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Three-dimensional-printed silicone rubber foams, with their designable and highly ordered pore structures, have shown exceptional potential for engineering applications, particularly in areas requiring energy absorption and cushioning. However, optimizing the mechanical properties of these foams through structural design remains a significant challenge. This study addresses this challenge by formulating the research question: How do different 3D-printed topologies and printing parameters affect the mechanical properties of silicone rubber foams, and how can we design a novel topological structure? To answer this, we explored the mechanical behavior of two common structures–simple cubic (SC) and face-centered tetragonal (FCT)–by varying printing parameters such as filament spacing, filament diameter, and layer height. Furthermore, we proposed a novel two-level 3D-printed structure, combining SC and FCT configurations to enhance performance. The results demonstrated that the two-level SC-SC structure exhibited a specific energy absorption of 8.2 to 21.0 times greater than the SC structure and 2.3 to 7.2 times greater than the FCT structure. In conclusion, this study provides new insights into the design of 3D-printed silicone rubber foams, offering a promising approach to developing advanced cushioning materials with superior energy absorption capabilities. [ABSTRACT FROM AUTHOR]

Silicone rubber molds were treated with air plasma and used to prepare polyvinyl alcohol/polyvinylpyrrolidone water-soluble microneedles. The effects of plasma treatment on mold wettability, coating adhesion, micro-needle yield and mechanical properties were discussed. The results showed that plasma treatment could generate polar hydrophilic groups on the surface of the mold, improve the wettability of the mold, the adhesion of polyvinyl alcohol/polyvinylpyrrolidone coating, and elevate the yield rate of micro-needles and the overall mechanical properties. With the prolongation of plasma treatment time, the wettability of the mold, the yield rate of microneedles and the mechanical properties increased increased and then decreased. When the silicone rubber mold was treated with air plasma for 6-8 minutes, water-soluble microneedles with a complete structure, good mechanical property and easy demolding ability could be prepared. [ABSTRACT FROM AUTHOR]

Single-crystal lithium-rich layered oxides (LLOs) with excellent mechanical properties can enhance their crystal structure stability. However, the conventional methods for preparing single-crystal LLOs, require large amounts of molten salt additives, involve complicated washing steps, and increase the difficulty of large-scale production. In this study, a sodium tungstate (Na 2 WO 4 )-assisted sintering method is proposed to fabricate high-performance single-crystal LLOs cathode materials without large amounts of additives and additional washing steps. During the sintering process, Na 2 WO 4 promotes particle growth and forms a protective coating on the surface of LLOs particles, effectively suppressing the side reactions at the cathode/electrolyte interface. Additionally, trace amounts of Na and W atoms are doped into the LLOs lattice via gradient doping. Experimental results and theoretical calculations indicate that Na and W doping stabilizes the crystal structure and enhances the Li + ions diffusion rate. The prepared single-crystal LLOs exhibit outstanding capacity retention of 82.7% (compared to 65.0%, after 200 cycles at 1 C) and a low voltage decay rate of 0.76 mV per cycle (compared to 1.80 mV per cycle). This strategy provides a novel pathway for designing the next-generation high-performance cathode materials for Lithium-ion batteries (LIBs)., (© 2023 Wiley‐VCH GmbH.)