Ultra Lightweight Research Articles

Enhanced EMI Shielding Efficiency of Graphene Nanoplatelets and Glass Sphere Composite‐Loaded Ultralight Weight Flexible Polyurethane Foam

ABSTRACTGraphene nanoplatelets and glass sphere (GNP@GS) composite is prepared using a simple mixing process and is loaded in flexible polyurethane foam to produce ultralight weight, high‐performance, electromagnetic interference (EMI) shielding material. The presence of a glass sphere enhances the mobility of graphene nanoplatelets in a polymer matrix forming a continuous conductive network thereby achieving better electrical conductivity and enhanced EMI shielding efficiency. The electrical conductivity of the synthesized GNP@GS/PU foam composites was achieved between 5.69 × 10−8 and 13.25 × 10−4 S/cm at varying filler loading. The maximum shielding effectiveness (i.e., −24.43 dB) was found at 12 wt% GNP@GS‐loaded samples. The shielding results show that the composites have the potential to be employed as ultralight weight, flexible EM shielding materials. These materials are essential in many applications because they are good shield materials that prevent electronic equipment from electromagnetic‐interference, better heat dissipation from the device, and also flexible to support fall protection.

Ultra-low cost and high-performance paper-based flexible pressure sensor for artificial intelligent E-skin

E-skin driven by artificial intelligence algorithms enables the innovation of future technologies such as IoT, intelligent manufacturing, health monitoring and human–machine interfaces for VR/AR. Although many flexible pressure sensors have been reported, the development of sensors that combine low-cost and high performance remains a huge challenge. Herein, we propose an all-paper-based pressure sensor with water-soluble graphite functional layer and carbon interdigital electrodes obtained by friction coating and screen printing, respectively. The sensor boasts a rectangular design measuring 1 cm × 2.15 cm, with a remarkably thin profile of only 71 μm and an ultra-light weight of 6 mg, and the cost of a single sensor is extremely low. Specifically, the sensor achieved a lower detection limit of 0.98 Pa and an upper detection limit of 2000 kPa, which represents a new benchmark among paper-based pressure sensors. It demonstrated high sensitivity across various pressure ranges: 319.94 kPa−1 (0–1 kPa), 97.63 kPa−1 (1–40 kPa), 18.75 kPa−1 (40–200 kPa), and 2.72 kPa−1 (200–2000 kPa). The sensor also exhibited a rapid response and recovery time of 8 ms and 9 ms, respectively, along with excellent durability (>20,000 fatigue tests, 10,000 cycles at 2 kPa and 10,000 cycles at 100 kPa) and high pressure stability. Furthermore, the eco-friendly sensor can identify eight surface textures with a recognition accuracy of 98.33% after training with a 2D convolutional neural network (2D CNN). Finally, a portable wireless wearable device with dimensions of 38 mm × 26 mm × 14 mm and a weight of only 11.265 g has been developed for pressure recognition, breathing, pulse, and heartbeat detection.

An ultra lightweight neural network for automatic modulation classification in drone communications

Unmanned aerial vehicle (UAV)-assisted communication based on automatic modulation classification (AMC) technology is considered an effective solution to improve the transmission efficiency of wireless communication systems, as it can adaptively select the most suitable modulation method according to the current communication environment. However, many existing deep learning (DL)-based AMC methods cannot be directly applied to UAV platform with limited computing power and storage space, because of the contradiction between accuracy and efficiency. This paper mainly studies the lightweight of DL-based AMC networks to improve adaptability in resource-constrained scenarios. To address this challenge, we propose an ultra-lightweight neural network (ULNN). This network incorporates a lightweight convolutional structure, attention mechanism, and cross-channel feature fusion technique. Additionally, we introduce data augmentation (DA) based on signal phase offsets during the model training process, aimed at improving the model’s generalization ability and preventing overfitting. Through experimental validation on the public dataset RML2016.10 A, the ULNN we proposed achieves an average precision of 62.83% with only 8815 parameters and reaches a peak classification accuracy of 92.11% at SNR = 10 dB. The experimental results show that ULNN can achieve high recognition accuracy while keeping the model lightweight, and is suitable for UAV platform with limited resources.

