A large red-shift in the photoluminescence emission of Mg 1−x Sr x TiO 3

Abstract

a b s t r a c tIn this letter, we report a detailed study of the influence of the synthesis and the optical properties of Sr-doped MgTO 3 powders synthesized via a polymeric precursor method. Our findings explain the shift in PL behavior from blue to near-infrared (NIR) emission, which is caused by different concentrations of deep and shallow defects in the samples and thus enables the design of differently colored materials. Additionally, the present results provide useful insights into designing a new series of NIR-emitting materials that have potential applications in emerging technologies ranging from optoelectronics to the biomedical field.

Controlling the Electronic, Structural, and Optical Properties of Novel MgTiO3/LaNiO3 Nanostructured Films for Enhanced Optoelectronic Devices

“…Moreover, the Raman-active modes located at 397 and 443 cm -1 were caused by the vibrational modes of the oxygen cage [20]. However, it can be seen from Figure 3(a) that the MTO thin film had ten Ramanactive modes (e.g., 5A g + 5E g ), as predicted in the literature [21][22][23][24][25][26][27]. This was attributed to high crystallization at short-range.…”

“…The other A g modes observed at approximately 390, 500, and 708 cm −1 , respectively, are related to the breathinglike vibrations of the six O atoms. However, by comparing the modes, it can be seen that they had different vibration directions in the octahedral configuration [25,26]. The E g mode typically observed at 275 cm −1 is attributed to the anti-symmetric breathing vibration of the O octahedron [25][26][27].…”

“…However, by comparing the modes, it can be seen that they had different vibration directions in the octahedral configuration [25,26]. The E g mode typically observed at 275 cm −1 is attributed to the anti-symmetric breathing vibration of the O octahedron [25][26][27]. As shown in Figure 3(a), the E g modes located at 320, 344, and 480 cm −1 can be described as the anti-symmetric breathing and twisting vibrations of the O octahedron with the cationic vibrations of both the Mg and Ti atoms parallel to the XY-plane [22,26], while the mode observed at approximately 620 cm −1 is likely associated with the Ti-O stretch [22].…”

“…The E g mode typically observed at 275 cm −1 is attributed to the anti-symmetric breathing vibration of the O octahedron [25][26][27]. As shown in Figure 3(a), the E g modes located at 320, 344, and 480 cm −1 can be described as the anti-symmetric breathing and twisting vibrations of the O octahedron with the cationic vibrations of both the Mg and Ti atoms parallel to the XY-plane [22,26], while the mode observed at approximately 620 cm −1 is likely associated with the Ti-O stretch [22]. Moreover, the MR spectrum of the polycrystalline MTO/LNO/Si heterostructure ( Figure 3(a)) exhibited all modes of both the MTO and LNO rhombohedral structures, which indicates that this sample prepared by the PLD method was structurally ordered at the shortrange.…”

Influence of Cu-doping on the structural and optical properties of CaTiO3 powders

“…In this context, it is well known that the polymeric precursor method is a simple, clean, and efficient approach to fabricate complex functional materials. It also offers excellent chemical homogeneity and precise stoichiometric control during heat treatments at relatively low temperatures [9,15,16]. Hence, this synthetic strategy substantially reduces the presence of segregated phases and does not require long annealing periods compared with other synthetic methods [9,15,16].…”