References of "Spronck, Gilles"
     in
Bookmark and Share    
Full Text
See detailLead-free double perovskite materials for photovoltaic application
Daem, Nathan ULiege; Dewalque, Jennifer ULiege; Spronck, Gilles ULiege et al

Poster (2019, May 13)

This work consists in studying the implementation of double perovskite materials in the form of thin film and showing the effect of the deposition conditions on the structural properties (uniformity ... [more ▼]

This work consists in studying the implementation of double perovskite materials in the form of thin film and showing the effect of the deposition conditions on the structural properties (uniformity, coverage rate, roughness, thickness, crystallinity, crystallite size) and on the optoelectronic properties (light absorption, electron-hole pair generation efficiency, charge diffusion length, recombination...). Before considering ultrasonic spray pyrolysis deposition, preliminary spin-coating tests are ongoing in order to verify the formation of Cs2AgBiBr6 phase according to the protocol reported by Greul et al. (J. Mater Chem A (2017), 19972-19981). The effect of precursors concentration, thermal post-treatment (hot plate/oven, temperature/duration), antisolvent dripping, relative humidity - which are reported as critical parameters for the preparation of high efficiency lead halides perovskite solar cells - on the layer morphology have been studied. The (micro)structural properties of the layers (uniformity, coverage rate, crystallite size, crystalline phase) have been characterized by scanning electron microscopy and X-ray diffraction. To improve charge collection within the lead-free double perovskite photoactive material, we have also investigated a mesoporous TiO2 network as an electron collecting material filled by Cs2AgBiBr6. Efficiencies of 1.7 % have been reached for our best PV cells which are very promising results. [less ▲]

Detailed reference viewed: 98 (10 ULiège)
Full Text
See detailOpal-like CH3NH3PbI3 perovskite solar cells : effect of the 3D structuration on the conversion efficiency
Dewalque, Jennifer ULiege; Daem, Nathan ULiege; Spronck, Gilles ULiege et al

Poster (2019, May 13)

In this work, the 3D structuration of perovskite films is studied in order to highlight the effect of a periodic porous structure on the optical properties of the films (light harvesting, optical ... [more ▼]

In this work, the 3D structuration of perovskite films is studied in order to highlight the effect of a periodic porous structure on the optical properties of the films (light harvesting, optical coloration, semi-transparency…) and on the PV efficiency, in comparison with dense perovskite films usually used in planar solar cells configuration. The opal-like perovskite scaffold is obtained from templating fabrication method, with polystyrene beads as structuring agent. Five PS bead diameters are studied: 300 nm, 540 nm, 810 nm, 1.0 µm and 2.1 µm, to highlight the effect of the PS bead diameter on the optical properties of the films and on the PV efficiency. PbI2/CH3NH3I 0.7M in DMSO leads to the most covering, homogeneous and overlayer-free porous films. The PV efficiency of the corresponding cells increases with the bead diameter. A significant improvement in the PV conversion efficiency is observed thanks to the 3D structuration compared to a dense reference, due to the improvement of charge separation at the Spiro-OMeTAD/perovskite interface and thus to the reduction of charge recombination. In addition, CH3NH3PbI3 porous films prepared with 810 nm, 1000 nm and 2100 nm PS bead diameter respectively, are coloured, which is very interesting for building-integrated applications (BIPV). [less ▲]

Detailed reference viewed: 50 (7 ULiège)
See detailDesign of monodisperse polystyrene/polyacrylonitrile core-shell particles used as templating agents and source of carbon
Thangaraj, Vidhyadevi ULiege; Schrijnemakers, Audrey ULiege; Dewalque, Jennifer ULiege et al

Poster (2018, October 03)

In the present work, we synthesized Polystyrene (PS) and Polystyrene/polyacrylonitrile (PS/PAN) core shell particles by surfactant-free emulsion polymerization and characterized them by DLS and TEM. After ... [more ▼]

In the present work, we synthesized Polystyrene (PS) and Polystyrene/polyacrylonitrile (PS/PAN) core shell particles by surfactant-free emulsion polymerization and characterized them by DLS and TEM. After deposition of the PS/PAN particles on a surface, a TiCl4 solution was infiltrated in the interstices before thermal treatment. The carbonization of the PS core and the PAN shell led to voids and carbon in the inorganic layer, respectively. This paved the way to well-organized carbon coated porous TiO2 layers of interest in the field of electronics. [less ▲]

