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Photoluminescence of combinatorically sputtered Al₂O₃–Y₂O₃ thin films with a Cr³⁺ and Nd³⁺ co-doping concentration gradient

Derksen, M. (author), Bizinoto Ferreira Bosco, G. (author), Muller, Timo (author), van der Kolk, E. (author)

The characterization of a wide range of luminescent thin films can be a long and tedious endeavor. With reactive combinatorial sputtering of multiple metal targets, it possible to fabricate thin films with a gradient in composition simply by not rotating the substrate. In this work, combinatorically sputtered thin films of Cr³⁺ and...

journal article 2024

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Evaluating the Tm2+ 4f125d1 → 4f13 and 4f13 → 4f13 Luminescence and Quenching Dynamics in Orthorhombic BaCl2

Plokker, M.P. (author), Vlaar, S.A. (author), Bakx, A.H.J. (author), van der Kolk, E. (author), Dorenbos, P. (author), Hintzen, H.T.J.M. (author)

The luminescence properties of Tm2+-doped BaCl2 with an orthorhombic structure have been studied as a function of temperature and compared to other Tm2+-doped chlorides. In addition to the 2F5/2 → 2F7/2 (4f13 → 4f13) line emission, two 4f125d1 → 4f13 band emissions are observed at 20 K that can be ascribed to the spin-allowed (3H6,5d1)S=1/2 →...

journal article 2023

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Metal-insulator multilayer precursors for enhanced Sm²⁺ absorption and Tm²⁺ luminescence in SiAlO thin films prepared by magnetron sputtering

Bizinoto Ferreira Bosco, G. (author), van den Biesen, J. K. (author), Boers, C. D. (author), Simone, G. (author), Kao, C.C. (author), Tichelaar, F.D. (author), Boshuizen, B. (author), van der Kolk, E. (author)

Silicon-aluminum-oxigen (SiAlO) coatings doped with Sm²⁺ and prepared by reactive magnetron co-sputtering of Si, Al, and Sm targets, are attractive for luminescence solar concentrator applications but suffer from the low absorption between 300 and 600 nm. This article reports that the main cause of low absorption is a high...

journal article 2022

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The potential of transparent sputtered NaI:Tm²⁺, CaBr₂:Tm²⁺, and CaI₂:Tm²⁺ thin films as luminescent solar concentrators

Merkx, E.P.J. (author), Plokker, M.P. (author), van der Kolk, E. (author)

The parameters governing the performance of a luminescent solar concentrator (LSC) are determined for sputtered thin-films of NaI:Tm²⁺, CaBr₂:Tm²⁺, and CaI₂:Tm²⁺. These parameters are determined by using six gradient thin film material libraries, combinatorially sputtered from metallic...

journal article 2021

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Optical and structural characterization of Tm₂O₃, TmN, and TmO_xN_y thin films grown by direct-current reactive magnetron sputtering

Meeuwissen, A.A. (author), Bizinoto Ferreira Bosco, G. (author), van der Kolk, E. (author)

This paper reports the fabrication and characterization of several thulium oxide and nitride thin films grown by reactive magnetron direct-current sputtering. Hysteresis curves of the Tm emission spectra of the sputtering plasma versus the flow of N₂ or O₂ around the Tm-metal target were monitored. Emission spectra of...

journal article 2021

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Photoluminescence and excited states dynamics of Tm²⁺-doped CsCa(Cl/Br)₃ and CsCa(Br/I)₃ perovskites

Plokker, M.P. (author), Biner, D. A. (author), Dusoswa, N. (author), Dorenbos, P. (author), Krämer, K. W. (author), van der Kolk, E. (author)

In this study, we systematically vary the Cl/Br and Br/I ratios in CsCaX₃:Tm²⁺ (X = Cl, Br, I) and hereby gradually shift the positions of the Tm²⁺ 4f¹²5d¹-levels as relative to the two 4f¹³ levels. At low temperatures up to five distinct Tm²⁺ 4f¹²5d<sup>1...

journal article 2021

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Experimental and numerical analysis of Tm²⁺ excited-states dynamics and luminescence in CaX₂ (X = Cl, Br, I)

Plokker, M.P. (author), van der Knijff, I.C. (author), de Wit, A.V. (author), Voet, B. (author), Woudstra, T. (author), Khanin, V. (author), Dorenbos, P. (author), van der Kolk, E. (author)

The prospect of using Tm²⁺-doped halides for luminescence solar concentrators (LSCs) requires a thorough understanding of the temperature dependent Tm²⁺ excited states dynamics that determines the internal quantum efficiency (QE) and thereby the efficiency of the LSC. In this study we investigated the dynamics in CaX<sub...

journal article 2021

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Concentration and temperature dependent luminescence properties of the SrI₂-TmI₂ system

Plokker, M.P. (author), Hoogsteen, W. (author), Abellon, R.D. (author), Krämer, K. W. (author), van der Kolk, E. (author)

The concentration dependent luminescence of the SrI₂-TmI₂ system was investigated. For Tm²⁺ concentrations up to 5 mol %, the quantum efficiency (QE) of the ²F_5/2→²F_7/2 emission exhibits a constant value above 50%. The QE drops for higher Tm²⁺...

journal article 2020

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Towards Tm²⁺ in sialon thin films grown by sputtering using the gradient deposition

Bizinoto Ferreira Bosco, G. (author), van der Kolk, E. (author)

