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Glass and glass-ceramic materials containing photoactive and magnetic crystalline phases were prepared from Fe2O3 and Bi2O3 using the conventional melt method. All samples were characterized in terms of formed phases, morphological analyses, optical properties, and magnetic properties. Formation of the photoactive tetragonal β- and body-centered cubic γ-Bi2O3 phases along with the magnetic BiFeO3 and Fe3O4 phases was revealed. However, the crystalline structure relied on the composition and the applied heat-treatment time. β-/γ-Bi2O3 transformation could be controlled by the heat-treatment time. The samples exhibited variable magnetic properties depending on their composition. All of the samples showed excellent absorbance in visible light with an optical band gap of 1.90–2.22 eV, making them ideal for solar-light-driven photocatalysis. The best performance was recorded for the sample containing equal amounts of Fe2O3 and Bi2O3 due to the formation of γ-Bi2O3/BiFeO3 heterojunction in this sample.

In this study, nanoscale crednerite (CuMnO

SUMMARY Crednerite glass‐ceramic material (CuMnO2) has been investigated for the first time as a hydrogen storage candidate. The average gravimetric capacity is about 16 g H2/kg and about 50 g H2/kg of CuMnO2 at 473 and 573 K respectively under a pressure up to 20 bars. The hydrogen adsorbed capacity (weight percent) of CuMnO2 increased with increasing temperature. The material doesn't release hydrogen during desorption cycle revealing storage of hydrogen in the prepared material. X‐ray diffraction patterns reveal a structure corresponding to Cu2O, CuMnO2, and traces of CuO and SiO2 phases. X‐ray diffraction patterns exhibit a reduction of copper ions to copper metal beside cristobalite and traces from manganese oxide phase after exposing to H2 at 80 and 573 K. This reduction of Cu ions into Cu metal may explain the irreversibility of hydrogen adsorption process. Thermal stability detected by differential scanning calorimetry and thermal gravimetric analysis shows decomposition temperature up to ~473 K followed by gain of weight till 1173 K then another decomposition till 1273 K. Copyright © 2013 John Wiley & Sons, Ltd.

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