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The (111)-layered perovskite materials Ba5 Ta4 O15 , Ba5 Ta2 Nb2 O15 and Ba5 Nb4 O15 are prepared with nanofiber morphology via electrospinning for the first time. The nanofibers are built up from small single crystals, with up to several micrometers length even after calcination. The formation mechanism is investigated in detail, revealing an intermediate formation of amorphous barium carbonate strengthening the nanofiber morphology for high temperature treatment. All nanofiber compounds are able to generate hydrogen without any co-catalyst in photocatalytic reformation of methanol. After photodeposition of Rh-Cr2 O3 co-catalysts, the nanofibers show better activity in overall water splitting compared to sol-gel-derived powders.

In the present study, the dissolution of softwood fibers and fabrication of all-cellulose composites was investigated using aqueous tetraethylammonium hydroxide solution (TEAOH, 35 wt%) at room temperature. The bulk of the cellulose fibers were instantly dissolved when mixed with the solvent, and suspensions up to 3wt% were fabricated with ease. During the dissolution, a few remaining larger fiber flocks were fully dissolved within 3 h of mixing at room temperature. TEAOH was further studied in the production of all-cellulose composites by solvent welding (partial dissolution) of cellulose fiber sheets. Tensile strength of the original cellulose sheet increased from 3.3 to 55.0 MPa only after 30 s of room-temperature solvent welding, and an increase of over 23-fold (up to 76.7 MPa) was obtained by high-pressure-aided hot-pressing of the partially dissolved sheets before drying. The demonstrated fabrication of allcellulose composites yielded many benefits in comparison to the current dissolution systems,