Detailed reference viewed: 53 (12 ULiège)
Full Text
See detailSpray coating as scalable deposition technique of TiO2 blocking layer to boost the perovskite solar cell performances
Schrijnemakers, Audrey ULiege; Dewalque, Jennifer ULiege; Spronck, Gilles ULiege et al

Poster (2018, February 28)

To achieve high efficiency, the blocking layer (BL) is of critical importance in perovskite solar cells. Indeed, substrate has to be covered by a dense TiO2 film to prevent short circuits in the final PV ... [more ▼]

To achieve high efficiency, the blocking layer (BL) is of critical importance in perovskite solar cells. Indeed, substrate has to be covered by a dense TiO2 film to prevent short circuits in the final PV cell. In this study, we compare the spin coating (SC) technique - commonly used for the TiO2 blocking layer deposition in solid-state methylammonium lead triiodide perovskite (MaPbI3)-based solar cells - with ultrasonic spray pyrolysis (USP). Ultrasonic spray coating is a promising non-vacuum pathway to manufacture blocking layer that can be implemented from laboratory to industrial scale. The BL microstructure is characterized by scanning electron microscopy (SEM) and X-Ray diffraction (XRD). Although both deposition techniques lead to similar coating thickness and structure, the cyclic voltammetry measurements highlight the higher blocking capability of the ultrasonic spray pyrolysis BL. The BLs were tested in complete solar cell devices. Performance of perovskite solar cells is discussed and related to the morphology and the conductivity of the TiO2 blocking layers. [less ▲]

Detailed reference viewed: 53 (16 ULiège)
Full Text
See detailOpal-like photoanodes with photonic effects in macroporous perovskite solar cells
Dewalque, Jennifer ULiege; Baron, Damien ULiege; Spronck, Gilles ULiege et al

Poster (2018, February 28)

Organic-inorganic metal halide perovskite compounds, used either in mesoscopic or planar solar cells architectures, have allowed preparing highly efficient solid-state devices (>20%). In mesoscopic solar ... [more ▼]

Organic-inorganic metal halide perovskite compounds, used either in mesoscopic or planar solar cells architectures, have allowed preparing highly efficient solid-state devices (>20%). In mesoscopic solar cells, a mesoporous TiO2 scaffold is incorporated into the cells. However, because of the small pore size compared to the wavelengths of visible light, the scaffold barely scatters light. In this work, we propose to design periodically structured TiO2 scaffold from colloidal crystal templating fabrication method. Polystyrene beads with diameters comparable to visible light wavelengths are used as structuring agent. The resulting opal-like photonic structure will strongly interact with light and increase light harvesting. The photoanode microstructure is characterized by scanning electron microscopy (SEM) and X-Ray diffraction (XRD). In parallel, light interaction is modeled in order to find the best compromise in terms of photonic architecture. Sunlight absorption by the solar cells is presented and discussed with dependency of pore sizes and number of opal-like layers. [less ▲]

Detailed reference viewed: 111 (34 ULiège)
Full Text
See detailInverse opal photoanodes: preparation and optical properties
Dewalque, Jennifer ULiege; Spronck, Gilles ULiege; Baron, Damien ULiege et al

Conference (2017, March 01)

Perovskite compounds, used either in mesoscopic or planar solar cells, have allowed preparing highly efficient solid-state devices (>20%). In this study, we propose to design photoanodes with photonic ... [more ▼]

Perovskite compounds, used either in mesoscopic or planar solar cells, have allowed preparing highly efficient solid-state devices (>20%). In this study, we propose to design photoanodes with photonic structure in order to modulate light interaction. The periodic structure of porosity could add specific optical properties likely to increase light harvesting and reduce reflexion losses. Besides, current efficiencies reported for mesoscopic perovskite solar cells using an inorganic porous scaffold are slightly lower than those reported for planar perovskite cells mainly due to issues in perovskite infiltration. The control of the porous network architecture in terms of pore organization, size and connectivity could overcome this limitation. TiO2/perovskite and perovskite-only photoanodes with an inverse opal porous structure are prepared from templating techniques, using polystyrene beads as structuring agent. The photoanode microstructure is further characterized by scanning electron microscopy (SEM) and X-Ray diffraction (XRD). In parallel, light interaction is modeled in order to find the best compromise in terms of photonic architecture (pore size, organization, thickness…). [less ▲]

