Limited lithium resources have promoted the exploration of new battery technologies. Among them, potassium-ion batteries are considered as promising alternatives. At present, commercial graphite and other carbon-based materials have shown good prospects as anodes for potassium-ion batteries. However, the volume expansion and structural collapse caused by periodic K + insertion/extraction have severely restricted further development and application of potassium-ion batteries.A hollow biomass carbon ball (NOP-PB) ternarily doped with N, O, and P was synthesized and used as the negative electrode of a potassium-ion battery. X-ray photoelectron spectroscopy, Fourier-transform infrared spectroscopy, and transmission electron microscopy confirmed that the hollow biomass carbon spheres were successfully doped with N, O, and P.Further analysis proved that N, O, and P ternary doping expands the interlayer distance of the graphite surface and introduces more defect sites. DFT calculations simultaneously proved that the K adsorption energy of the doped structure is greatly improved. The solid hollow hierarchical porous structure buffers the volume expansion of the potassium insertion process, maintains the original structure after a long cycle and promotes the transfer of potassium ions and electrons. Therefore, the NOP-PB negative electrode shows extremely enhanced electrochemical performance, including high specific capacity, excellent long-term stability, and good rate stability.

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Ag–ZnO heterojunction promotes the separation of photogenerated pairs and thus exhibits high catalytic activity under UV-visible light.

Glucose monitoring is essential to evaluate the degree of glucose metabolism disorders. The enzymatic determination has been the most widely used method in glucose detection because of its high efficiency, accuracy, and sensitivity. Noble metal nanomaterials (NMs, i.e., Au, Ag, Pt, and Pd), inheriting their excellent electronic, optical, and enzyme‐like properties, are classified as noble metal nanozymes (NMNZs). As the NMNZs are often involved in two series of reactions, the oxidation of glucose and the chromogenic reaction of peroxide, here the chemical mechanism by employing NMNZs with glucose oxidase (GOx) and peroxidase (POD) mimicking activities is briefly summarized first. Subsequently, the regulation strategies of the GOx‐like, POD‐like and tandem enzyme‐like activities of NMNZs are presented in detail, including the materials, size, morphology, composition, and the reaction condition of the representative NMs. In addition, in order to further mimic the enantioselectivity of enzyme, the design of NMNZs with enantioselective recognition of d‐glucose and l‐glucose by using different chiral compounds (DNA, amino acids, and cyclodextrins) and molecular imprinting is further described in this review. Finally, the feasible solutions to the existing challenges and a vision for future development possibilities are discussed.

The pure, tin (Sn)-doped, lanthanum (La)-doped and Sn/La co-doped titanium dioxide (TiO2) nanomaterials were synthesized using sol-gel method followed by calcination at the temperature of 360 °C, 450 °C and 600 °C, respectively. The structures of the nanomaterials were characterized by X-ray diffraction (XRD), Thermogravimetric (TG), Differential Thermal Analysis (DTA), Scanning Electron Microscopy (SEM), Energy Dispersive Spectrum (EDS), Transmission Electron Microscopy (TEM), X-ray Photoelectron Spectrum (XPS), Diffuse Reflectance Spectrum (DRS), Photoluminescence Spectrum (PL), Brunauer-Emmett-Teller Measurements (BET), respectively. The photocatalytic property of the photocatalysts under UV light was evaluated through the degradation of Rhodamine B (RhB). The results show that the anatase-rutile phase transition is promoted by Sn-doping while La-doping retards the phase transition. However, La doping plays a major role in the process of phase transformation. The photocatalytic activity of pure TiO2 is affected by annealing temperature remarkably and the optimal annealing temperature is 450 °C. The photocatalytic activity of TiO2 is enhanced significantly by Sn and La doping at three different temperatures. Sn/La-TiO2 exhibits the highest degradation rates and the fastest reaction rates probably owing to the synergistic effect of Sn4+ and La3+ ions in inhibiting the recombination of photogenerated electron-hole pairs. The formation of extra surface hydroxyl groups and additional surface area are also beneficial for the photocatalytic activity.