapor phase allowed minimizing the density of the surface structures forming on the sputtered surface and the dimple relief of the surface. The magnitude of RDF is determined and the analytical expression is given for its energy dependence, taking into account correction caused by the impact of the transmission factors which determine the fractions of emitted Pb and Te atoms collected into the mass spectrometer.

Titanium and its alloys have been used as implant materials. Non-ideal osseointegration of the implant materials has facilitated the development of the bioactive coatings on the implant surfaces. In this work, the bioactive calcium silicate (CaSi) powder prepared in a green synthesis route was used to cover the surface of Ti implants by a facile electrospray deposition method. Post annealing in air was also applied to form the oxidation layer on the Ti surface with the aim of increasing the bond strength between the CaSi coating layer and Ti substrate. For the characterization of the coatings several analytical methods such as X-ray diffraction, scanning electron microscopy, secondary neutral mass spectrometry, and Raman-spectroscopy were used, in addition to the measurement of bond strength and corrosion resistance. The results indicated a uniform CaSi layer with a thickness of about 1 pm deposited on the Ti substrate. Annealing in the range of 700-900 degrees C in air resulted in the formation of rutile phase of TiO2; more importantly, annealing at 800 degrees C did not significantly affect the composition of the CaSi layer consisting of beta-Ca2SiO4. The bond strength between the coating layer and Ti substrate can be remarkably enhanced at an annealing temperature of 700 or 800 degrees C compared with the as-prepared coating without annealing. The annealed coatings had a better corrosion resistance than the as-prepared coating. It is concluded that the electrospray method associated with the post-annealing can be successfully used for the deposition of a CaSi layer with a defined structure and composition on titanium implants.

Amorphisation effect on the surface of SnTe and GeTe samples under low Ar+ ion energy sputtering (160 eV) has been firstly observed. Scanning electron microscopy and Raman spectroscopy methods were used for the investigation. Microscope images show that ion bombardment changes significantly the morphology of SnTe and GeTe sample surfaces. Comparative Raman spectroscopy studies of the as-prepared and sputtered surfaces revealed that sputtering changes not only the surface morphology, but also the crystal structure of samples. Due to sputtering, the initial crystalline GeTe sample surface completely changed to amorphous, while the SnTe sample surface changed to a mixed amorphous-crystalline structure. This means that on the surface of IVB group binary tellurides an amorphisation can be evoked by low energy Ar+ ion bombardment, up to a few hundred electron volts energy. (C) 2018 Elsevier B.V. All rights reserved.