Detailed reference viewed: 81 (22 ULiège)
Full Text
Peer Reviewed
See detailComparison of Indium Tin Oxide and Indium Tungsten Oxide as Transparent Conductive Substrates for WO3-Based Electrochromic Devices
Maho, Anthony ULiege; Nicolay, Sylvain; Manceriu, Laura ULiege et al

in Journal of the Electrochemical Society (2017), 164(2), 25-31

Detailed reference viewed: 66 (28 ULiège)
Peer Reviewed
See detailSurfactant-assisted USP deposition of WO3 electrochromic thin films on various TCO-glass substrates
Maho, Anthony ULiege; Nicolay, Sylvain; Manceriu, Laura ULiege et al

Conference (2016, August 31)

Detailed reference viewed: 46 (9 ULiège)
Full Text
See detailInnovative semiconducting oxide materials reducing the energy footprint of buildings
Dewalque, Jennifer ULiege; Maho, Anthony ULiege; Spronck, Gilles ULiege et al

Conference (2015, October 26)

In the current energy context, many efforts are devoted to the reduction of the energy footprint of buildings. To meet this challenge, the LCIS-GREENMAT laboratory developes a front edge research in the ... [more ▼]

In the current energy context, many efforts are devoted to the reduction of the energy footprint of buildings. To meet this challenge, the LCIS-GREENMAT laboratory developes a front edge research in the field of advanced materials associated to energy and environment, including structured materials for dye-sensitized solar cells (DSSCs) and electrochromic coatings. DSSCs have been reported by O’Regan and Grätzel in the early nineties as a very promising alternative to conventional photovoltaic silicon devices. Main benefits of these cells are their low cost as well as their mild manufacturing process. In most of the specific literature, DSSCs are made of TiO2 films prepared by doctor-blade or screen-printing of anatase nanoparticles paste. However, due to the random organization of the nanoparticles, pore accessibility by the dye and electrolyte could be incomplete. Moreover, some anatase crystallites could suffer from a lack of connectivity, leading to electron transfer issues. The strategy adopted by our group to improve photovoltaic efficiencies involves a templating-assisted process to prepare highly porous layers with well-ordered and accessible pores as well as improved crystallites connectivity. This talk especially focuses on the templating-assisted synthesis of TiO2 and ZnO semiconducting layers used as photoelectrode in DSSCs. Due to the surface area improvement as well as the perfect control of the pore organization and the pore size, the templating strategy is an effective solution to maximize the adsorption of active dye and the electrolyte infiltration inside the porous network. Besides, in the last few years, there has been increasing interest in electrochromic glazing due to its potential use as an energy-efficient component for buildings, as it could reduce considerably their CO2 emission by decreasing their energy consumption up to 30%. The crucial issues of such devices are the durability, the coloration efficiency and the reversibility upon coloration and bleaching of the electrochromic layers. In order to improve the performances of those electrochromic films, we have investigated a surfactant-assisted deposition process for WO3 layer and the insertion of lithium in the NiO layer. All films have been deposited on FTO glass substrates by ultrasonic spray pyrolysis (USP), which is a low-cost alternative to industrial vacuum processes for manufacturing high quality thin films. The presence of lithium ions in nickel oxide films has shown improved coloration efficiency compared to the undoped films. The higher active surface of surfactant-assisted tungsten oxide films has led to higher reversibility and coloration contrast. [less ▲]

Detailed reference viewed: 75 (21 ULiège)
Full Text
Peer Reviewed
See detailElucidating the opto-electrical properties of solid and hollow titania scattering layers for improvement of dye-sensitized solar cells
Thalluri, Venkata Visveswara Gopala Kris; Henrist, Catherine ULiege; Spronck, Gilles ULiege et al

in Thin Solid Films (2015)

The light scattering method has been adapted in dye-sensitized solar cells (DSCs) for optical absorption enhancement. In DSC's, particle-size of TiO2 should be inline with the scattering wavelength range ... [more ▼]