Modular multilayered PVC gel soft actuators for novel lightweight humanoid facial robot

Electroactive multilayered poly (vinyl chloride) (PVC) gel actuators (MPGAs) have attracted increasing interest in the field of soft robotics. However, they still face problems such as relatively low contraction strain, poor durability, and robustness. Herein, we report a new modular multilayered PVC gel actuator (M-MPGA) based on stainless steel meshed electrodes. The output characteristics of the actuator were notably improved by adjusting the plasticizer content in the gel and optimizing the structural parameters of the meshed anode electrodes. The effect of the number of stacked layers on the performance of the actuator was investigated and a dynamic model was derived for the actuator modular design. Actuator modules with multidirectional degrees of actuation were established and applied to a humanoid facial robot for the first time. The developed actuator with a meshed electrode size of #60 was found to exhibit a high contraction strain of over 20 %, which is almost twice that of the traditional MPGAs with an electrode size of #100. In addition, the fabricated actuator module had a low loss rate (1.152 %), high operating bandwidth (9.7 Hz), fast response (∼45 ms), and exceptional stability (95.24 % retention at 10,000 s actuation) without any distortion of the actuation performance. Furthermore, the developed prototype humanoid facial robot demonstrated the advantages of ultralight weight (754 g), smooth facial expression, and ease of control.

β-Lactoglobulin-based aerogels: Facile preparation and sustainable removal of organic contaminants from water

Economically and efficiently removing organic pollutants from water is still a challenge in wastewater treatment. Utilizing environmentally friendly and readily available protein-based natural polymers to develop aerogels with effective removal performance and sustainable regeneration capability is a promising strategy for adsorbent design. Here, a robust and cost-effective method using inexpensive β-lactoglobulin (BLG) as raw material was proposed to fabricate BLG-based aerogels. Firstly, photocurable BLG-based polymers were synthesized by grafting glycidyl methacrylate. Then, a cross-linking reaction, including photo-crosslinking and salting-out treatment, was applied to prepared BLG-based hydrogels. Finally, the BLG-based aerogels with high porosity and ultralight weight were obtained after freeze-drying. The outcomes revealed that the biocompatible BLG-based aerogels exhibited effective removal performance for a variety of organic pollutants under perfectly quiescent conditions, and could be regenerated and reused many times via a simple and rapid process of acid washing and centrifugation. Overall, this work not only demonstrates that BLG-based aerogels are promising adsorbents for water purification but also provides a potential way for the sustainable utilization of BLG.

Self-sacrificing template synthesis of ultralight porous hydroxyapatite microtube-based ceramics for hemoglobin adsorption

Strong and porous hydroxyapatite ceramics are highly desired for biomedical materials. However, 1D hydroxyapatite crystals with enhanced bioactivity, densification, and sinterability are limited in practical application for self-agglomeration and unfavorable 3D morphology. Herein, a sacrificed template approach is developed to prepare ultralight porous hydroxyapatite microtube-based ceramics (HMTC). First, hydroxyapatite microtubes (HMTs) are self-assembled proceeding from nanowires to microtubes through a solvothermal reaction. Then, HMTs are shaped into 3D columns by using chitosan aerogel as a template and sintered at 1300 °C to obtain ultralight porous ceramics. The chitosan template considerably contributes to constructing the macro-meso-microporous architecture of HMTC, thereby benefiting the loading capacity, biomolecule migration, cell proliferation, and other biomedical applications. HMTC exhibits ultralight weight but excellent compressive resistance to bear objects weighing hundreds of times more. HMTC exhibits a high adsorption capacity (311 mg g−1) towards bovine hemoglobin (BHb) at the pH near pI by the driving force of ionic interaction and hydrophobic interaction. The adsorption kinetics and fixed-bed adsorption confirm that the physisorption process is controlled by the intraparticle diffusion of BHb. The excellent protein adsorption performance and good recyclability demonstrate the biological availability of HMTC.

