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1. High strength and damage-tolerance in echinoderm stereom as a natural bicontinuous ceramic cellular solid

   https://doi.org/10.1038/s41467-022-33712-z  

   Yang, Ting; Jia, Zian; Wu, Ziling; Chen, Hongshun; Deng, Zhifei; Chen, Liuni; Zhu, Yunhui; Li, Ling (December 2022, Nature Communications)

   Abstract Due to their low damage tolerance, engineering ceramic foams are often limited to non-structural usages. In this work, we report that stereom, a bioceramic cellular solid (relative density, 0.2–0.4) commonly found in the mineralized skeletal elements of echinoderms (e.g., sea urchin spines), achieves simultaneous high relative strength which approaches the Suquet bound and remarkable energy absorption capability (ca. 17.7 kJ kg⁻¹) through its unique bicontinuous open-cell foam-like microstructure. The high strength is due to the ultra-low stress concentrations within the stereom during loading, resulted from their defect-free cellular morphologies with near-constant surface mean curvatures and negative Gaussian curvatures. Furthermore, the combination of bending-induced microfracture of branches and subsequent local jamming of fractured fragments facilitated by small throat openings in stereom leads to the progressive formation and growth of damage bands with significant microscopic densification of fragments, and consequently, contributes to stereom’s exceptionally high damage tolerance. 

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2. Germanium‐Functionalized 3D Microporous, Nanostructured Nickel–Nickel Oxides for Application in Asymmetric Supercapacitors

   https://doi.org/10.1002/ente.202300360  

   Kr_Singh, Balwant; Das, Debabrata; Gonzalez, Cristina; Ramana, C V (October 2023, Energy Technology)

   Supercapacitors and batteries are essential for sustainable energy development. However, the bottleneck is the associated high cost, which limits bulk use of batteries and supercapacitors. In this context, realizing that the cost of energy‐storage device mainly depends on materials, synthesis processes/procedures, and device fabrication, an effort is made to rationally design and develop novel low‐cost electrode materials with enhanced electrochemical performance in asymmetric supercapacitors. Herein, surface functionalization approach is adopted to design low‐cost 3D mesoporous and nanostructured nickel–nickel oxide electrode materials using facile synthesis for application in supercapacitors. It is demonstrated that the 3D mesoporous Ni provides the high surface area and enhanced ionic conductivity, while germanium functionalization improves the electrical conductivity and reduces the charge‐transfer resistance of NiO. Surface functionalization with Ge demonstrates the significant improvement in specific capacitance of NiO. The asymmetric supercapacitor using these Ge‐functionalized NiO–Ni electrodes provides a specific capacitance of 304 Fg⁻¹(94 mF cm⁻²), energy density of 23.8 Wh kg⁻¹(7.35 μWh cm⁻²), and power density of 6.8 kW kg⁻¹(2.1 mW cm⁻²) with excellent cyclic stability of 92% after 10 000 cycles. To validate their practical applications, powering the digital watch using the asymmetric supercapacitors in laboratory conditions is demonstrated. 

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3. Engineering of high specific strength and low thermal conductivity cementitious composites with hollow glass microspheres for high-temperature high-pressure applications

   https://doi.org/https://doi.org/10.1016/j.cemconcomp.2020.103514  

   Krakowiak, K. J. (April 2020, Cement concrete composites)

   Lightweight cement-based composites with high specific strength and low thermal conductivity are highly sought in the energy and construction industries. These characteristics are important in designing cement liners for high-temperature, high-pressure (HTHP) wells, in addition to those operating in permafrost. Similar attributes are also desirable in designing cementitious composites for energy efficient building envelopes. This work reports the results of an experimental campaign focused on engineering lightweight cementitious composites with hollow glass microspheres. It is demonstrated that the chemical stability of microspheres at HTHP conditions can be directly controlled by modulating the specific surface area and dissolution rate constant of supplementary siliceous additives. In addition to the stabilizing effect, such additives lead to the pore structure refinement and the enhancement of interfacial transition zone (ITZ). Introduced lightweight composites are capable of delivering significant load bearing capacity when normally cured, which is greatly increased by hydrothermal curing. Such high specific strength composites possess thermal conductivity below 0.3 W/mK at the oven dry density <1000 kg/m3 and cement dosage <400 kg/m3. This class of cementitious composites bears potential to enhance zonal insulation and well integrity, as well as increasing energy efficiency of building envelopes. 

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4. Recent Advances in the Synthesis of Polymer-Grafted Low-K and High-K Nanoparticles for Dielectric and Electronic Applications

   https://doi.org/10.3390/molecules26102942  

   Tawade, Bhausaheb V.; Apata, Ikeoluwa E.; Pradhan, Nihar; Karim, Alamgir; Raghavan, Dharmaraj (May 2021, Molecules)

   null (Ed.)

   The synthesis of polymer-grafted nanoparticles (PGNPs) or hairy nanoparticles (HNPs) by tethering of polymer chains to the surface of nanoparticles is an important technique to obtain nanostructured hybrid materials that have been widely used in the formulation of advanced polymer nanocomposites. Ceramic-based polymer nanocomposites integrate key attributes of polymer and ceramic nanomaterial to improve the dielectric properties such as breakdown strength, energy density and dielectric loss. This review describes the ”grafting from” and ”grafting to” approaches commonly adopted to graft polymer chains on NPs pertaining to nano-dielectrics. The article also covers various surface initiated controlled radical polymerization techniques, along with templated approaches for grafting of polymer chains onto SiO2, TiO2, BaTiO3, and Al2O3 nanomaterials. As a look towards applications, an outlook on high-performance polymer nanocomposite capacitors for the design of high energy density pulsed power thin-film capacitors is also presented. 

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5. The role of polymer coatings in lipid membrane penetration by graphene oxide dots

   https://doi.org/10.1039/D5NR00838G  

   Frigerio, Giulia; Siani, Paulo; Donadoni, Edoardo; Cui, Qiang; Di_Valentin, Cristiana (August 2025, Nanoscale)

   Understanding the cell membrane penetration process of biomedical nanosystems and its dependence on nanomaterial properties and surface functionalization is crucial for the rational design of safe and efficient cellular internalization strategies. Computer simulations are powerful tools to evaluate the thermodynamic aspects of the process and to elucidate its underlying molecular mechanisms. In this work, the interaction between uncoated or polymer-coated graphene oxide (GO) dots and lipid bilayer models is investigated by coarse-grained (CG) molecular dynamics (MD) simulations. We first validate the coarse-grained model against all-atom MD simulations (AAMD). Then, we perform CGMD simulations and free energy calculations to assess the effect of the polymeric coating and of its features (grafting density, polymer end-group charge and polymer hydrophilic/hydrophobic character) on the interaction between GO dots of realistic size and lipid membranes. We find that the membrane penetration of GO dots is spontaneous when coated with a low-density polyethylene glycol (PEG) layer, while a high-density PEG coating prevents the penetration, and a mixed PEG/polyethylene (PE) coating excessively stabilizes the nanosystem in the inner membrane region. These findings will help to fine-tune how GO dots interact with cellular membranes. 

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