Aqueous Zn-ion devices comprising a Zn-metal anode constitute an emerging class of next-generation energy storage devices with the growing demand for renewable energies. Over the past few years, sophisticated strategies have been developed to produce robust electrodes and electrolytes as well as their interface for alleviated Zn dendrite growth and side reactions, yet boosting the electrochemical stability to a commercial level using facile strategies such as an electrolyte additive is still desired. Here, we report scalable electrolyte engineering featuring a hydrophilically tuned nonionic amphiphilic polymer additive to fundamentally suppress water-related side reactions. The polymer additive bearing both hydrophilic and hydrophobic units foster a localized nano-scaled H2O-poor environment that essentially de-solvates Zn2+ from aqueous media. The preferential adsorption of hydrophilic segments on the Zn anode also creates a local hydrophobic layer that synergistically shields the metal from direct aqueous corrosion. Moreover, tuned electrolyte increased anion decomposition on the anode, which further leads to an F-rich and O-deficient interface that promotes the stabilized anode. Consequently, introduction of a trace amphiphilic polymer additive into traditional Zn(OTf)2 leads to a highly stable anode in symmetric and full batteries, represented by ultralong cycling for over 8800 h (367 days) at 1 mA cm−2/1 mA h cm−2 and 2500 h at 5 mA cm−2/5 mA h cm−2 for Zn–Zn cells with added wide-temperature operation from 50 °C down to −30 °C. The principle of building local hydrophobicity in aqueous ionic electrolyte media using a nonionic amphiphilic polymer contributes new understanding of Zn stabilization that may permit near-future industrialization of aqueous Zn-based energy storage.
Mesoporous materials are materials with high surface area and intrinsic porosity, and therefore have attracted great research interest due to these unique structures. Mesoporous titanium dioxide (TiO2) is one of the most widely studied mesoporous materials given its special characters and enormous applications. In this article, we highlight the significant work on mesoporous TiO2 including syntheses and applications, particularly in the field of photocatalysis, energy and biology. Different synthesis methods of mesoporous TiO2—including sol–gel, hydrothermal, solvothermal method, and other template methods—are covered and compared. The applications in photocatalysis, new energy batteries and in biological fields are demonstrated. New research directions and significant challenges of mesoporous TiO2 are also discussed.
11 June 2024 in Angewandte Chemie International Edition