The incorporation of selenocianated-based redox couple in a polymer electrolyte for dye-sensitized solar cells is reported for the first time. The pseudohalogen redox mediator was integrated in two kinds of acrylic/methacrylic membranes prepared by photocopolymerization of multifunctional monomers. Before activation, the obtained membranes were transparent, self-standing and flexible, and the physicochemical characterizations of the films showed the formation of highly crosslinked architectures. Membranes were activated by swelling in an optimized solution containing the SeCN–/(SeCN)2 redox mediator with 4-tert-butylpyridine in acetonitrile, and the electrochemical behavior of the electrolytes revealed fast charge transfer kinetics. The photovoltaic performances of quasi-solid dye-sensitized solar cells were evaluated and compared with the results of the liquid counterpart, showing promising photoharvesting properties. No diminution in photoconversion efficiencies was evidenced in the comparison between solid and liquid cells, demonstrating an optimal kinetics of the redox species in the polymer cage, associated with a noteworthy increase in device durability, as demonstrated by aging tests. In addition, the in situ photopolymerization in the presence of the redox mediator is presented with outstanding results: this process, hardly feasible for the traditional I–/I3 – couple (inhibitor of radical polymerization processes), enables at the same time the creation of an excellent electrode/electrolyte interface and the sealing of the device.

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Manganese oxides (MnO) are considered as a promising catalyst alternative to platinum in fuel cell applications. In fact, a proper catalyst is needed in order to facilitate the oxygen reduction reaction (ORR) at the cathode, and platinum is considered the best material due to its low overpotential for this reaction. Contrary to platinum, MnO is inexpensive, environmentally friendly and can be shaped into several nanostructures; furthermore, most of them show significant electro-catalytic performance. Several strategies have been carried out in order to increase their efficiency, by preparing light and high-surface area materials. In this framework, nanofibres are among the most promising nanostructures that can be used for this purpose. In this work, a study of the thermal, morphological and catalytic behavior of MnO nanofibres obtained through the electrospinning technique is proposed. Emphasis is given to the thermal evolution of the precursors, proposing a possible crystallization mechanism of the different manganese oxides obtained. It turns out that manganese oxide nanofibres exhibit good catalytic performance for the ORR, comparable to those obtained by using Pt-based catalysts.