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Artificial red lights of good quality are essential for indoor plant growth as it has a wide spectrum effects on photosynthesis rate and photomorphogenic processes of organic plant growth cycle. In present work we report on Eu3+ doped Bi4Si3O12 (BSO) phosphor for spectroscopic implication in smart plant grow LEDs. Eu3+ activated series of Bi4Si3O12 phosphor have been prepared via traditional solid-state reaction method. Crystal structure and phase formation characterization is determined by using X-ray diffraction (XRD). Photoluminescence spectra of prepared phosphor shows broad excitation spectra ranging from 200 to 530 nm. The optimal Eu3+ doping concentration observed at 3 mol%. Emission spectra observed under the excitation of 270 nm shows broad emission band at 469 nm along with other characteristic peak at 500 nm-710 nm. Observed emission peaks at 622 nm, 656 nm and 702 nm were chosen opt for plant grow lights. The phytochrome PFR absorption spectra of plants matches well with the emission band of our Eu3+ doped BSO phosphor and can be considered as a viable choice for solid state lighting and plant grow light LEDs.

Europium doped strontium meta-silicate (namely SrSiO3:Eu3+) phosphor was prepared by a high temperature solid state reaction method. The sintered SrSiO3:Eu3+ phosphor possesses a monoclinic structure by the XRD. Energy dispersive X-ray spectrum (EDS) confirms the presence of elements in the desired sample. Thermoluminescence (TL) kinetic parameters such as activation energy (E), order of kinetics (b), and frequency factor (s) were calculated by the peak shape method. The orange–red emission was shown to originate from the 5D0–7FJ (J = 0, 1, 2, 3, 4) transitions of Eu3+ ions as the sample was excited at 396 nm. The SrSiO3:Eu3+ phosphor with almost pure orange-red color purity (99.62%) shows the quantum efficiency of 10.2% (excited by 396 nm), which is higher than those of commercial red phosphors Y2O3:Eu3+ and Y2O2S:Eu3+ with quantum efficiencies of 9.6% (excited by 394 nm) and 4.2% (excited by 395 nm), respectively. Mechanoluminescence (ML) intensity of the SrSiO3:Eu3+ phosphor was also found to increase linearly with increasing the impact velocity of the moving piston, suggesting that the discussed phosphor can be used as a stress sensor.

CaZrO3:xEu3+ (x = 1.0, 2.0, 3.0, 4.0, and 5.0 mol%) phosphors were successfully prepared by a solid state reaction method. The crystal structure of sintered phosphors was hexagonal phase with space group of Pm-3m. The near ultra-violet (NUV) excitation, emission spectra of the CaZrO3:xEu3+ phosphors were composed of sharp line emission associated with the transitions from the excited states 5D0 to the ground state 7Fj (j = 0, 1, 2, 3, 4) of Eu3+. The results indicated that CaZrO3:xEu3+ might become an important orange-red phosphor candidate for use in white light emitting diodes (WLEDs) with near-UV LED chips. The mechanoluminescence (ML) intensity increases linearly with increasing impact velocity of the moving piston, suggesting that the sintered phosphors can also be useful as a stress sensor.

Nanostructures, crystalline Zinc oxide powder were synthesized by mixing Zinc chloride (0.04M) and sodium hydroxide (0.08M) using chemical route method. 0.001M molar concentrations of TEA (Tri ethanolamine) in aqueous solution used to the growing reaction solution. The powder samples are annealed at 190 °C. The experimental results indicate a successful growth of Zinc oxide in solid form which is not observed ever before. XRD, SEM, TEM and PL were performed to characterize the morphology, growth and optical nature of the samples. The some Rod and particle like morphology of zinc oxide has been examined by transmission electron microscopy. The particle size was found to vary from 7 to 21 nm. The room temperature PL spectra exhibits low intensity UV emission peak at 407 nm and blue emission band around 484 nm.

A new orange–red europium doped di-calcium magnesium di-silicate (Ca2MgSi2O7:Eu3+) phosphor was prepared by the traditional high temperature solid state reaction method. The prepared Ca2MgSi2O7:Eu3+ phosphor was characterized by X-ray diffractometer (XRD), transmission electron microscopy (TEM), field emission scanning electron microscopy (FESEM) with energy dispersive x-ray spectroscopy (EDX), fourier transform infrared spectra (FTIR), photoluminescence (PL) and decay characteristics. The phase structure of sintered phosphor was akermanite type structure which belongs to the tetragonal crystallography with space group P4¯21m, this structure is a member of the melilite group and forms a layered compound. The chemical composition of the sintered Ca2MgSi2O7:Eu3+ phosphor was confirmed by EDX spectra. The PL spectra indicate that Ca2MgSi2O7:Eu3+ can be excited effectively by near ultraviolet (NUV) light and exhibit bright orange–red emission with excellent color stability. The fluorescence lifetime of Ca2MgSi2O7:Eu3+ phosphor was found to be 28.47 ms. CIE color coordinates of Ca2MgSi2O7:Eu3+ phosphor is suitable as orange-red light emitting phosphor with a CIE value of (X = 0.5554, Y = 0.4397). Therefore, it is considered to be a new promising orange–red emitting phosphor for white light emitting diode (LED) application.

Europium doped di-strontium magnesium di-silicate phosphor namely (Sr2MgSi2O7:Eu3+) was prepared by the traditional high temperature solid state reaction method. The phase structure of sintered phosphor was akermanite type structure which belongs to the tetragonal crystallography with space group P42¯1m, this structure is a member of the melilite group and forms a layered compound. The EDX and FTIR spectra confirm the present elements in Sr2MgSi2O7:Eu3+ phosphor. Photoluminescence measurements showed that the phosphor exhibited strong emission peak with good intensity, corresponding to 5D0 → 7F2 (613 nm) red emission and weak 5D0 → 7F1 (590 nm) orange emission. The excitation spectra monitored at 613 nm show broad band from 220 to 300 nm ascribed to O–Eu charge-transfer band (CTB) centered at about 269 nm, and the other peaks in the range of 300–400 nm originated from f–f transitions of Eu3+ ions. The strongest band at 395 nm can be assigned to 7F0 / 5L6 transition of Eu3+ ions due to the typical f–f transitions within Eu3+ of 4f6 configuration.

The present paper reports the thermoluminescence (TL) properties of combustion synthesized Ti doped ZrO2 nanophosphors the effect of annealing on TL glow curve was also studied. The structural characterizations were done by X-ray diffraction technique (XRD), composition by Fourier transformation infrared spectroscopy and surface morphology was determined by field emission gun scanning electron microscopy (FEGSEM) technique. The prepared phosphor annealed at 600 °C, 700 °C, 800 °C and 900 °C and its thermoluminescence glow curve were recorded. The heating rate effect, the thermal quenching as well as the annealing temperature of the material were optimized for the TL glow curve of the sample. The TL glow curves for different UV, gamma doses and for Ti concentration were studied. The TL glow curve of prepared samples have glow peak at 173 °C. The kinetic parameters was calculated by Computerized glow curve convolution technique (CGCD) technique. Fading and reusability studies of the nanophosphor further confirmed the phosphor's suitability for radiation dosimetry. The main conclusion is that Solution Combustion Synthesis is one of the appropriate method for synthesis of Ti doped ZrO2 nanophosphors, which is suitable for temperature sensing applications, the post-synthesis annealing regime being one of the parameters that can affect the intensity and other parameters.