Metal sulfides, such as MoS2, are widely investigated in lithium–sulfur (Li–S) batteries to suppress the shuttling of lithium polysulfides (LiPSs) due to their chemical adsorption ability and catalytic activity. However, their relatively low conductivity and activity limit the LiPS conversion kinetics. Herein, the Co-doped MoS2 is proposed to accelerate the catalytic conversion of LiPS as the Co doping can promote the transition from semiconducting 2H phase to metallic 1T phase and introduce the sulfur vacancies in MoS2. A one-step hydrothermal process is used to prepare such a Co-doped MoS2 with more 1T phase and rich sulfur vacancies, which enhances the electron transfer and catalytic activity, thus effectively improving the LiPS adsorption and conversion kinetics. The cathode using the three-dimensional graphene monolith loaded with Co-doped MoS2 catalyst as the sulfur host shows a high rate capability and long cycling stability. A high capacity of 941 mAh g–1 at 2 C and a low capacity fading of 0.029% per cycle at 1 C over 1000 cycles are achieved, suggesting the effectively suppressed LiPS shuttling and improved sulfur utilization. Good cyclic stability is also maintained under a high sulfur loading indicating the doping is an effective way to optimize the metal sulfide catalysts in Li–S batteries.

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Lithium sulfide (Li 2 S) is a promising cathode for a practical lithium-sulfur battery as it can be coupled with various safe lithium-free anodes. However, the high activation potential (>3.5 V) together with the shuttling of lithium polysulfides (LiPSs) bottleneck its practical uses. We are trying to present a catalysis solution to solve both problems simultaneously, specially with twinborn heterostructure to shoot off the trouble in interfacial contact between two solids, catalyst and Li 2 S. As a typical example, a Co 9 S 8 /Li 2 S heterostructure is reported here as a novel self-catalytic cathode through a co-recrystallization followed by a one-step carbothermic conversion. Co 9 S 8 as the catalyst effectively lowers the Li 2 S activation potential (<2.4 V) due to fully integrated and contacted interfaces and consistently promotes the conversion of LiPSs to suppress the shuttling. The obtained freestanding cathode of Co 9 S 8 /Li 2 S heterostructures encapsulated in three-dimensional graphene shows a high capacity, reaching 92.6% of Li 2 S theoretical capacity, high rate performance (739 mAh g À1 at 2 C), and a low capacity fading (0.039% per cycle at 1 C over 900 cycles). Even under a high Li 2 S loading of 12 mg cm À2 and a low E/S ratio of 5 μL mg Li 2 S À1 , 86% of theoretical capacity can be utilized.Zejian Li and Chong Luo contributed equally to this study.

Periodontopathic bacteria constantly stimulate the host, which causes an immune response, leading to host‐induced periodontal tissue damage. The complex interaction and imbalance between Th17 and Treg cells may be critical in the pathogenesis of periodontitis. Furthermore, the RANKL/RANK/OPG system plays a significant role in periodontitis bone metabolism, and its relationship with the Th17/Treg cell imbalance may be a bridge between periodontal bone metabolism and the immune system. This article reviews the literature related to the Th17/Treg cell imbalance mediated by pathogenic periodontal microbes, and its mechanism involving RANKL/RANK/OPG in periodontitis bone metabolism, in an effort to provide new ideas for the study of the immunopathological mechanism of periodontitis.

Catalysis is an effective remedy for the fast capacity decay of lithium‐sulfur batteries induced by the shuttling of lithium polysulfides (LiPSs), but too strong adsorption ability of many catalysts toward LiPSs increases the risk of catalyst passivation and restricts the diffusion of LiPSs for conversion. Herein, perovskite bimetallic hydroxide (CoSn(OH)6) nanocages are prepared, which are further wrapped by reduced graphene oxide (rGO) as the catalytic host for sulfur. Because of the coordinated valence state of Co and Sn and the intrinsic defect of the perovskite structure, such bimetallic hydroxide delivers moderate adsorption ability and enhanced catalytic activity toward LiPS conversion. Coupled with the hollow structure and the wrapped rGO as double physical barriers, the redox reaction kinetics, and sulfur utilization are effectively improved with such a host. The assembled battery delivers a good rate performance with a high capacity of 644 mAh g−1 at 2 C and long stability with a capacity decay of 0.068% per cycle over 600 cycles at 1 C. Even with a higher sulfur loading of 3.2 mg cm−2 and a low electrolyte/sulfur ratio of 5 µL mg−1, the battery still shows high sulfur utilization and good cycling stability.

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Design intelligence is an important branch of artificial intelligence (AI), focusing on the intelligent models and algorithms in creativity and design. In the context of AI 2.0, studies on design intelligence have developed rapidly. We summarize mainly the current emerging framework of design intelligence and review the state-of-the-art techniques of related topics, including user needs analysis, ideation, content generation, and design evaluation. Specifically, the models and methods of intelligence-generated content are reviewed in detail. Finally, we discuss some open problems and challenges for future research in design intelligence.