02661nas a2200193   4500008004100000245012100041210006900162260000800231300001000239490000800249520196700257100002202224700001702246700002302263700001702286700002002303700001502323856012902338       2018                        eng d00a Investigations on optical properties of ZnO decorated graphene oxide (ZnO@GO) and reduced graphene oxide (ZnO@r-GO)0 aInvestigations on optical properties of ZnO decorated graphene o  cMAY  a64-740 v7443 aThe present investigation is based on the production of reduced graphene oxide (r-GO) from the graphene oxide using Hummer's (GO) and improved Hummer's methods (IGO) at elaborated conditions, named as GO and IGO, respectively hereafter. In contrast to previously known techniques, the presented process does not generate toxic gas. Meanwhile, the reduction temperature can be easily controlled. This approach provides a more significant amount of hydrophilic oxidized graphene as compared to GO and IGO with the use of additional KMnO4. Thus synthesized IGO was used to produce r-GO by thermal treatment. The morphological characteristics show that the obtained samples have a wrinkled paper-like morphology with severely folded lines. However, r-GO has double layers and multilayer at the edges. All the products (GO, IGO, and r-GO) have been decorated with ZnO nanoparticles (NPs). The XRD patterns of ZnO@GO composites have confirmed the characteristic peaks of wurtzite ZnO indicating the formation of ZnO nanoparticles onto the surface of graphene. The microscopic studies confirm the random growth/decoration of ZnO NPs on the surface of GO/IGO/r-GO sheets. However, in IGO and r-GO, loading/growth of ZnO NPs are less as compared to ZnO@GO. Overall structural studies indicate the oxidation of graphite and reduction of graphene oxide into r-GO sheets and ZnO decoration. Upon UV excitations, a bright blue emission has been exhibited by the GO that originates from geminate recombination of localized e-h pairs in sp(2) clusters those primarily act as the luminescent centers. The noteworthy enhancement in the emission intensities after the incorporation of ZnO nanoparticles on the surface of GO is observed. The improved synthesis method and low-temperature reduction technique of GO may be essential for the large-scale production of r-GO as well as the construction of devices composed of ZnO@GO/IGO/r-GO. (C) 2018 Elsevier B.V. All rights reserved.1 aKumar, Pushpendra1 aSom, Sudipta1 aPandey, Mukesh, K.1 aDas, Subrata1 aChanda, Anupama1 aSingh, Jai  uhttps://library.ncl.res.in/content/investigations-optical-properties-zno-decorated-graphene-oxide-znogo-and-reduced-graphene01430nas a2200277   4500008004100000022001400041245013500055210006900190260000800259300001100267490000800278520046900286653002400755653002500779653002000804653002000824653002500844100002100869700002500890700002200915700001800937700001700955700002600972700002300998856013101021       2026                        eng d  a0167-577X00aLanthanide-activated single-phosphor white light emission via Bi3+ → Eu3+ energy transfer in Ca2Ga2GeO7 for next-generation LEDs0 aLanthanideactivated singlephosphor white light emission via Bi3   cMAY  a1402360 v4103 a<p>
	{We report the design and fabrication of Bi3+ and Eu3+ co-doped Ca2Ga2GeO7 (CGGO) phosphors for highperformance warm-white light-emitting diodes (LEDs). The phosphor exhibits efficient Bi3+ -&gt; Eu3+ energy transfer, as evidenced by spectral overlap, enhanced Eu3+ emission, and quenching of Bi3+ emission with increasing Eu3+ content. The emission color shifts from blue to red with increasing Eu3+, achieving near-white emission at 3% Eu3+ (x = 0.33</p>
10aBi3+/Eu3+ co-doping10aCa2Ga2GeO7 phosphors10aEnergy Transfer10aUV-excited LEDs10aWhite light emission1 aChethana, K., N.1 aKanojiya, Nitesh, S.1 aT.Parayil, Reshmi1 aSreevalsa, S.1 aDas, Subrata1 aMishra, Manish, Kumar1 aGupta, Santosh, K.  uhttps://library.ncl.res.in/content/lanthanide-activated-single-phosphor-white-light-emission-bi3-%E2%86%92-eu3-energy-transfer