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Author Mangnus, M.J.J.; de Wit, J.W.; Vonk, S.J.W.; Geuchies, J.J.; Albrecht, W.; Bals, S.; Houtepen, A.J.; Rabouw, F.T. url  doi
openurl 
  Title High-throughput characterization of single-quantum-dot emission spectra and spectral diffusion by multiparticle spectroscopy Type A1 Journal article
  Year (down) 2023 Publication ACS Photonics Abbreviated Journal  
  Volume 10 Issue 8 Pages 2688-2698  
  Keywords A1 Journal article; Engineering sciences. Technology; Electron microscopy for materials research (EMAT)  
  Abstract In recent years, quantum dots (QDs) have emerged as bright,color-tunablelight sources for various applications such as light-emitting devices,lasing, and bioimaging. One important next step to advance their applicabilityis to reduce particle-to-particle variations of the emission propertiesas well as fluctuations of a single QD's emission spectrum,also known as spectral diffusion (SD). Characterizing SD is typicallyinefficient as it requires time-consuming measurements at the single-particlelevel. Here, however, we demonstrate multiparticle spectroscopy (MPS)as a high-throughput method to acquire statistically relevant informationabout both fluctuations at the single-particle level and variationsat the level of a synthesis batch. In MPS, we simultaneously measureemission spectra of many (20-100) QDs with a high time resolution.We obtain statistics on single-particle emission line broadening fora batch of traditional CdSe-based core-shell QDs and a batchof the less toxic InP-based core-shell QDs. The CdSe-basedQDs show significantly narrower homogeneous line widths, less SD,and less inhomogeneous broadening than the InP-based QDs. The timescales of SD are longer in the InP-based QDs than in the CdSe-basedQDs. Based on the distributions and correlations in single-particleproperties, we discuss the possible origins of line-width broadeningof the two types of QDs. Our experiments pave the way to large-scale,high-throughput characterization of single-QD emission propertiesand will ultimately contribute to facilitating rational design offuture QD structures.  
  Address  
  Corporate Author Thesis  
  Publisher Place of Publication Editor  
  Language Wos 001009443500001 Publication Date 2023-06-18  
  Series Editor Series Title Abbreviated Series Title  
  Series Volume Series Issue Edition  
  ISSN 2330-4022 ISBN Additional Links UA library record; WoS full record; WoS citing articles  
  Impact Factor 7 Times cited 1 Open Access OpenAccess  
  Notes This work was supported by The Netherlands Center for Multiscale Catalytic Energy Conversion (MCEC), an NWO Gravitation Programme funded by the Ministry of Education, Culture and Science of the government of The Netherlands. The electron microscopy experiments at EMAT were supported by the European Commission (EUSMI grant E210100474). Approved Most recent IF: 7; 2023 IF: 6.756  
  Call Number UA @ admin @ c:irua:197337 Serial 8879  
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Author Kirkwood, N.; De Backer, A.; Altantzis, T.; Winckelmans, N.; Longo, A.; Antolinez, F.V.; Rabouw, F.T.; De Trizio, L.; Geuchies, J.J.; Mulder, J.T.; Renaud, N.; Bals, S.; Manna, L.; Houtepen, A.J. url  doi
openurl 
  Title Locating and controlling the Zn content in In(Zn)P quantum dots Type A1 Journal article
  Year (down) 2019 Publication Chemistry of materials Abbreviated Journal Chem Mater  
  Volume 32 Issue 32 Pages 557-565  
  Keywords A1 Journal article; Electron microscopy for materials research (EMAT)  
  Abstract Zinc is routinely employed in the synthesis of InP quantum dots (QDs) to improve the photoluminescence efficiency and carrier mobility of the resulting In(Zn)P alloy nanostructures. The exact location of Zn in the final structures and the mechanism by which it enhances the optoelectronic properties of the QDs is debated. We use synchrotron X-ray absorbance spectroscopy to show that the majority of Zn in In(Zn)P QDs is located at their surface as Zn-carboxylates. However, a small amount of Zn is present inside the bulk of the QDs with the consequent contraction of their lattice, as confirmed by combining high resolution high-angle annular dark-field imaging scanning transmission electron microscopy (HAADF-STEM) with statistical parameter estimation theory. We further demonstrate that the Zn content and its incorporation into the QDs can be tuned by the ligation of commonly employed Zn carboxylate precursors: the use of highly reactive Zn-acetate leads to the formation of undesired Zn3P2 and the final nanostructures being characterized by broad optical features, whereas Zn-carboxylates with longer carbon chains lead to InP crystals with much lower zinc content and narrow optical features. These results can explain the differences between structural and optical properties of In(Zn)P samples reported across the literature, and provide a rational method to tune the amount of Zn in InP nanocrystals and to drive the incorporation of Zn either as surface Zn-carboxylate, as a substitutional dopant inside the InP crystal lattice, or even predominantly as Zn3P2.  
