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Quantum dot (QD)-sensitized solar cells (QDSSCs) are expected to achieve higher energy conversion efficiency than traditional single-junction silicon solar cells due to the unique properties of QDs. An inverse opal (IO)-TiO2 (IO-TiO2) electrode is useful for QDSSCs because of its three-dimensional (3D) periodic nanostructures and better electrolyte penetration compared to the normal nanoparticles (NPs)-TiO2 (NPs-TiO2) electrode. We find that the open-circuit voltages Voc of the QDSSCs with IO-TiO2 electrodes are higher than those of QDSSCs with NPs-TiO2 electrodes. One important strategy for enhancing photovoltaic conversion efficiency of QDSSCs with IO-TiO2 electrodes is surface passivation of photoanodes using wide-bandgap semiconducting materials. In this study, we have proposed surface passivation on IO-TiO2 with ZnS coating before QD deposition. The efficiency of QDSSCs with IO-TiO2 electrodes is largely improved (from 0.74% to 1.33%) because of the enhancements of Voc (from 0.65 V to 0.74 V) and fill factor (FF) (from 0.37 to 0.63). This result indicates that ZnS passivation can reduce the interfacial recombination at the IO-TiO2/QDs and IO-TiO2/electrolyte interfaces, for which two possible explanations can be considered. One is the decrease of recombination at IO-TiO2/electrolyte interfaces, and the other one is the reduction of the back-electron injection from the TiO2 electrode to QDs. All of the above results are effective for improving the photovoltaic properties of QDSSCs. [ABSTRACT FROM AUTHOR]

• Molten salt electrolysis is a promising method of preparing rare-earth Yb alloys. • Dissolution of Yb 2 O 3 in a eutectic LiF–YbF 3 system is critical. • Isothermal saturation was used to study the solubility of Yb 2 O 3 in the molten salt. • Quantum chemical calculations and further experimental methods were also used. • The main ionic forms in the system were Li+, F–, and YbF 4 –. The dissolution of Yb 2 O 3 in eutectic LiF–YbF 3 systems and resulting structural changes in the systems are key factors ensuring efficient electrolysis during the synthesis of rare-earth Yb alloys. In this study, isothermal saturation was used to determine the solubilities of Yb 2 O 3 in eutectic LiF and LiF–YbF 3 molten salts. The interactions between the components of the LiF–YbF 3 –Yb 2 O 3 system were studied using a combination of quantum chemical calculations, thermodynamic analysis, and experimental verification. The structural evolution of the system was analyzed using high-temperature Raman spectroscopy and ab initio molecular dynamics simulations during the integration of Yb 2 O 3 into a eutectic LiF–YbF 3 molten salt. The main phases in the LiF–(21 mol.%)YbF 3 system saturated with Yb 2 O 3 consisted of LiF, LiYbF 4 , and a minimal amount of YbOF and its derivatives. Yb 2 O 3 did not alter the main structure of the LiF–LiYbF 4 system, and Li+, F −, and YbF 4 − were the main ionic forms in the system. The Yb–F bond in YbOF was less stable than the Yb–O bond, and YbOF easily dissociated into YbO+and F −. [Display omitted] The dissolution behavior of Yb 2 O 3 in LiF-YbF 3 eutectic system was studied by a variety of experiments and simulation methods. The research found that the main phases in the LiF–(21 mol.%)YbF 3 system saturated with Yb 2 O 3 consisted of LiF, LiYbF 4 , and a minimal amount of YbOF and its derivatives. [ABSTRACT FROM AUTHOR]