The ORCID identification number(s) for the author(s) of this article can be found under https://doi.org/10.1002/adma.201805430.
Anode MaterialsLithium-ion batteries (LIBs) have been playing a vital role in the development of portable electronics for the last couple of decades, thanks to their high energy storage capabilities and longer cyclic lives. However, the long-term applications of LIBs at larger scale (such as automotive) face severe challenges due
SnS with high theoretical capacity has been impeded from practical applications as the anode of lithium-ion (Li-ion) batteries due to its large volume expansion and fast capacity decay. A nanostructure of the SnS semifilled carbon nanotube (SnS@CNT) has been realized by plasma-assisted fabrication of Sn semifilled CNT (Sn@CNT) followed by post-sulfurization. When serving as the anode of a Li-ion battery, SnS@CNT delivers an initial discharge capacity of 1258 mAh g at 0.3 A g. Instead of capacity fading, SnS@CNT shows inverse capacity growth to 2733 mAh g after 470 cycles. The high-resolution transmission electron microscopy images show that the void in CNTs, after cycling, is fully filled with pulverized SnS grains which have a shortened Li-ion diffusion path and enhanced surface area for interfacial redox reactions. In addition, the CNTs, like a pocket, confine the pulverized SnS, maintain the electric contact and structural integrity, and thus allow the electrodes to work safely under long cyclic loadings and extreme temperature conditions.
The development of advanced energy conversion systems such as fuel cells and electrolyzers with desirable efficiency and durability is of great significance in order to power society in a sustainable way, which highly depends on the fabrication of electrocatalysts with desirable electrochemical performance. Multi‐scale design of electrocatalysts from the atomic scale to device‐scale is crucial to achieve optimal overall electrochemical performance in terms of activity, selectivity, and durability. Benefitting from their highly diverse and tunable structures and compositions, metal–organic frameworks (MOFs) are promising platforms to design and synthesize electrocatalysts at multiple scales for energy electrocatalysis. Herein, the fundamental principles and recent progress in multi‐scale design of MOF‐derived materials from the aspects of active sites, interfaces, pore structures, and morphologies are summarized. Moreover, precise control of these variables, to meet the requirements of specific energy‐related reactions including oxygen reduction reaction, oxygen evolution reaction, hydrogen evolution reaction, CO2 reduction reaction (CO2RR), and N2 reduction reaction is critically discussed. Furthermore, challenges and future research directions in multi‐scale design and fabrication of MOF‐derived electrocatalysts for real‐world energy conversion applications are provided.
The present article introduces the auxiliary energy assisted friction stir welding (FSW) processes purported to overcome the shortcomings of the conventional FSW process. The auxiliary energies used for this purpose are thermal energy from electric resistance heat, induction heat, laser, plasma, arc, etc. and mechanical energy in the form of ultrasonic vibration. The state-of-the-art, experimentation and progresses in these FSW variants are surveyed and compiled. The auxiliary energy assisted FSW processes exhibit great promise by having numerous advantages over the conventional FSW in terms improved process window, heat generation, material flow, reduced load on the tools and mechanical properties of joints. Such remarkable advantages would lead these processes to redefine many global technologies and markets in the twenty-first century. However, these variants are still in their preliminary stages of investigation, and more systematic investigations are necessary for their critical assessment. In this aspect, some unsolved issues and challenges are overlooked.
scite is a Brooklyn-based organization that helps researchers better discover and understand research articles through Smart Citations–citations that display the context of the citation and describe whether the article provides supporting or contrasting evidence. scite is used by students and researchers from around the world and is funded in part by the National Science Foundation and the National Institute on Drug Abuse of the National Institutes of Health.