  Address  
  Corporate Author Thesis  
  Publisher Place of Publication Editor  
  Language Wos 000507721600056 Publication Date 2019-12-13  
  Series Editor Series Title Abbreviated Series Title  
  Series Volume Series Issue Edition  
  ISSN 0897-4756 ISBN Additional Links UA library record; WoS full record; WoS citing articles  
  Impact Factor 9.466 Times cited 39 Open Access OpenAccess  
  Notes A.J.H. acknowledges support from the European Research Council Horizon 2020 ERC Grant Agreement No. 678004 (Doping on Demand). This research is supported by the Dutch Technology Foundation TTW, which is part of The Netherlands Organization for Scientific Research (NWO), and which is partly funded by Ministry of Economic Affairs. SB acknowledges funding from the European Research Council (grant 815128 REALNANO). The authors gratefully acknowledge funding from the Research Foundation Flanders (FWO, Belgium) through project funding G.0381.16N and a postdoctoral grant to A.D.B. AJH, LM and JM acknowledge support from the H2020 Collaborative Project TEQ (Grant No. 766900).; sygma Approved Most recent IF: 9.466  
  Call Number EMAT @ emat @c:irua:165234 Serial 5438  
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Author van der Burgt, J.S.; Geuchies, J.J.; van der Meer, B.; Vanrompay, H.; Zanaga, D.; Zhang, Y.; Albrecht, W.; Petukhov, A.V.; Filion, L.; Bals, S.; Swart, I.; Vanmaekelbergh, D. url  doi
openurl 
  Title Cuboidal supraparticles self-assembled from cubic CsPbBr3 perovskite nanocrystals Type A1 Journal article
  Year (down) 2018 Publication The journal of physical chemistry: C : nanomaterials and interfaces Abbreviated Journal J Phys Chem C  
  Volume 122 Issue 122 Pages 15706-15712  
  Keywords A1 Journal article; Engineering sciences. Technology; Electron microscopy for materials research (EMAT)  
  Abstract Colloidal CsPbBr3 nanocrystals (NCs) have emerged as promising candidates for various opto-electronic applications, such as light-emitting diodes, photodetectors, and solar cells. Here, we report on the self-assembly of cubic NCs from an organic suspension into ordered cuboidal supraparticles (SPs) and their structural and optical properties. Upon increasing the NC concentration or by addition of a nonsolvent, the formation of the SPs occurs homogeneously in the suspension, as monitored by in situ X-ray scattering measurements. The three-dimensional structure of the SPs was resolved through high-angle annular dark-field scanning transmission electron microscopy and electron tomography. The NCs are atomically aligned but not connected. We characterize NC vacancies on superlattice positions both in the bulk and on the surface of the SPs. The occurrence of localized atomic-type NC vacancies-instead of delocalized ones-indicates that NC-NC attractions are important in the assembly, as we verify with Monte Carlo simulations. Even when assembled in SPs, the NCs show bright emission, with a red shift of about 30 meV compared to NCs in suspension.  