Quad-module characterization with the MALTA monolithic pixel chip

The MALTA silicon pixel detector combines a depleted monolithic active pixel sensor (DMAPS) with a fully asynchronous front-end and readout. It features a high granularity pixel matrix with a 36.4 μm symmetric pixel pitch, low power consumption of <1 μW/pixel and low material budget with detector thicknesses as little as 50 μm. It achieves a radiation hardness to 100MRad TID and more than 1 × 10E15 1 MeV neq/cm2 with a time resolution of <2 ns (Pernegger et al., 2023).In order to cover large sensitive areas efficiently with a minimum of power and data connections the development of modules, comprising of up to 4 MALTA detectors, is studied.This contribution presents the beam test performance of parallel and serial powered MALTA 4-chip modules in an effort to characterize the sensor’s chip-to-chip data and power transmission and prepare the production of a first prototype of an ultra-light weight 4-chip module on a flexible circuit with next generation MALTA2 sensors.

Properties of ultra lightweight foamed concrete utilizing agro waste ashes as an alkaline activated material

In the present investigation, rice husk ash (RHA), bamboo leaf ash (BLA) and palm oil fuel ash (POFA) known as agricultural-waste materials locally available were used to produce ultra lightweight foamed concretes (ULFCs). BLA, RHA, and POFA were used as replacements for cement in ULFCs at different weight percentages of 0 %, 5 %, 10 %, 15 %, and 20 %. To achieve the target density of 350 kg/m3, cement was substituted with agricultural wastes, and a protein foaming agent was added. The properties of ULFCs were examined including, slump test, setting time, fresh density, splitting tensile, compressive and flexural strengths, thermal insulating, microstructural and transport properties, permeability and pore's structure. The experimental results demonstrated that BLA and POFA ashes significantly outperforms in terms of efficiency and improved the mechanical and transport qualities of ULFCs than RHA ash. By increasing the weight fractions of BLA, RHA, and POFA from 5 % to 20 % in ULFC mixes resulted in an improvement in slump, porosity, capillary sorption, water absorption, bulk density, intrinsic air permeability, and specific heat. The ideal results were seen in terms of compressive strength, bending strength, splitting tensile strength, and UPV when 15 % POFA and BLA, and 10 % RHA were used as substitutes for cement. The increase in weight fraction of BLA, RHA, and POFA resulted in a rise in both thermal conductivity and thermal diffusivity of ULFCs. SEM studies revealed that incorporating different agricultural wastes positively affects the pore size distribution within the microstructure decreasing with increased content of ashes related to the development of ULFCs with stronger matrix. As a result, the formulated ULFCs met the masonry strength criteria while also providing economic and environmental benefits.

A Lightweight File System Design for Unikernel

Unikernels are specialized operating system (OS) kernels optimized for a single application or service, offering advantages such as rapid boot times, high performance, minimal memory usage, and enhanced security compared to general-purpose OS kernels. Unikernel applications must remain compatible with the runtime environment of general-purpose kernels, either through binary or source compatibility. As a result, many Unikernel projects have prioritized system call compatibility over performance enhancements. In this paper, we explore the design principles of Unikernel file systems and introduce a new file system tailored for Unikernels named ULFS (Ultra Lightweight File System). ULFS provides system call services akin to those of general-purpose OS kernels but achieves superior performance and security with significantly fewer system resources. Specifically, ULFS is developed as a lightweight file system embracing Unikernel design principles. It streamlines system calls, removes unnecessary locks, and omits permission checks for multiple users, utilizing a non-hypervisor architecture. This approach significantly reduces the memory footprint of the file system and enhances performance. Through measurement studies, we assess the performance and memory requirements of various file systems from major Unikernel projects. Our findings demonstrate that ULFS surpasses several existing Unikernel file systems, including Rumpvfs, Ramfs-u, Ramfs-q, 9pfs, and Hcfs.

