Synthesis of Fe:ZnSe nanopowders via the co‐precipitation method for processing transparent ceramics

Abstract

Fe:ZnSe nanopowders were synthesized via the co‐precipitation method for fabricating transparent ceramics. FexZn1−xSe (0.00 ≤ x ≤ 0.06) powders that were calcined at 400°C yielded a single‐phased cubic ZnSe, but when the calcination temperature was raised to 500‐600°C, ZnO phase was created. Introduction of pressure could avoid appearance of ZnO. XRD Scherrer analysis revealed a monotonic increase in lattice parameter with increasing Fe2+ content. The average powder particle size increased with calcination temperature from several nanometers at 80°C to hundreds of nanometers at 600°C. Attempts to pressurelessly sinter ZnSe powders resulted in the partial decomposition of ZnSe, thus spark plasma sintering was employed to sinter Fe0.01Zn0.99Se transparent ceramics with pure ZnSe phase composition, which could be well sintered at 950°C for 30 minutes under an applied pressure of 60 MPa. SEM observations of the polished and thermally etched microstructure of the ceramic revealed a dense microstructure with average grain size of approximately 35 μm, and a few micropores were observed at the grain boundaries. The transparent ceramic exhibited good transmittance in the mid‐far infrared range, with the highest transmittance 57% at 12 μm. This paper confirmed the scheme of synthesis of Fe:ZnSe nanopowders by liquid‐phase co‐precipitation method for sintering transparent ceramics.

Microstructure development and optical properties of Fe:ZnSe transparent ceramics sintered by spark plasma sintering

“…All rights reserved had successfully substituted for Zn 2+ in the ZnSe lattice. 24 Fig. 2 The lattice parameter a=5.6677 Å by the Rietveld refinement (as shown in Fig.…”

A Review of Cr2+ or Fe2+ Ion-Doped Zinc Sulfide and Zinc Selenide Ceramics as IR Laser Active Media

“…However, both the entrapment of the mother liquor during crystallization and the adsorption of chemical reaction products and other impurities are unavoidable. The transmission spectrum of synthesized ZnS particles contains absorption bands of hydroxyl, hydrocarbon, carboxyl, alcohol groups, and oxygen-containing impurity defect centers [62,[66][67][68]80,85,88]. Therefore, various types of thermal treatment of powders have been developed, taking into account the optimal relationship between impurity removal, particle growth, agglomeration, and phase transitions occurring in the process.…”

“…Therefore, various types of thermal treatment of powders have been developed, taking into account the optimal relationship between impurity removal, particle growth, agglomeration, and phase transitions occurring in the process. Annealing is typically performed in the temperature range of 500-900 • C under vacuum [67,80,85], argon [79,83,84,[88][89][90], or hydrogen sulfide H 2 S/N 2 atmosphere [62][63][64]86]. Effective purification from oxygen-containing impurities begins at ~600 • C [62].…”

“…The fabrication of ZnSe powders by chemical precipitation from solutions is usually carried out using NaHSe as a source of selenium ions [88,89]. Oxygen contamination is also an issue for the ZnSe; it is present in the powders in significant amounts and is detected both by XRD analysis and in the transmission spectrum of the synthesized ceramics [88].…”

“…Second, the presence of impurities can increase the non-radiative transition probabilities, reducing the luminescence quantum yield, rais ing the lasing threshold, or making it impossible to achieve population inversion at all Therefore, laser ceramics should have both high structural perfection and chemical purity preferably 99.99% or better; in particular, limited impurities that have electronic transi tions in the laser wavelength range should be at the ppm level or less. To create a laser material, ZnSe or ZnS particles are doped with iron or chromium The introduction of these metals is possible by solid phase diffusion into prepared zinc chalcogenide powders [80,101,105,110] as well as during synthesis [79,80,88,89,111,112] In [57], a powder for subsequent consolidation was obtained by mechanical grinding in an agate mortar of pure ZnSe with a ZnSe-CrSe mixture of different concentrations (0.01 0.03, 0.05, and 0.1 mol%). The particle size did not exceed 10 µm.…”