The 3D NiO hollow sphere/reduced graphene oxide (rGO) composite was synthesized according to the coordinating etching and precipitating process by using Cu₂O nanosphere/graphene oxide (GO) composite as template. The morphology, structure, and composition of the materials were characterized by SEM, TEM, HRTEM, XPS, and Raman spectra, and the electrochemical properties were studied by cyclic voltammetry (CV), electrochemical impedance spectroscopy (EIS), and amperometry. Moreover, the electrochemical activity of the composite materials with different morphologies were also investigated, which indicating a better combination of the NiO hollow sphere and the rGO. Used as glucose sensing material, the 3D NiO hollow sphere/rGO composite modified electrode exhibits high sensitivity of ~2.04 mA mM⁻¹ cm⁻², quick response time of less than 5 s, good stability, selectivity, and reproducibility. Its application for the detection of glucose in human blood serum sample shows acceptable recovery and R.S.D. values. The outstanding glucose sensing performance should be attributed to the unique 3D hierarchical porous superstructure of the composite, especially for its enhanced electron-transfer kinetic properties.

We report a facile synthesis strategy for core-branched CoSe ₂ /Ni _0.85 Se nanotube arrays directly on Ni foam by simply selenizing Co-precursor nanowires.

Solar steam generation has emerged as a promising and sustainable method of addressing the water shortage issue. Although various materials and structures have been reported, designing a highly efficient steam generation device with excellent salt resistant performance remains a great challenge. For the first time, a polypyrrole (PPy)–wood device has been prepared through a simple “soak and polymerization” process by in situ polymerization of pyrrole monomers into a three-dimensional (3D) porous wood matrix. The PPy particles decorated on the wood matrix can convert incident light into heat while the 3D porous wood matrix can further enhance light absorption based on light harvesting and multiple scattering effects, which allows the PPy–wood light absorption to reach as high as 97.5% in the spectral range from 250 nm to 2500 nm. Owing to the low thermal conductivity of wood, the PPy–wood can localize the converted heat at the surface of the device, enabling efficient steam generation. The hydrophilicity and the numerous aligned microchannels of the PPy–wood ensure constant water supply to the air–water interface. All these merits endow the PPy–wood with a high solar energy conversion efficiency of 83% under 1 Sun, with an evaporation rate of 1.33 kg m⁻² h⁻¹. Moreover, the fabricated PPy–wood also shows good structure stability and cycling stability as well as excellent salt resistant performance. Benefiting from the low-cost of wood and the simple fabrication process, the PPy–wood with the above merits is one of the most suitable candidates for solar desalination.