Zeolite Beta single crystals with intracrystalline hierarchical porosity at macro-, meso-, and micro-length scales can effectively overcome the diffusion limitations in the conversion of bulkym olecules.H owever,t he construction of large zeolite Beta single crystals with such porosity is ac hallenge.W er eport herein the synthesis of hierarchically ordered macro-mesoporous single-crystalline zeoliteB eta (OMMS-Beta) with ar are micron-scale crystal size by an in situ bottom-up confined zeolite crystallization strategy.The fully interconnected intracrystalline macro-meso-microporous hierarchy and the micron-sized single-crystalline nature of OMMS-Beta lead to improved accessibility to active sites and outstanding (hydro)thermal stability.Higher catalytic performances in gas-phase and liquid-phase acid-catalyzed reactions involving bulkymolecules are obtained compared to commercial Beta and nanosized Beta zeolites.T he strategy has been extended to the synthesis of other zeolitic materials,i ncluding ZSM-5, TS-1, and SAPO-34.
The severe shuttling behavior in the discharging–charging process largely hampers the commercialization of lithium–sulfur (Li–S) batteries. Herein, we design a bifunctional separator with an ultra-lightweight MnO2 coating to establish strong chemical adsorption barriers for shuttling effect alleviation. The double-sided polar MnO2 layers not only trap the lithium polysulfides through extraordinary chemical bonding but also ensure the uniform Li+ flux on the lithium anode and inhibit the side reaction, resulting in homogeneous plating and stripping to avoid corrosion of the Li anode. Consequently, the assembled Li–S battery with the MnO2-modified separator retains a capacity of 665 mA h g–1 at 1 C after 1000 cycles at the areal sulfur loading of 2.5 mg cm–2, corresponding to only 0.028% capacity decay per cycle. Notably, the areal loading of ultra-lightweight MnO2 coating is as low as 0.007 mg cm–2, facilitating the achievement of a high energy density of Li–S batteries. This work reveals that the polar metal oxide-modified separator can effectively inhibit the shuttle effect and protect the Li anode for high-performance Li–S batteries.
The combination of hetero‐elemental doping and vacancy engineering will be developed as one of the most efficient strategies to design excellent electrocatalysts for hydrogen evolution reaction (HER). Herein, a novel strategy for N‐doping coupled with Co‐vacancies is demonstrated to precisely activate inert S atoms adjacent to Co‐vacancies and significantly improve charge transfer for CoS toward accelerating HER. In this strategy, N‐doping favors the presence of Co‐vacancies, due to greatly decreasing their formation energy. The as‐developed strategy realizes the upshift of S 3p orbitals followed by more overlapping between S 3py and H 1s orbitals, which results in the favorable hydrogen atom adsorption free energy change (ΔGH) to activate inert S atoms as newborn catalytical sites. Besides, this strategy synergistically decreases the bandgap of CoS, thereby achieving satisfactory electrical conductivity and low charge‐transfer resistance for the as‐obtained electrocatalysts. With an excellent HER activity of −89.0 mV at 10.0 mA cm−2 in alkaline environments, this work provides a new approach to unlocking inert sites and significantly improving charge transfer toward cobalt‐based materials for highly efficient HER.
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.
hi@scite.ai
10624 S. Eastern Ave., Ste. A-614
Henderson, NV 89052, USA
Copyright © 2024 scite LLC. All rights reserved.
Made with 💙 for researchers
Part of the Research Solutions Family.