Ultra-light weight proppant of diatomite-reinforced poly(methyl methacrylate-co-styrene) enabling high compressive strength, heat and acid resistance toward hydraulic fracturing

The growing emphasis on environmental protection in petroleum exploitation results in a high demand for ultra-lightweight (ULW) proppants. This work involves fabricating ULW proppant utilizing suspension polymerization, in which alkyl chain decorated natural clay diatomite (Dia) is incorporated into poly(methyl methacrylate-co-styrene) (poly(MMA-co-St)). The obtained poly(MMA-co-St)/Dia composite beads exhibit a low apparent density ranging from 1.025 to 1.213 g cm−3, and show an impressively low crushing rate of 0.99 % under 52 MPa. The rigid and thermally stable Dia crosslinks with poly(MMA-co-St) matrix, which increases the network density and restricts the movement of the molecular chain, thereby enhancing both the mechanical and thermal stability of poly(MMA-co-St)/Dia. Additionally, these composite beads display minimal acid solubility and low turbidity. The exceptional mechanical and thermal stability (attributed to the reinforcement effect and thermal barrier effect of inorganic Dia, as well as the synergistic effect of the copolymerization of MMA and styrene), along with the low acid solubility and turbidity, enabling the poly(MMA-co-St)/Dia composite to replace traditional proppants and be applied in hydraulic fracturing for oil and gas exploitation.

Ultrafast transfer of low-mass payloads to Mars and beyond using aerographite solar sails

With interstellar mission concepts now being under study by various space agencies and institutions, a feasible and worthy interstellar precursor mission concept will be key to the success of the long shot. Here we investigate interstellar-bound trajectories of solar sails made of the ultra lightweight material aerographite. Due to its extremely low density (0.18kg m−3) and high absorptivity (A∼1), a thin shell can pick up an enormous acceleration from the solar irradiation. Payloads of up to 1kg can be transported rapidly throughout the solar system, e.g., to Mars and beyond. Our simulations consider various launch scenarios from a polar orbit around Earth including directly outbound launches as well as Sun-diver launches towards the Sun with subsequent outward acceleration. We use the poliastro Python library for astrodynamic calculations. For a spacecraft with a total mass of 1kg (including 720g aerographite) and a cross-sectional area of 104m2, corresponding to a shell with a radius of 56m, we calculate the positions, velocities, and accelerations based on the combination of gravitational and radiation forces on the sail. We find that the direct outward transfer to Mars near opposition to Earth results in a relative velocity of 65km s−1 with a minimum required transfer time of 26d. Using an inward transfer with solar sail deployment at 0.6AU from the Sun, the sail’s velocity relative to Mars is 118km s−1 with a transfer time of 126d, where Mars is required to be in one of the nodes of the two orbital planes upon sail arrival. Transfer times and relative velocities can vary substantially depending on the constellation between Earth and Mars and the requirements on the injection trajectory to the Sun diving orbit. The direct interstellar trajectory has a final velocity of 109km s−1. Assuming a distance to the heliopause of 120AU, the spacecraft reaches interstellar space after 5.3yr. When using an initial Sun dive to 0.6AU instead, the solar sail obtains an escape velocity of 148km s−1 from the solar system with a transfer time of 4.2yr to the heliopause. Values may differ depending on the rapidity of the Sun dive and the minimum distance to the Sun. The mission concepts presented in this paper are extensions of the 0.5kg tip mass and 196m2 design of the successful IKAROS mission to Venus towards an interstellar solar sail mission. They allow fast flybys at Mars and into the deep solar system. For delivery (rather than fly-by) missions of a sub-kg payload, for example medical supply or replenishment of essential materials, the biggest obstacle remains in the deceleration upon arrival.

