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A high-capacity alkaline redox storage chemistry is explored based on an environmentally benign zirconia-stabilized Fe 6+ /B 2− chemistry. This super-iron boride battery sustains an electrochemical potential matched to the pervasive, conventional MnO 2 -Zn battery chemistry, but with a much higher electrochemical storage capacity. Whereas a conventional alkaline battery pairs the 2e − zinc anode with a 1e − MnO 2 cathode, the new alkaline cell couples an 11e − boride anode, such as VB 2 , with a 3e − storage hexavalent iron cathode. The cell has an open circuit and discharge potential comparable to the conventional, commercial alkaline battery. Based on VB 2 ͑72.6 g mol −1 ͒ and the Fe͑VI͒ salt K 2 FeO 4 ͑198.0 g mol −1 ͒, the super-iron boride cell has an 11 Faraday theoretical capacity of 369 mAh g −1 . Added AgO mediates and further facilitates the 3e − K 2 FeO 4 reductive charge transfer, and we demonstrate for super-iron boride that over 300 mAh g −1 is approached experimentally, which is substantially higher than the conventional Zn/MnO 2 alkaline battery with an experimental capacity ͑to 0.8 V͒ of 160 mAh g −1 and a theoretical capacity of 224 mAh g −1 .

Dural closure after the neurosurgery can prevent postoperative complications. Although many types of dural substitute have been developed, most of them lack functional and structural characteristics compared with the natural dura mater. In this study, we used electrospinning method to fabricate a multilayer scaffold to promote dural repair. The inner layer of the scaffold that faces the brain tissue is composed of poly-lactic acid (PLA) to reduce tissue adhesion. The middle layer of the scaffold is composed of poly-ɛ-caprolactone and PLA, which provides a watertight seal. The outer layer of the scaffold contains a large amount of collagen to promote cell attachment and proliferation. The results from in vitro study and an animal model have shown that this multilayer fibrous scaffold has sufficient mechanic strength and biochemical properties to enhance dural repair. Therefore, fabrication of scaffold with multiple functional and structural layers may provide a novel approach for tissue engineering.