  Address  
  Corporate Author Thesis  
  Publisher Place of Publication Washington, D.C. Editor  
  Language Wos 000439003600071 Publication Date 2018-06-14  
  Series Editor Series Title Abbreviated Series Title  
  Series Volume Series Issue Edition  
  ISSN 1932-7447; 1932-7455 ISBN Additional Links UA library record; WoS full record; WoS citing articles  
  Impact Factor 4.536 Times cited 60 Open Access OpenAccess  
  Notes ; The authors thank Dr. Rajeev Dattani and Jacques Gorini from the ID02 beamline of the ESRF for their excellent assistance during the X-ray scattering experiments. We also thank Carlo van Overbeek, P. Tim Prins, and Federico Montanarella for their support during the synchrotron experiments. The authors gratefully acknowledge Prof. Dr. Alfons van Blaaderen for fruitful discussions. D.V. acknowledges funding from NWO-CW TOPPUNT “Superficial superstructures.” J.J.G. acknowledges the joint Debye and ESRF graduate programs for the financial support. H.V. gratefully acknowledges the financial support by the Flemish Fund for Scientific Research (FWO grant 1S32617NN). S.B. acknowledges the financial support from the European Research Council (ERC Starting grant # 335078-COLOURATOMS). Y.Z. acknowledges the financial support from the European Union's Horizon 2020 research and innovation program, under the Marie Sklodowska-Curie grant agreement #665501 through a FWO [PEGASUS]2 Marie Sklodowska-Curie fellowship (12U4917N). W.A. acknowledges the financial support from the European Research Council under the European Unions Seventh Framework Program (FP-2007-2013)/ERC Advanced grant agreement 291667 HierarSACol. ; ecas_Sara Approved Most recent IF: 4.536  
  Call Number UA @ lucian @ c:irua:153161UA @ admin @ c:irua:153161 Serial 5087  
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Author van der Stam, W.; Geuchies, J.J.; Altantzis, T.; van den Bos, K.H.W.; Meeldijk, J.D.; Van Aert, S.; Bals, S.; Vanmaekelbergh, D.; de Mello Donega, C. pdf  url
doi  openurl
  Title Highly Emissive Divalent-Ion-Doped Colloidal CsPb1–xMxBr3Perovskite Nanocrystals through Cation Exchange Type A1 Journal article
  Year (down) 2017 Publication Journal of the American Chemical Society Abbreviated Journal J Am Chem Soc  
  Volume 139 Issue 139 Pages 4087-4097  
  Keywords A1 Journal article; Electron microscopy for materials research (EMAT)  
  Abstract Colloidal CsPbX3 (X = Br, Cl, and I) perovskite nanocrystals (NCs) have emerged as promising phosphors and solar cell materials due to their remarkable optoelectronic properties. These properties can be tailored by not only controlling the size and shape of the NCs but also postsynthetic composition tuning through topotactic

anion exchange. In contrast, property control by cation exchange is still underdeveloped for colloidal CsPbX3 NCs. Here, we present a method that allows partial cation exchange in colloidal CsPbBr3 NCs, whereby Pb2+ is exchanged for several isovalent cations, resulting in doped CsPb1−xMxBr3 NCs (M= Sn2+, Cd2+, and Zn2+; 0 < x ≤ 0.1), with preservation of the original NC shape. The size of the parent NCs is also preserved in the product NCs, apart from a small (few

%) contraction of the unit cells upon incorporation of the guest cations. The partial Pb2+ for M2+ exchange leads to a blue-shift of the optical spectra, while maintaining the high photoluminescence quantum yields (>50%), sharp absorption features, and narrow emission of the parent CsPbBr3 NCs. The blue-shift in the optical spectra is attributed to the lattice contraction that accompanies the Pb2+ for M2+ cation exchange and is observed to scale linearly with the lattice contraction. This work opens up new possibilities to engineer the properties of halide perovskite NCs, which to date are demonstrated to be the only known

system where cation and anion exchange reactions can be sequentially combined while preserving the original NC shape, resulting in compositionally diverse perovskite NCs.
 
  Address  
  Corporate Author Thesis  
  Publisher Place of Publication Editor  
  Language Wos 000397477700027 Publication Date 2017-03-10  
  Series Editor Series Title Abbreviated Series Title  
  Series Volume Series Issue Edition  
  ISSN 0002-7863 ISBN Additional Links UA library record; WoS full record; WoS citing articles  
  Impact Factor 13.858 Times cited 535 Open Access OpenAccess  
  Notes W.v.d.S. and C.d.M.D. acknowledge financial support from the division of Chemical Sciences (CW) of The Netherlands Organization for Scientific Research (NWO) under grant number ECHO.712.012.001. J.J.G. and D.V. acknowledge financial support from the Debye Graduate program. S.B. acknowledges financial support from the European Research Council (ERC Starting Grant # 335078-COLOURATOMS). K.H.W.v.d.B., S.B., S.V.A. and T.A. acknowledge financial support from the Research Foundation Flanders (FWO, Belgium) through project fundings (G.0374.13N, G.0368.15N, G.0369.15N), a Ph.D. grant to K.H.W.v.d.B, and a postdoctoral research grant to T.A. (ROMEO:white; preprint:; postprint:restricted 12 months embargo; pdfversion:cannot); ECAS_Sara Approved Most recent IF: 13.858  
  Call Number EMAT @ emat @ c:irua:141754UA @ admin @ c:irua:141754 Serial 4482  
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Author Geuchies, J.J.; van Overbeek, C.; Evers, W.H.; Goris, B.; de Backer, A.; Gantapara, A.P.; Rabouw, F.T.; Hilhorst, J.; Peters, J.L.; Konovalov, O.; Petukhov, A.V.; Dijkstra, M.; Siebbeles, L.D.A.; van Aert, S.; Bals, S.; Vanmaekelbergh, D. url  doi
openurl 
  Title In situ study of the formation mechanism of two-dimensional superlattices from PbSe nanocrystals Type A1 Journal article
  Year (down) 2016 Publication Nature materials Abbreviated Journal Nat Mater  
  Volume 15 Issue 15 Pages 1248-1254  
  Keywords A1 Journal article; Electron microscopy for materials research (EMAT)  
  Abstract Oriented attachment of PbSe nanocubes can result in the formation of two-dimensional (2D) superstructures with long-range nanoscale and atomic order. This questions the applicability of classic models in which the superlattice grows by first forming a nucleus, followed by sequential irreversible attachment of nanocrystals, as one misaligned attachment would disrupt the 2D order beyond repair. Here, we demonstrate the formation mechanism of 2D PbSe superstructures with square geometry by using in situ grazing-incidence X-ray scattering (small angle and wide angle), ex situ electron microscopy, and Monte Carlo simulations. We observed nanocrystal adsorption at the liquid/gas interface, followed by the formation of a hexagonal nanocrystal monolayer. The hexagonal geometry transforms gradually through a pseudo-hexagonal phase into a phase with square order, driven by attractive interactions between the {100} planes perpendicular to the liquid substrate, which maximize facet-to-facet overlap. The nanocrystals then attach atomically via a necking process, resulting in 2D square superlattices.  
