Electrochromic devices have many important commercial applications ranging from electronic paper like displays, antiglare rear‐view mirrors in cars, to energy‐saving smart windows in buildings. Monovalent ions such as H+, Li+, and Na+ are widely used as insertion ions in electrochromic devices but have serious limitations such as instability, high‐cost, and hard handling. The utilization of trivalent ions as insertion ions has been largely overlooked probably because of the strong electrostatic interactions between ions and intercalation framework and the resulted difficulties of intercalation. It is demonstrated that the trivalent ion, Al3+, can be used as efficient insertion ion by using metal oxide hosts in nanostructured form, which brings the desired fast‐switch, high‐contrast, and high‐stability as well to electrochromic devices. Differing from the usual structure degradation by repeated guest intercalation/deintercalation, the Al3+ insertion introduces strong electrostatic forces, which on some degree stabilize the crystal structure and consequently yield much enhanced performances.

A few-layered Ti3C2nanosheet/glass fiber composite separator was designed and fabricated as a lithium polysulphide reservoir for high-performance lithium–sulfur batteries.

A recent technological trend in the field of electrochemical energy storage is to integrate energy storage and electrochromism functions in one smart device, which can establish efficient user-device interactions based on a friendly human-readable output. This type of newly born energy storage technology has drawn tremendous attention. However, there is still plenty of room for technological and material innovation, which would allow advancement of the research field. A prototype Al-tungsten oxide electrochromic battery with interactive color-changing behavior is reported. With the assistance of trace amount of H2 O2 , the battery exhibits a specific capacity almost seven times that for the reported electrochromic batteries, up to 429 mAh g(-1) . Fast decoloration of the reduced tungsten oxide affords a very quick charging time of only eight seconds, which possibly comes from an intricate combination of structure and valence state changes of tungsten oxide. This unique combination of features may further advance the development of smart energy storage devices with suitability for user-device interactions.

The strong interest in macroscopic graphene and/or carbon nanotube (CNT) fiber has highlighted that anisotropic nanostructured materials are ideal components for fabricating fiber assemblies. Prospectively, employing two-dimensional (2D) crystals or nanosheets of functionality-rich transition metal oxides would notably enrich the general knowledge for desirable fiber constructions and more importantly would greatly broaden the scope of functionalities. However, the fibers obtained up to now have been limited to carbon-related materials, while those made of 2D crystals of metal oxides have not been achieved, probably due to the intrinsically low mechanical stiffness of a molecular sheet of metal oxides, which is only few hundredths of that for graphene. Here, using 2D titania sheets as an illustrating example, we present the first successful fabrication of macroscopic fiber of metal oxides composed of highly aligned stacking sheets with enhanced sheet-to-sheet binding interactions. Regardless of the intrinsically weak Ti-O bond in molecular titania sheets, the optimal fiber manifested mechanical performance comparable to that documented for graphene or CNTs. This work provided important hints for devising optimized architecture in macroscopic assemblies, and the rich functionalities of titania promises fibers with limitless promise for a wealth of innovative applications.

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This study performs the spatial Durbin model (SDM) and threshold model to analyze the efficiency of agricultural green production following technological progress from 1998 through 2019. The SDM supports a nonlinear contribution of technological progress spillover to agricultural green total factor productivity (GTFP), exacerbated by upgrading agricultural structure. Moreover, the threshold model confirms that technological progress has a single threshold effect on agricultural GTFP with the rationalization of the agrarian system as a threshold variable; meanwhile, the contribution of technological progress to agricultural GTFP is less than that of agricultural total factor productivity. Out of the expanded application of dissipative structure theory in agricultural GTFP systems innovatively, this study reveals the urgency to strengthen the innovation of independent technology, lower the threshold for introducing technology, and optimize the agrarian structure in the long-term sustainable agriculture for the economies that are undergoing a similar development stage as China.

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