Water‐Induced Growth of a Highly Oriented Mesoporous Graphitic Carbon Nanospring for Fast Potassium‐Ion Adsorption/Intercalation Storage

A highly oriented mesoporous graphitic carbon nanospring (OGCS) with graphitic layers that are perpendicular to the axis is prepared by hydrothermal treatment of epoxy resin at 500 °C and annealing at 1400 °C. Water plays an important role in not only forming the graphitic carbon nanospring with a high [002] orientation and a large amount of active edge‐plane sites, but also in the generation of the mesoporous structure, which facilitate fast K‐ion adsorption and diffusion. In situ and ex situ measurements confirm that OGCS undergoes K‐adsorption in mesopores and then K‐intercalation in the graphite layer to form KC₈ with a low discharge voltage. The spring‐like nanostructure can expand one‐dimensionally along the axial direction to accommodate the volume variation. The OGCS electrode thus shows a much better K‐storage performance than that of unoriented graphitic carbon.     

Highly Crystalline Mesoporous Phosphotungstic Acid: A High‐Performance Electrode Material for Energy‐Storage Applications

Heteropoly acids (HPAs) are unique materials with interesting properties, including high acidity and proton conductivity. However, their low specific surface area and high solubility in polar solvents make them unattractive for catalytic or energy applications. This obstacle can be overcome by creating nanoporosity within the HPA. We synthesized mesoporous phosphotungstic acid (mPTA) with a spherical morphology through the self‐assembly of phosphotungstic acid (PTA) with a polymeric surfactant as stabilized by KCl and hydrothermal treatment. The mPTA nanostructures had a surface area of 93 m² g^?1 and a pore size of 4 nm. Their high thermal stability (ca. 450 °C) and lack of solubility in ethylene carbonate/diethyl carbonate (EC/DEC) electrolyte are beneficial for lithium‐ion batteries (LIBs). Optimized mPTA showed a reversible capacity of 872 mAh g^?1 at 0.1 A g^?1 even after 100 cycles for LIBs, as attributed to a super‐reduced state of HPA and the storage of Li ions within the mesochannels of mPTA.     

Electrochemically Assisted Generation of Highly Ordered Azide‐Functionalized Mesoporous Silica for Oriented Hybrid Films

One key challenge in inorganic mesoporous films is the development of oriented mesostructures with vertical channels, and even more challenging is their functionalization while maintaining accessible the selected surface groups. Combining the electrochemically assisted deposition of ordered and oriented azide‐functionalized mesoporous silica with alkyne–azide click chemistry enables such nanostructured and vertically aligned hybrid films to be obtained with significant amounts of active organic functional groups, as illustrated for ferrocene and pyridine functions. A good level of mesostructural order was obtained, namely up to 40 % of organosilane in the starting sol. The method could be applied to a wide variety of functional groups, thus offering numerous new opportunities for applications in various fields.