The light scattering method has been adapted in dye-sensitized solar cells (DSCs) for optical absorption enhancement. In DSC's, particle-size of TiO2 should be inline with the scattering wavelength range. Scattering particles can be used either by forming a bilayer structure with TiO2 nanocrystalline film or into the bulk of TiO2 nanocrystalline film. For improving the DSCs performances these scattering layers aim to refract/reflect the incident light by extending the traveling distance of UV-Visible/near-IR light within the dye-sensitized TiO2 nanocrystalline film. In this work, the scattering layers with two different particle-sizes (~200 nm-solid and ~400 nm-hollow) were deposited as an additional layer on the top of dye-sensitized TiO2 nanocrystalline film and the morphological properties were studied. By using various opto-electrical characterization techniques, the influence of these scattering layers for two different classes of DSCs prepared from N3 (UV-Vis) and SQ2 (near-IR) dyes were investigated. [less ▲]

Detailed reference viewed: 63 (25 ULiège)
Full Text
Peer Reviewed
See detailImproved coloration contrast and electrochromic efficiency of tungsten oxide films thanks to a surfactant-assisted ultrasonic spray pyrolysis process
Denayer, Jessica ULiege; Aubry, Philippe; Bister, Geoffroy et al

in Solar Energy Materials and Solar Cells (2014), 130

Detailed reference viewed: 112 (71 ULiège)
Full Text
See detailStudies on the Influence of Different Grain-sized Titania Scattering Layers for Dye Sensitized Solar Cells
Thalluri, Venkata Visveswara Gopala Kris ULiege; Henrist, Catherine ULiege; Vertruyen, Bénédicte ULiege et al

Poster (2013, July)

The efficiencies of dye sensitized solar cells (DSCs) are boosted up to 12% by NIR light harvesting dyes and with the usage of scattering layer in the device preparation.The importance of Titania ... [more ▼]

The efficiencies of dye sensitized solar cells (DSCs) are boosted up to 12% by NIR light harvesting dyes and with the usage of scattering layer in the device preparation.The importance of Titania scattering layers was studied as a part of this work. These scattering layers were prepared from two different grain-sizes (100 nm & 500 nm) for SQ2-NIR and N3-UV/Vis DSCs. The 100 nm grain-sized Titania paste was commercially supplied and 500 nm grain-sized Titania paste was prepared according to literature. The morphological and structural properties of these bigger grain-sized Titania layers were deliberated by using and Scanning Electron Microscope (SEM) and X-Ray diffraction (XRD) measurements. The influence of these bigger grain-sized Titania scattering layers in SQ2-NIR and N3-UV/Vis DSCs were expounded by using various electro-optical characterization techniques such as light I-V, electrochemical impedance spectroscopy (EIS) shown in Figure 1 and external quantum efficiency (EQE) measurements. The importance of understanding the influence of these bigger grain-sized scattering Titania layers could pave a way for future design and optimizing of DSCs for increasing the amount of light harvesting. [less ▲]

Detailed reference viewed: 58 (20 ULiège)
Full Text
Peer Reviewed
See detailTiO2 mesoporous thin films studied by Atmospheric Ellipsometric Porosimetry: A case of contamination
Dubreuil, Olivier ULiege; Dewalque, Jennifer ULiege; Chene, Grégoire ULiege et al

in Microporous and Mesoporous Materials (2011), 147

Anatase mesoporous TiO2 thin films are frequently prepared by surfactant templating to control porosity development and Atmospheric Ellipsometric Porosimetry is a reliable and fast technique allowing the ... [more ▼]

Anatase mesoporous TiO2 thin films are frequently prepared by surfactant templating to control porosity development and Atmospheric Ellipsometric Porosimetry is a reliable and fast technique allowing the determination of the porosity of such films. After prolonged exposition to high-vacuum (6×10-6 mbar), the films porosity exhibits a degraded behavior during porosimetric measurements, indicating a vacuum-induced modification. The main effect resulting from such exposition to high-vacuum is a wet- tability modification of the films, resulting in an increase of the hydrophobic character of the TiO2 surface. This evolution induces non-correct results in porosimetric measurements due to the fact that the contact angle parameter needed to calculate the pore size distribution is highly different from the reference films. A surface contamination explains such modifications and a restoration of the films is obtained by using ultraviolet treatment. [less ▲]

Detailed reference viewed: 149 (44 ULiège)