  Address Condensed Matter and Interfaces, Debye Institute for Nanomaterials Science, Utrecht University, 3584 CC Utrecht, The Netherlands  
  Corporate Author Thesis  
  Publisher Place of Publication Editor  
  Language English Wos 000389104400011 Publication Date 2016-09-05  
  Series Editor Series Title Abbreviated Series Title  
  Series Volume Series Issue Edition  
  ISSN 1476-1122 ISBN Additional Links UA library record; WoS full record; WoS citing articles  
  Impact Factor 39.737 Times cited 182 Open Access OpenAccess  
  Notes This research is part of the programme ‘Designing Dirac Carriers in semiconductor honeycomb superlattices (DDC13),’ which is supported by the Foundation for Fundamental Research on Matter (FOM), which is part of the Dutch Research Council (NWO). J.J.G. acknowledges funding from the Debye and ESRF Graduate Programs. The authors gratefully acknowledge funding from the Research Foundation Flanders (G.036915 G.037413 and funding of postdoctoral grants to B.G. and A.d.B). S.B. acknowledges the European Research Council, ERC grant No 335078—Colouratom. The authors gratefully acknowledge I. Swart and M. van Huis for fruitful discussions. We acknowledge funding from NWO-CW TOPPUNT ‘Superficial Superstructures’. The X-ray scattering measurements were performed at the ID10 beamline at ESRF under proposal numbers SC-4125 and SC-3786. The authors thank G. L. Destri and F. Zontone for their support during the experiments.; ECAS_Sara; (ROMEO:yellow; preprint:; postprint:restricted ; pdfversion:cannot); Approved Most recent IF: 39.737  
  Call Number EMAT @ emat @ c:irua:136165 Serial 4289  
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Author Boneschanscher, M.P.; Evers, W.H.; Geuchies, J.J.; Altantzis, T.; Goris, B.; Rabouw, F.T.; van Rossum, S.A.P.; van der Zant, H.S.J.; Siebbeles, L.D.A.; Van Tendeloo, G.; Swart, I.; Hilhorst, J.; Petukhov, A.V.; Bals, S.; Vanmaekelbergh, D.; pdf  url
doi  openurl
  Title Long-range orientation and atomic attachment of nanocrystals in 2D honeycomb superlattices Type A1 Journal article
  Year (down) 2014 Publication Science Abbreviated Journal Science  
  Volume 344 Issue 6190 Pages 1377-1380  
  Keywords A1 Journal article; Engineering sciences. Technology; Electron microscopy for materials research (EMAT)  
  Abstract Oriented attachment of synthetic semiconductor nanocrystals is emerging as a route for obtaining new semiconductors that can have Dirac-type electronic bands like graphene, but also strong spin-orbit coupling. The two-dimensional assembly geometry will require both atomic coherence and long-range periodicity of the superlattices. We show how the interfacial self-assembly and oriented attachment of nanocrystals results in two-dimensional (2D) metal chalcogenide semiconductors with a honeycomb superlattice. We present an extensive atomic and nanoscale characterization of these systems using direct imaging and wave scattering methods. The honeycomb superlattices are atomically coherent, and have an octahedral symmetry that is buckled; the nanocrystals occupy two parallel planes. Considerable necking and large-scale atomic motion occurred during the attachment process.  
