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This work reports a novel approach for the synthesis of FeCo alloy nanoparticles (NPs) embedded in the N,P‐codoped carbon coated nitrogen‐doped carbon nanotubes (NPC/FeCo@NCNTs). Specifically, the synthesis of NCNT is achieved by the calcination of graphene oxide‐coated polystyrene spheres with Fe3+, Co2+ and melamine adsorbed, during which graphene oxide is transformed into carbon nanotubes and simultaneously nitrogen is doped into the graphitic structure. The NPC/FeCo@NCNT is demonstrated to be an efficient and durable bifunctional catalyst for oxygen evolution (OER) and oxygen reduction reaction (ORR). It only needs an overpotential of 339.5 mV to deliver 10 mA cm−2 for OER and an onset potential of 0.92 V to drive ORR. Its bifunctional catalytic activities outperform those of the composite catalyst Pt/C + RuO2 and most bifunctional catalysts reported. The experimental results and density functional theory calculations have demonstrated that the interplay between FeCo NPs and NCNT and the presence of N,P‐codoped carbon structure play important roles in increasing the catalytic activities of the NPC/FeCo@NCNT. More impressively, the NPC/FeCo@NCNT can be used as the air‐electrode catalyst, improving the performance of rechargeable liquid and flexible all‐solid‐state zinc–air batteries., The FeCo alloy nanoparticles embedded in the N,P‐codoped carbon coated nitrogen‐doped carbon nanotubes (NPC/FeCo@NCNT) have been synthesized and demonstrated to be efficient and durable catalysts for oxygen evolution and reduction reactions. It is usable as the air‐electrode catalysts to improve the performance of rechargeable liquid and flexible all‐solid‐state zinc–air batteries.

Dye-sensitized solar cells (DSSCs) have gained increasing attention with regard to photovoltaic devices, because of their low cost and simple fabrication methods; they are mostly investigated in indoor light-harvesting and portable applications. The focus has been on three main parameters of photovoltaic devices, that is, lifetime, and cost effectiveness. A DSSC consists of four prominent components including a photoanode, a photosensitizer, a redox electrolyte, and a counter electrode. The counter electrode is a crucial component, in which triiodide is reduced to iodide by electrons flowing through the external circuit. An effective approach to improve the performance of a counter electrode is to enhance the power conversion efficiency and to reduce the cost of the device. Platinum-coated conducting glass electrodes give the best performance, but their high cost and the scarcity of platinum restricts large-scale application in DSSCs. This has prompted researchers to develop low-costing platinum-free electrodes for DSSCs. In this review, we focus mainly on counter electrode materials for the electrocatalytic redox reaction for the I−/ electrolyte, and apart from this, other counter electrode materials for iodine-free redox electrolytes are discussed. Different counter electrode materials are highlighted in different categories such as carbon materials, conducting polymers, oxide and sulfide materials, transition-metal nitrides and carbides, and composite materials. The stability of counter electrodes in DSSCs is also presented.

Solvent-free syntheses of quinazolin-4(3H)-ones were performed by reaction of anthranillic acid with different amides, such as nicotinamide, benzamide, formamide, etc., on montmorillonite K-10. Pro...