Observation of Mediated Cascade Energy Transfer in Europium-Doped ZnO Nanowalls by 1,10-Phenanthroline

Abstract

Embedding rare earth ions into a host material such as alkali halides, semiconductors, and metal oxides has been extensively studied, with the goal to improve performance in light emitting devices and biomedicine. Here, Europium-embedded ZnO nanowall structures have been achieved by a facile electrochemical deposition method. Upon Eu embedment, the nanowalls were found to become thicker and stacked. X-ray photoemission study revealed that Zn(OH) 2 was more dominant than ZnO near the surface and it confirmed that Eu(III) was uniformly distributed in the ZnO−Zn(OH) 2 core−shell structure. We also measured the photoluminescence spectra of as-grown, heat-treated and 1,10-phenanthroline surface-functionalized ZnO nanowalls samples, which led us to propose a unique cascade energy transfer model between ZnO, 1,10-phenanthroline, and Eu 3+ ion.

White and Tunable Emission from and Rhodamine B Detection by Modified Zinc Oxide Nanowalls

“…Upon Ar + sputtering, a new O 1s peak at 531.2 eV corresponding to ZnO emerges, and it becomes more prominent. The spectral evolution of the observed O 1s spectra confirms that the ZnO:Tb­(III) nanowalls follow the well-known growth mechanism of electrochemically deposited ZnO nanostructures . In addition, semiquantitative analysis of ZnO:Tb­(III) nanowalls using XPS survey spectra reveals that the concentration of Tb­(III) is ∼1.5 at.…”

“…The spectral evolution of the observed O 1s spectra confirms that the ZnO:Tb(III) nanowalls follow the well-known growth mechanism of electrochemically deposited ZnO nanostructures. 23 In addition, semiquantitative analysis of ZnO:Tb(III) nanowalls using XPS survey spectra reveals that the concentration of Tb(III) is ∼1.5 at. % for ZnO:Tb nanowalls obtained with a Tb(III) concentration of 10 mM.…”

“…Doping of trivalent rare earth (RE) transition metal ions into ZnO nanostructures has been conducted with the goal to improve their intrinsic physical properties, such as optical, electronic, and magnetic properties. − They are particularly attractive for potential application in visible optoelectronics because of their unique luminescence properties, such as hypersensitivity to the environment, narrow bandwidth, and long lifetime in the millisecond range. − Among the RE­(III) ions, europium and terbium are found to emit red and green luminescence, respectively. To date, most studies have focused on Eu­(III)-doped ZnO nanostructures. − Because the optical application of RE­(III)-doped ZnO nanostructures relies on the energy transfer from ZnO to RE­(III), Eu­(III) is less effective than Tb­(III) due to the larger energy difference between the conduction band minimum of ZnO and the emitting level for Eu­(III) ( 5 D 0 ) than that for Tb­(III) ( 5 D 4 ). Recently, Tb­(III)-doped ZnO [ZnO:Tb­(III)] nanostructured materials, such as nanorods, nanoparticles, nanocrystals, and microspheres, have been prepared by a number of methods including pulsed laser deposition and sol–gel and hydrothermal syntheses. ,,− The resulting ZnO:Tb­(III) nanostructures, however, were found to produce very weak lines as no or only trace characteristic emission originated from Tb­(III) was observed.…”

Bimetallic Au@M (M = Ag, Pd, Fe, and Cu) Nanoarchitectures Mediated by 1,4-Phenylene Diisocyanide Functionalization

“…As nanoscale architecture developed by surface engineering is of great interest, surface functionalization by organic adspecies has become the method of choice to modify a surface. , In this work, 1,4-phenylene diisocyanide (PDI, – CN + –C 6 H 4 –N + C – ) is selected as a coordinating agent between GNI and an overlayer electrodeposited metal. The PDI is one of the simplest molecules that has an isocynide group and it is well-known that an isocynide group could form σ-bonding with metal elements. − In particular, PDI reacts with gold, leading to the formation of −(Au–PDI) n – oligomers .…”

Synthesis, structural characterization, and photoluminescence properties of Eu3+‐doped Mg3‐xEux(BO3)2 phosphor

“…Eu 3+ ion is one of the most popular and efficient dopant to use for a wide range of applications such as laser and luminescent materials because europium ions show good emissions related to electronic transitions of 4f orbitals corresponding to the 5 D 0 ? 7 F J (J:1,2,3,4) transitions, [24][25][26][27][28][29][30][31][32][33][34][35][36][37][38] because of these transitions, the Eu 3+ -doped compounds have the high luminescence efficiency. Moreover, magnesium borates are good candidates as host structure owing to their low synthetic temperature and simple preparation process.…”