Investigations on structural, photoluminescent, and photometric properties of poly(vinyl alcohol)-capped Mn doped-ZnO nanoparticles for white light emission

Abstract

In this paper, luminescent Mn-doped ZnO nanoparticles (NPs) and poly(vinyl alcohol) (PVA) capped Mn-doped ZnO nanocomposite materials were successfully synthesized by the chemistry route. The studied results indicate that the diffraction peaks of Mn-doped ZnO NPs (2, 4, and 7% Mn) are slightly shifted to the lower 2θ degree angle compared to undoped-ZnO NPs. In contrast, PVA capped Mn-doped ZnO nanocomposite shows a systematic shift of X-ray diffraction (XRD) peaks at larger diffraction angles. These samples fluoresce strongly in the visible wavelength of 380–700 nm. The near-infrared (NIR) emission bands in the 740 nm–1100 nm range are due to the shift of XRD peaks diffraction and the transition between defect states within the ZnO crystal. Photometric and chromatic parameters of PVA capped-2%Mn doped-ZnO NPs are CIE (x, y) ≈ (0.3769, 0.3987), CCT ≈ 4238 (K), Duv = 0.0110, CRI (Ra) = 80, CQS = 84, LER = 164 (lm/Wotp), and S/P ratio = 1.70. Luminescent PVA capped ZnO NPs possess CIE (x, y) ≈ (0.3598, 0.3748), CCT ≈ 4592 (K), Duv = 0.0057, CRI (Ra) = 85, CQS = 87, LER = 207 (lm/Wotp), and S/P ratio = 1.83. The studied results indicate that these luminescent materials are suitable for developing a white light emission layer in the structure of light-emitting devices.