Due to a wide band gap and large exciton binding energy, zinc oxide (ZnO) is currently receiving much attention in various areas, and can be prepared in various forms including nanorods, nanowires, nanoflowers, and so on. The reliability of ZnO produced by a single dopant is unstable, which in turn promotes the development of co-doping techniques. Co-doping is a very promising technique to effectively modulate the optical, electrical, magnetic, and photocatalytic properties of ZnO, as well as the ability to form various structures. In this paper, the important advances in co-doped ZnO nanomaterials are summarized, as well as the preparation of co-doped ZnO nanomaterials by using different methods, including hydrothermal, solvothermal, sol-gel, and acoustic chemistry. In addition, the wide range of applications of co-doped ZnO nanomaterials in photocatalysis, solar cells, gas sensors, and biomedicine are discussed. Finally, the challenges and future prospects in the field of co-doped ZnO nanomaterials are also elucidated.

Heterostructure construction and heteroatom doping are powerful strategies for enhancing the electrolytic efficiency of electrocatalysts for overall water splitting. Herein, we present a P-doped MoS₂/Ni₃S₂ electrocatalyst on nickel foam (NF) prepared using a one-step hydrothermal method. The optimized P_[0.9mM]-MoS₂/Ni₃S₂@NF exhibits a cluster nanoflower-like morphology, which promotes the synergistic electrocatalytic effect of the heterostructures with abundant active centers, resulting in high catalytic activity for the hydrogen evolution reaction (HER) and oxygen evolution reaction (OER) in alkaline electrolyte. The electrode exhibits low overpotentials and Tafel slopes for the HER and OER. In addition, the catalyst electrode used in a two-electrode system for overall water splitting requires an ultralow voltage of 1.42 V at 10 mA·cm⁻² and shows no obvious increase in current within 35 h, indicating excellent stability. Therefore, the combination of P doping and the heterostructure suggests a novel path to formulate high-performance electrocatalysts for overall water splitting.

With the continuous depletion of traditional energy sources, the development of sustainable energy sources has become one of the important tasks today. A two-step synthesis method was employed to construct Ni₃S₂/ZrCoFe-LDH@NF heterostructured electrocatalysts on nickel grid (NF) in situ. X-ray diffractometer, scanning electron microscope, transmission electron microscope and X-ray electron spectroscopy were employed to characterize the Ni₃S₂/ZrCoFe-LDH@NF heterostructure, and the HER, OER and total hydrolysis properties of this electrocatalyst were tested in 1 mol·L^− 1 KOH electrolyte. It was shown that Ni₃S₂/ZrCoFe-LDH@NF was a lamellar stacked heterostructure with an overpotential of 330 mV and a Tafel slope of 90.9 mV·dec^− 1 at a current density of 100 mA·cm^− 2 in the OER reaction and 159.2 mV at a current density of 10 mA·cm^− 2 in the OER reaction. Tafel slope was 96 mV·dec^− 1, and the catalyst exhibited good structural stability in the 100 h total hydrolysis stability test. The successful construction of this heterostructured electrocatalyst provides a good idea and research basis for the subsequent heterojunction and its application in electrocatalysis.