Differential Fault and Algebraic Equation Combined Analysis on PICO

In modern information technology, research on block cipher security is imperative. Concerning the ultra lightweight block cipher PICO, there has been only one study focused on recovering its complete master key, with a large search space of 264, and no fault analysis yet. This paper proposes a new fault analysis approach, combining differential fault and algebraic equation techniques. It achieved the recovery of PICO’s entire master key with 40 faults in an average time of 0.57 h. S-box decomposition was utilized to optimize our approach, reducing the time by a remarkable 75.83% under the identical 40-fault condition. Furthermore, PICO’s complete master key could be recovered with 28 faults in an average time of 0.78 h, indicating a significant 237 reduction in its search space compared to the previous study. This marks the first fault analysis on PICO. Compared to conventional fault analysis methods DFA (differential fault analysis) and AFA (algebraic fault analysis), our approach outperforms in recovering PICO’s entire master key, highlighting the cruciality of key expansion complexity in block cipher security. Therefore, our approach could serve to recover master keys of block ciphers with comparably complicated key expansions, and production of more secure block ciphers could result.

Unidirectionally Structured Magnetic Phase-Change Composite Based on Carbonized Polyimide/Kevlar Nanofiber Complex Aerogel for Boosting Solar-Thermo-Electric Energy Conversion.

To realize highly efficient solar-thermo-electric energy conversion for clean electricity power generation, we have developed a new type of unidirectionally structured magnetic phase-change composite comprising a carbonized polyimide (C-PI)/Kevlar nanofiber (KNF) complex aerogel as a 3D carbon skeleton porous supporting material, CoFe2O4 nanoparticles as a magnetic additive, polyethylene glycol (PEG) as a phase-change material, and polypyrrole as a photothermal absorption coating layer. The as-fabricated C-PI/KNF complex aerogel exhibits a unidirectional microstructure, high porosity, robust skeleton frame, ultralight weight, and high thermal conductance. Featured with such unique structure and characteristics, the complex aerogel can offer an effective heat and electron transfer method to ensure highly efficient solar-thermal conversion and photothermal energy storage of the developed composite. The developed composite exhibits a high latent heat capacity of over 150 J g-1, outstanding shape stability along with a low leakage of 0.2 wt %, good thermal cycling stability, and high photothermal conversion efficiency of 84.8%. Based on the Seebeck effect, a solar thermoelectric generation system (STEGS) was constructed with the hot side coupled with the developed composite and the cold side immersed in air and ice water. Under 2.0 kW m-2 solar irradiation, the developed STEGS in ice water obtained maximum output voltage and current of 259.7 mV and 27.1 mA, respectively, which are significantly higher than those in air. The output power of the developed STEGS in an ice water environment is 50.6% higher than that in air under 4.0 kW m-2 solar irradiation. More importantly, the developed STEGS in ice water continuously generated output voltage and current for about 810 s without solar irradiation thanks to the latent heat release by the PEG component within the developed composite. In addition, the introduction of magnetic CoFe2O4 can accelerate solar-thermal conversion through periodic electron motion by the Néel relaxation or Brownian relaxation. This resulted in an increase in the maximum output voltage and current by 13.7 and 11.5%, respectively, under an alternating magnetic field as a result of the magnetism-accelerated solar-thermo-electric conversion. This study offers an innovative approach for developing PCM-based advanced functional materials for solar energy utilization in clean and sustainable electricity generation.

Ultralight, Robust, Thermal Insulating Silica Nanolace Aerogels Derived from Pickering Emulsion Templates.

Synthesis of silica aerogel insulators with ultralight weight and strong mechanical properties using a simplified technique remains challenging for functional soft materials. This study introduces a promising method for the fabrication of mechanically reinforced ultralight silica aerogels by employing attractive silica nanolace (ASNLs)-armored Pickering emulsion templates. For this, silica nanolaces (SiNLs) are fabricated by surrounding a cellulose nanofiber with necklace-shaped silica nanospheres. In order to achieve amphiphilicity, which is crucial for the stabilization of oil-in-water Pickering emulsions, hydrophobic alkyl chains and hydrophilic amine groups are grafted onto the surface of SiNLs by silica coupling reactions. Freeze-drying of ASNLs-armored Pickering emulsions has established a new type of aerogel system. The ASNLs-supported mesoporous aerogel shows 3-fold greater compressive strength, 4-fold reduced heat transfer, and a swift heat dissipation profile compared to that of the bare ASNL aerogel. Additionally, the ASNL aerogel achieves an ultralow density of 8 mg cm-3, attributed to the pore architecture generated from closely jammed emulsion drops. These results show the potential of the ASNL aerogel system, which is ultralight, mechanically stable, and thermally insulating and could be used in building services, energy-saving technologies, and the aerospace industry.

