Transition-metal sulfides (TMSs) powered by conversion and/or alloying reactions are considered to be promising anode materials for advanced lithium-ion batteries (LIBs) and sodium-ion batteries (SIBs). However, the limited electronic conductivity and large volume expansion severely hinder their practical application. Herein, we report a covalent coupling strategy for TMS-based anode materials using amide linkages to bind TMSs and carbon nanotubes (CNTs). In the synthesis, the thiourea acts as not only the capping agent for morphology control but also the linking agent for the covalent coupling. As a proof of concept, the covalently coupled ZnS/CNT composite (CC-ZnS/CNT) has been prepared, with ZnS nanoparticles (∼10 nm) tightly anchored on CNT bundles. The compact ZnS-CNT heterojunctions are greatly beneficial to facilitating the electron/ion transfer and ensuring structural stability. Due to the strong coupling interaction between ZnS and CNTs, the composite presents prominent pseudocapacitive behavior and highly reversible electrochemical processes, thus leading to superior long-term stability and excellent rate capability, delivering reversible capacities of 333 mAh g–1 at 2 A g–1 over 4000 cycles for LIBs and 314 mAh g–1 at 5 A g–1 after 500 cycles for SIBs. Consequently, CC-ZnS/CNT exhibits great competence for applications in LIBs and SIBs, and the covalent coupling strategy is proposed as a promising approach for designing high-performance anode materials.

Three-dimensional (3D) printing technology is becoming a promising method for fabricating highly complex ceramics owing to the arbitrary design and the infinite combination of materials. Insufficient density is one of the main problems with 3D printed ceramics, but concentrated descriptions of making dense ceramics are scarce. This review specifically introduces the principles of the four 3D printing technologies and focuses on the parameters of each technology that affect the densification of 3D printed ceramics, such as the performance of raw materials and the interaction between energy and materials. The technical challenges and suggestions about how to achieve higher ceramic density are presented subsequently. The goal of the presented work is to comprehend the roles of critical parameters in the subsequent 3D printing process to prepare dense ceramics that can meet the practical applications.

a consequence, generally, a barrier layer needs to be introduced to prevent chemical interaction between Oxide fibre/oxide matrix composites form an fibre and matrix. In this paper, some of the issues in important and attractive subpart of ceramic matrix composites because of their inherent stability in the development of oxide fibre/oxide matrix composoxidising atmospheres at high temperatures. An ites, with a particular emphasis on interface tailoring important attribute of such composites, however, to obtain a non-catastrophic failure, are described.is that the interfacial bond between oxide matrix Oxides are inherently resistant to oxidation. However, and oxide fibre is generally very strong, and mixed oxides and glasses with low melting points can consequently, the toughness and damage form in the presence of other oxides or of other tolerance of such composites are low. One way to impurities together with oxygen.overcome this problem is to tailor the interface While there has been a flurry of research activity such that the energy dissipating phenomena such in the area of fibre-reinforced CMCs, that in composas debonding and crack deflection at the fibre/ ite systems showing high strength and high toughness matrix interface, followed by fibre pullout are brought into play. In this paper, the salient aspects at high temperatures and in air are rather minimal. of control of interface characteristics in oxide Non-oxide fibre/non-oxide matrix composites, such fibre/oxide matrix composites, with emphasis on as SiC/SiC,2 have received the greatest attention. composites consisting of alumina and mullite These composites generally show good low temperbased oxide fibres in a variety of oxide matrixes, ature strength, but oxidation resistance is a major are reviewed. IMR/355 limitation.3,4 Mah et al.4 observed that the strength of SiC fibre was very sensitive to temperature above

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