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Hydrogen production, which is in the spotlight as a promising eco-friendly fuel, and the need for inexpensive and accurate electronic devices in the biochemistry field are important emerging technologies. However, the use of electrocatalytic devices based on expensive noble metal catalysts limits commercial applications. In recent years, to improve performance and reduce cost, electrocatalysts based on cheaper copper or nickel materials have been investigated for the non-enzymatic glucose oxidation reaction (GOR) and hydrogen evolution reaction (HER). In this study, we demonstrate a facile and easy electrochemical method of forming a cheap nickel copper double hydroxide (NiCu-DH) electrocatalyst deposited onto a three-dimensional (3D) CuNi current collector, which can effectively handle two different reactions due to its high activity for both the GOR and the HER. The as-prepared electrode has a structure comprising abundant 3D-interconnected porous dendritic walls for easy access of the electrolyte ions and highly conductive networks for fast electron transfer; additionally, it provides numerous electroactive sites. The synergistic combination of the dendritic 3D-CuNi with its abundant active sites and the self-made NiCu-DH with its excellent electrocatalytic activity toward the oxidation of glucose and HER enables use of the catalyst for both reactions. The as-prepared electrode as a glucose sensor exhibits an outstanding glucose detection limit value (0.4 μM) and a wide detection range (from 0.4 μM to 1.4 mM) with an excellent sensitivity of 1452.5 μA/cm

High-energy density lithium-oxygen batteries (LOBs) seriously suffer from poor rate capability and cyclability due to the slow oxygen-related electrochemistry and uncontrollable formation of lithium peroxide (Li

Silicon microparticles (SiMPs), which have a high capacity, a high initial Coulombic efficiency, and a low volume-to-surface ratio compared with nanosized materials, are promising anode materials f...

We report a Co3O4 exsolved perovskite oxide PrBaMn1.7Co0.3O5+δ (Co3O4–PBMCO) that utilizes the Faradaic transfer of metal oxide and favorable OH– adsorption for an energy storage mechanism, as an a...

Porous graphitic carbon produced from waste coffee grounds (WCG), enormous amounts of which are generated and thrown away worldwide every year, is demonstrated as an effective broadband solar photo...

Reduced graphene oxide (rGO) composites for energy-related applications have attracted increasing attention. However, previous studies on rGOs still showed limitations because of unresolved several...

A carbon electrode was designed to guarantee flexibility of symmetric electric double layer capacitors (EDLCs) based on its architecture. Three different dimensional carbon materials were combined ...

We report that metal ions (M: Sn4+ and Ti4+) and boron-codoped hematite photoanodes with an n–n+ homojunction showed significantly increased photoelectrochemical (PEC) water splitting activity with...

We present a facile yet efficient single-step pyrolysis method to prepare bulk-scale high-performance N-doped 3D-graphitic foams with various length-scale pores. The iron precursors act as catalysts for the conversion of organic substances to a graphitic structure while simultaneously providing a rigid template that prevents the aggregation of organic components, and soluble polymers act as a carbon source for the formation of N-doped multilayer graphene under high-temperature and inert conditions. The 3D-graphitic foams possess highly interconnected networks composed of micro-, meso-, and macropores with a specific surface area of up to 1509 m2 g–1 and a high conductivity of 10 S m–1. The resulting 3D-graphitic foams exhibited specific capacitance values of 330 and 242 F g–1 with outstanding cycling stability (a 23% loss after 100 000 cycles for a symmetric cell) in a three-electrode system and in a symmetric cell, respectively, when used as active materials in a supercapacitor. This study suggests the g...

By coupling α-Fe2O3 with a 3D graphene inverse opal (3D-GIO) conducting electrode, the short diffusion length of carriers and low absorption coefficient in α-Fe2O3 for photoelectrochemical applications were successfully addressed. GIO was directly grown on FTO substrate under low temperature conditions, removing the need for a graphene transfer process. α-Fe2O3 nanoparticles (NPs) were hydrothermally deposited on the surface of GIO, creating α-Fe2O3/GIO. The photocurrent density of α-Fe2O3/GIO in water splitting reactions reached 1.62 mA/cm(2) at 1.5 V vs RHE, which is 1.4 times greater than that of optimized α-Fe2O3. The EIS and IPCE data confirm reduced electron-hole recombination and fast electron transfer processes due to the short distance between active materials and the conducting electrode in the α-Fe2O3/GIO system. Our result may pave the way for designing devices in advanced energy conversion applications as well as a high efficiency hematite-based PEC system.

Pattern transformation in periodic microporous elastoplastic solid coatings is caused by a buckling of the struts and a rotation of the nodes under compressive stresses. The results of a nonlinear numerical investigation confirm the critical role of the bifurcation of the periodic solid under compressive stresses. In striking contrast to the earlier observations of elastic instabilities in porous elastomeric solids, the elastic-plastic nature of the cross-linked periodic microstructure studied here provides the ability to lock in the transformed pattern with complete relaxation of the internal stresses. The study unveils a novel deformation mode in porous periodic solids in the form of organized buckling instability of weak strut elements.

Phase mask interference lithography was employed to fabricate three-dimensional (3D) hydrogel structures with high surface area on neural prosthetic devices. A random terpolymer of poly(hydroxyethyl methacrylate-ran-methyl methacrylate-ran-methacrylic acid) was synthesized and used as a negative-tone photoresist to generate bicontinuous 3D hydrogel structures at the submicrometer scale. We demonstrated that the fully open 3D hydrogel/air networks can be used as a pH-responsive polymeric drug-release system for the delivery of neurotrophins to enhance the performance of neural prosthetic devices. Additionally an open hydrogel structure will provide direct access of neuronal growth to the device for improved electrical coupling.