Enhancing the Up-conversion luminescence using All dielectric Three-Dimensional multiscale anodized aluminum oxide nanowire structure

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• An unsophisticated cost-effective chemical process was performed to fabricate all dielectric 3D AAO nanowire structures with unique topographies. • Core/shell NaYF 4 :Yb(49%), Tm(1%)/NaYF 4 UCNPs were synthesized using sophisticated chemical method in laboratory. • Fabricated AAO nanowire substrate with 5 µm wirelength, which facilitate the multiple scattering, Fabry-Perot resonances, and the guided modes inside the nanowires, provide UCL enhancement up to ~115 fold via densely populated intermediate state. • The quenching of UCL intensity in AuNR due to non-radiative transition is also well observed. Light management at nanometric dimension for boosting the enhancement of photo luminescence from Lanthanide doped up-conversion nanoparticles (UCNPs) has evidenced epochal advancement attributed to their conspicuous emission properties and plethora of potential applications. In this work, a multiscale funnel shape three dimensional (3D) anodized aluminum oxide (AAO) nanowire topography is explored to improve up-conversion luminescence (UCL) of synthesized core shell (C/S) NaYF 4 :Yb 3+ ,Tm 3+ /NaYF 4 UCNPs dispersed in chloroform. The different hexagonally arranged AAO topographies, based on cost-effective and modified self-aggregation fabrication method, are presented. These unique topographies of nanowire structures provide archetypal for enhanced UCL and have been investigated to study the effect of light management in detail. The systematic studies indicate that UCL enhancement is substantiated by the prolonged light path due to multiple scattering, and guided modes in the length of nanowire structures with the modified surface topography hoisted by capillary force inside the nanowires. The length of the nanowire and structure’s topographies are endorsed as structural parameters to tune the reflection as well as resonance mode for tuning the enhancement. The overall UCL enhancement for an optimized wire length and surface topography of AAO substrate is found to be ∼ 115 fold in ultra-violate regime at low excitation power density.