Adding an eggshell membrane (ESM) template to the solution combustion synthesis of NiMoO 4 resulted in the formation of -NiMoO 4 under mild conditions. It is postulated that the unique nature of the ESM template results in interactions that stabilise this difficult to synthesise form of NiMoO 4 .The ESM template led to -NiMoO 4 particles that were nano-wire like in shape and arranged in an open weave structure that significantly enhanced the mesoporosity and conductance of the material. The specific capacitance was measured as 259 F g-1 in a two electrode system with an energy density of 252.2 W h kg-1. The results indicate that the use of a fibrous like natural polymeric materials as templates stabilises materials in preferred crystal forms and shapes leading to much improved electrochemical performance. Keywords Superconductors, Energy storage and conversion, Nickel molybdate, template, nanowire, eggshell membrane 1 Introduction Large-scale uptake of clean and sustainable energy generation has led to much effort being devoted to the development of novel energy storage solutions to cater for the intermittent nature of the energy output from these renewable sources [1-6]. Supercapacitors are considered a promising technology in this area as they provide higher power and energy density than traditional batteries coupled with fast recharge ability, high energy storage capability, good rate performance, and long cycling stability [7]. Traditionally, supercapacitors have been available in two forms based on their charge storage mechanism. Electrical double-layer capacitors (EDLC) store energy at the electrode/electrolyte interface, while pseudocapacitors utilise electron transfer faradaic reactions in a suitable electrolyte. Hybrids of these traditional forms are now being actively investigated where both storage mechanisms can be accessed, resulting in devices with much higher capacitance and a broader range of applications [8,9]. An essential part of the development of hybrid supercapacitors is the investigation of novel active materials for electrode manufacture [10-12 ]. Mixed metal oxides are a promising area due to the availability of multiple oxidation states and relative earth abundant starting materials [13-16]. Mixed metal molybdates, especially those incorporating Ni, are particularly interesting materials, exhibiting high specific capacitance and energy density [17-20]. This improved performance is attributed to the fact that NiMoO 4 is more chemically active than other molybdates (Mg, Co, etc.) and exhibit a greater density of oxidation states near the top of the valence band [21,22]. There are two main ways to increase the performance of a hybrid supercapacitor electrode: increase the surface area and manipulate the material to improve conductance. The former can be achieved by synthesising nano-sized particles with interesting shapes or a porous nature that allow maximum access to the surface of the material or by simply increasing porosity without resorting to the nanoscale [23-25]. Improvement in c...

Abstract. In order to take advantage of the increasing sophistication of technology for harnessing renewable energy resources, serious attention must be paid to how to store and re-access this energy. Electrochemical storage, in the guise of batteries, supercapacitors and pseudocapacitors, has attracted much attention as a viable option for enhanced energy storage applications. But in order for these technologies to be implemented successfully we need to find materials that perform better and are relatively easy to synthesise. Bimetallic transition metal oxides are materials that are readily synthesised and may be multifunctional, i.e. have a role at the electrochemical atomic level as well as the device level. In order for these materials to work efficiently in new generation systems based on sodium and lithium they also need to be mesoporous. This can be achieved by trying to find synthetic techniques that produce specific, highly regulated nanostructures or by adding a 'templating' agent during the bulk synthesis step. We have investigated the simple hydrothermal preparation of a number of nickel cobaltate (NiCo 2 O 4 ) materials using polymer templates, eggshell membrane (ESM) and poly methyl methacrylate (PMMA), as potential electrode materials for supercapacitors. The ESM was expected to act as a fibrous, random polymeric template while the PMMA should produce a much more ordered material. Electrochemical testing showed that the different templates have led to changes in material morphology and these have resulted in a difference in electrochemical properties. Templated materials increased specific capacitance compared to non-templated and the choice of template could influence the capacitance by as much as 30%.