Kurajica Stanislav, Mandić Vilko, Panžić Ivana, Gaboardi Mattia, Mužina Katarina, Lozančić Ana, Šipušić Juraj, Munda Ivana Katarina, Višić Lucija, Blagojević Sanja Lučić, Gigli Lara, Plaisier Jasper Rikkert
Faculty of Chemical Engineering and Technology, University of Zagreb, Marulićev trg 20, 10000 Zagreb, Croatia.
Ruđer Bošković Institute, Bijenička Cesta 54, 10000 Zagreb, Croatia.
Nanomaterials (Basel). 2020 Dec 17;10(12):2537. doi: 10.3390/nano10122537.
Pure and doped vanadia (VO, VZrO, VCeO) samples were prepared by wet chemistry synthesis from vanadyl glycolate intermediate phase and tape casted into films. Combining in-operando grazing incidence synchrotron X-ray diffraction and Raman spectroscopy, we studied the structural evolution of the films under isothermal conditions. The setup allowed assessment of the thermochromic functionality with continuous monitoring of the monoclinic to tetragonal transition in pure and doped vanadia phases, responsible for the transmission and reflection of light in the infrared part of the solar spectrum. The materials characterisation by X-ray diffraction beamline (MCX) goniometer demonstrated ideal performance, combining flexible geometry, high resolution, and the potential to accommodate the multi-channel equipment for in-operando characterisation. This method proved viable for evaluating the relevant structural and physical, and thereof functional properties of these systems. We revealed that dopants reduce the transition temperature by 5 °C on average. The synthetic route of the films was held responsible for the observed phase separation. The more favourable behaviour of cerium-doped sample was attributed to cerium alkoxide behaviour. In addition, structural, microstructural, thermal, and spectroscopic characterisation on powder samples was performed to gain more insight into the development of the phases that are responsible for thermochromic features in a broader range of doping ratios. The influence of the dopants on the extent of the thermochromic transition (transmission to reflection hysteresis) was also evaluated using (micro) structural, thermal and spectroscopic methods of powder samples. Characterisations showed that zirconium doping in 2, 4, and 6 mol% significantly influenced the phase composition and morphology of the precursor. Vanadium oxides other than VO can easily crystallise; however, a thermal treatment regime that allowed crystallisation of VO as a single phase was established.
通过以乙醇酸氧钒中间相为原料的湿化学合成法制备了纯钒氧化物以及掺杂钒氧化物（VO、VZrO、VCeO）样品，并将其流延成膜。结合原位掠入射同步辐射X射线衍射和拉曼光谱，我们研究了薄膜在等温条件下的结构演变。该装置能够通过连续监测纯钒氧化物相和掺杂钒氧化物相中从单斜相到四方相的转变来评估热致变色功能，这种转变决定了太阳光谱红外部分的光透射和反射。通过X射线衍射光束线（MCX）测角仪进行的材料表征显示出理想的性能，它具有灵活的几何结构、高分辨率以及容纳多通道设备进行原位表征的潜力。该方法被证明对于评估这些体系的相关结构、物理及其功能特性是可行的。我们发现掺杂剂平均使转变温度降低了5℃。薄膜的合成路线被认为是导致观察到的相分离的原因。铈掺杂样品表现出更有利的行为归因于铈醇盐的行为。此外，还对粉末样品进行了结构、微观结构、热学和光谱表征，以更深入了解在更广泛的掺杂比例范围内对热致变色特性起作用的相的发展情况。还使用粉末样品的（微观）结构、热学和光谱方法评估了掺杂剂对热致变色转变程度（透射 - 反射滞后）的影响。表征结果表明，2%、4%和6%摩尔比的锆掺杂显著影响了前驱体的相组成和形态。除VO之外的钒氧化物很容易结晶；然而，建立了一种能使VO以单相形式结晶的热处理制度。