  Address  
  Corporate Author Thesis  
  Publisher Place of Publication Washington, D.C. Editor  
  Language Wos 000337531700035 Publication Date 2014-05-30  
  Series Editor Series Title Abbreviated Series Title  
  Series Volume Series Issue Edition  
  ISSN 0036-8075;1095-9203; ISBN Additional Links UA library record; WoS full record; WoS citing articles  
  Impact Factor 37.205 Times cited 304 Open Access OpenAccess  
  Notes Fwo; 262348 Esmi; 246791 Countatoms; 335078 Colouratom; ECAS_Sara; (ROMEO:green; preprint:; postprint:can ; pdfversion:cannot); Approved Most recent IF: 37.205; 2014 IF: 33.611  
  Call Number UA @ lucian @ c:irua:117095 Serial 1840  
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Author Kalesaki, E.; Boneschanscher, M.P.; Geuchies, J.J.; Delerue, C.; Morais Smith, C.; Evers, W.H.; Allan, G.; Altantzis, T.; Bals, S.; Vanmaekelbergh, D. pdf  url
doi  openurl
  Title Preparation and study of 2-D semiconductors with Dirac type bands due to the honeycomb nanogeometry Type P1 Proceeding
  Year (down) 2014 Publication Proceedings of the Society of Photo-optical Instrumentation Engineers T2 – Proceedings of SPIE Abbreviated Journal  
  Volume 8981 Issue Pages 898107-898107  
  Keywords P1 Proceeding; Engineering sciences. Technology; Electron microscopy for materials research (EMAT)  
  Abstract The interest in 2-dimensional systems with a honeycomb lattice and related Dirac-­type electronic bands has exceeded the prototype graphene1. Currently, 2-­dimensional atomic2,3 and nanoscale4-­8 systems are extensively investigated in the search for materials with novel electronic properties that can be tailored by geometry. The immediate question that arises is how to fabricate 2-­D semiconductors that have a honeycomb nanogeometry, and as a consequence of that, display a Dirac-­type band structure? Here, we show that atomically coherent honeycomb superlattices of rocksalt (PbSe, PbTe) and zincblende (CdSe, CdTe) semiconductors can be obtained by nanocrystal self-­assembly and facet-­to-­facet atomic bonding, and subsequent cation exchange. We present a extended structural analysis of atomically coherent 2-­D honeycomb structures that were recently obtained with self-assembly and facet-­to-­facet bonding9. We show that this process may in principle lead to three different types of honeycomb structures, one with a graphene type-­, and two others with a silicene-­type structure. Using TEM, electron diffraction, STM and GISAXS it is convincingly shown that the structures are from the silicene-­type. In the second part of this work, we describe the electronic structure of graphene-­type and silicene type honeycomb semiconductors. We present the results of advanced electronic structure calculations using the sp3d5s* atomistic tight-­binding method10. For simplicity, we focus on semiconductors with a simple and single conduction band for the native bulk semiconductor. When the 3-­D geometry is changed into 2-­D honeycomb, a conduction band structure transformation to two types of Dirac cones, one for S-­ and one for P-­orbitals, is observed. The width of the bands depends on the honeycomb period and the coupling between the nanocrystals. Furthermore, there is a dispersionless P-­orbital band, which also forms a landmark of the honeycomb structure. The effects of considerable intrinsic spin-­orbit coupling are briefly considered. For heavy-­element compounds such as CdTe, strong intrinsic spin-­‐orbit coupling opens a non-­trivial gap at the P-­orbital Dirac point, leading to a quantum Spin Hall effect10-­12. Our work shows that well known semiconductor crystals, known for centuries, can lead to systems with entirely new electronic properties, by the simple action of nanogeometry. It can be foreseen that such structures will play a key role in future opto-­electronic applications, provided that they can be fabricated in a straightforward way.  
  Address  
  Corporate Author Thesis  
  Publisher Place of Publication Editor  
  Language Wos 000336040600004 Publication Date 2014-03-07  
  Series Editor Series Title Abbreviated Series Title  
  Series Volume Series Issue Edition  
  ISSN ISBN Additional Links UA library record; WoS full record; WoS citing articles  
  Impact Factor Times cited 2 Open Access OpenAccess  
  Notes This work has been supported by funding of the French National Research Agency [ANR, (ANR-­‐09-­‐BLAN-­‐0421-­‐01)], NWO and the Dutch organization FOM [Programs “Control over Functional Nanoparticle Solids” (FNPS) and “Designing Dirac Carriers in Semiconductors” Approved Most recent IF: NA  
  Call Number c:irua:131912 Serial 4039  
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