The valence stability parameter (E_Ff), defined as the difference between the charge transfer energy to the host intrinsic Fermi energy, was used as criterion to analyze the capability of different host materials within the SiAlON class to stabilize divalent thulium. Available data on charge transfer energies and optical bandgap...

conference paper 2020

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4f→5d and anomalous emission in Yb²⁺ doped NaI, SrI₂ and LaI₃ powders prepared by rapid melting and quenching in vacuum

Hendriks, M.H.P. (author), van der Kolk, E. (author)

The temperature dependent luminescence properties of Yb2+ doped in NaI, SrI2 and LaI3 powders, prepared by a fast synthesis method involving the rapid melting and quenching in vacuum are reported. The 4f→5d excitation and emission spectra obtained for SrI2:Yb2+ were found to be in accordance with earlier work validating the synthesis methods. In...

journal article 2019

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Modelling and optimization of UV absorbing photovoltaic windows using a thin film AlN:Eu³⁺ luminescence library

Merkx, E.P.J. (author), Lensvelt, T.G. (author), van der Kolk, E. (author)

Building-integrated photovoltaics are drawing much attention to make the built environment self-sufficient in terms of electricity. Luminescent solar concentrators (LSCs) can provide this electricity generation when used as photovoltaic windows. Paramount to an efficient LSC are non-overlapping absorption and emission spectra, to avoid self...

journal article 2019

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Temperature dependent relaxation dynamics of luminescent NaX:Tm²⁺ (X=Cl, Br, I)

Plokker, M.P. (author), van der Kolk, E. (author)

In recent years, Thulium in its 2 + oxidation state has been identified as candidate dopant in halide hosts for luminescent solar concentrators. Yet, some of its luminescent properties with regard to these applications remain unexplored. In this study we report on the temperature dependent photo-luminescent behaviour of NaCl:Tm²⁺,...

journal article 2019

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Functionalizing window coatings with luminescence centers by combinatorial sputtering of scatter-free amorphous SiAlON: Eu²⁺ thin film composition libraries

Merkx, E.P.J. (author), van Overbeek, S. (author), van der Kolk, E. (author)

SiAlON window coatings are applied on an industrial scale to achieve e.g. scratch-resistance and anti-reflection. Doping these SiAlONs with rare-earths adds luminescent functionality, which could be applied in photovoltaics. By using a combinatorial reactive sputtering approach, an amorphous thin film composition library with a Si:Al ratio...

journal article 2019

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Method for the Detailed Characterization of Cosputtered Inorganic Luminescent Material Libraries

Merkx, E.P.J. (author), van der Kolk, E. (author)

Understanding the behavior of combinatorially developed luminescent materials requires detailed characterization methods that have been lacking thus far. We developed a device for directly surveying the luminescent properties of thin-film libraries created through combinatorial gradient sputter deposition. Step-scan recorded excitation-,...

journal article 2018

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Rapid optimization of large-scale luminescent solar concentrators: evaluation for adoption in the built environment

Merkx, E.P.J. (author), ten Kate, O.M. (author), van der Kolk, E. (author)

The phenomenon of self-absorption is by far the largest influential factor in the eficiency of luminescent solar concentrators (LSCs), but also the most challenging one to capture computationally. In this work we present a model using a multiple-generation light transport (MGLT) approach to quantify light transport through single-layer...

journal article 2017

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Luminescent properties and energy level structure of CaZnOS:Eu2+

Budde, B (author), Luo, H. (author), Dorenbos, P. (author), van der Kolk, E. (author)

In this work it is shown that CaZnOS:Eu²⁺ has no Eu²⁺ emission even at low temperature. The observed and earlier reported red emission originates from a CaS:Eu²⁺ impurity phase. By means of washing the as-prepared samples with diluted nitride acid, we were able to remove the CaS impurity phase and study the...

journal article 2017

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Tm2+ luminescent materials for solar radiation conversion devices

Van der Kolk, E. (author)

A solar radiation conversion device is described that comprises a luminescent Tm 2+ inorganic material for converting solar radiation of at least part of the UV and/or visible and/or infra red solar spectrum into infrared solar radiation, preferably said infrared solar radiation having a wavelength of around 1138 nm; and, a photovoltaic device...

patent 2015

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Quantifying self-absorption losses in luminescent solar concentrators

Ten Kate, O.M. (author), Hooning, K.M. (author), Van der Kolk, E. (author)

Analytical equations quantifying self-absorption losses in circular luminescent solar concentrators (LSCs) are presented that can easily be solved numerically by commercial math software packages. With the quantum efficiency, the absorption and emission spectra of a luminescent material, the LSC dimensions, and the refractive index as the only...

journal article 2014

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Efficiency enhancement calculations of state-of-the-art solar cells by luminescent layers with spectral shifting, quantum cutting, and quantum tripling function

Ten Kate, O.M. (author), De Jong, M. (author), Hintzen, H.T. (author), Van der Kolk, E. (author)

Solar cells of which the efficiency is not limited by the Shockley-Queisser limit can be obtained by integrating a luminescent spectral conversion layer into the cell structure. We have calculated the maximum efficiency of state-of-the-art c-Si, pc-Si, a-Si, CdTe, GaAs, CIS, CIGS, CGS, GaSb, and Ge solar cells with and without an integrated...

journal article 2013

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Luminescent solar concentrator and solar device comprising such lumninescent solar concentrator

Van der Kolk, E. (author), Lammerse, D.B.B. (author)

patent 2012