Aqueous zinc-ion batteries (AZIBs) have garnered significant attention for large-scale applications due to their low cost, safety, and eco-friendliness. Among all cathode materials, Prussian blue and its analogues (PBAs) have garnered significant attention and been subjected to extensive research due to their diverse property-effectiveness, simple synthesis process, reversible Zn²⁺ insertion/removal capability, and other notable characteristics. However, numerous studies have revealed that the utilization of PBAs as a cathode material in AZIBs still presents certain challenges, including limited energy density and prolonged structural instability during cycling. In light of the aforementioned opportunities and challenges for PBAs, we conducted a comprehensive literature review encompassing synthesis, analysis of energy storage mechanisms, enhancement of electrolyte–electrode interfaces, and battery applications. The objective of this review is to encourage active engagement from researchers interested in AZIBs and PBA cathode materials, thereby fostering research and industrialization efforts that collectively contribute towards the advancement of safe and environmentally friendly energy storage.

In the field of industrial wastewater treatment, membrane separation technology, as an emerging separation technology, compared with traditional separation technology such as precipitation, adsorption, and ion exchange, has advantages in separation efficiency, low energy consumption, low cost, simple operation, and no secondary pollution. The application has been expanding in recent years, but membrane fouling and other problems have seriously restricted the development of membrane technology. Natural cellulose is one of the most abundant resources in nature. In addition, nanocellulose has characteristics of high strength and specific surface area, surface activity groups, as well as being pollution-free and renewable, giving it a very wide development prospect in many fields, including membrane separation technology. This paper reviews the current status of nanocellulose filtration membrane, combs the widespread types of nanocellulose and its derivatives, and summarizes the current application of cellulose in membrane separation. In addition, for the purpose of nanocellulose filtration membrane in wastewater treatment, nanocellulose membranes are divided into two categories according to the role in filtration membrane: the application of nanocellulose as membrane matrix material and as a modified additive in composite membrane in wastewater treatment. Finally, the advantages and disadvantages of inorganic ceramic filtrations and nanocellulose filtrations are compared, and the application trend of nanocellulose in the filtration membrane direction is summarized and discussed.