ULAF-Net: Ultra lightweight attention fusion network for real-time semantic segmentation

ULAF-Net: Ultra lightweight attention fusion network for real-time semantic segmentation

Stabilizing Lithium-Metal Host Anodes by Covalently Binding MgF2 Nanodots to Honeycomb Carbon Nanofibers.

Constructing lithiophilic carbon hosts has been regarded as an effective strategy for inhibiting Li dendrite formation and mitigating the volume expansion of Li metal anodes. However, the limitation of lithiophilic carbon hosts by conventional surface decoration methods over long-term cycling hinders their practical application. In this work, a robust host composed of ultrafine MgF2 nanodots covalently bonded to honeycomb carbon nanofibers (MgF2/HCNFs) is created through an in situ solid-state reaction. The composite exhibits ultralight weight, excellent lithiophilicity, and structural stability, contributing to a significantly enhanced energy efficiency and lifespan of the battery. Specifically, the strong covalent bond not only prevents MgF2 nanodots from migrating and aggregating but also enhances the binding energy between Mg and Li during the molten Li infusion process. This allows for the effective and stable regulation of repeated Li plating/stripping. As a result, the MgF2/HCNF-Li electrode delivers a high Coulombic efficiency of 97% after 200 cycles, cycling stably for more than 2000 h. Furthermore, the full cells with a LiFePO4 cathode achieve a capacity retention of 85% after 500 cycles at 0.5C. This work provides a strategy to guide dendrite-free Li deposition patterns toward the development of high-performance Li metal batteries.

Multiscale Interpenetrated/Interconnected Network Design Confers All-Carbon Aerogels with Unprecedented Thermomechanical Properties for Thermal Insulation under Extreme Environments.

With ultralight weight, low thermal conductivity, and extraordinary high-temperature resistance, carbon aerogels hold tremendous potential against severe thermal threats encountered by hypersonic vehicles during the in-orbit operation and re-entry process. However, current 3D aerogels are plagued by irreconcilable contradictions between adiabatic and mechanical performance due to monotonicity of the building blocks or uncontrollable assembly behavior. Herein, a spatially confined assembly strategy of multiscale low-dimensional nanocarbons is reported to decouple the stress and heat transfer. The nanofiber framework, a basis for transferring the loading strain, is covered by a continuous thin-film-like layer formed by the aggregation of nanoparticles, which in combination serve as the fundamental structural units for generating an elastic behavior while yielding compartments in aerogels to suppress the gaseous fluid thermal diffusion within distinct partitions. The resulting all-carbon aerogels with a hierarchical cellular structure and quasi-closed cell walls achieve the best thermomechanical and insulation trade-off, exhibiting flyweight density (24mg cm-3 ), temperature-constant compressibility (-196-1600 °C), and a low thermal conductivity of 0.04829W m-1 K-1 at 300 °C. This strategy provides a remarkable thermal protection material in hostile environments for future aerospace exploration.

Dually inner-porous composites with Co@C prismatic rods anchored into graphene aerogel toward superior electromagnetic wave absorbing materials

For electromagnetic wave absorbing materials, integration of excellent electromagnetic wave absorbing property in view of strong electromagnetic wave absorbing intensity and wide effective absorption bandwidth with a very low usage, and a ultralight weight into one material is still challenging. Herein, composites of Co@C@GA (CCGA: CCGA-1, CCGA-2, CCGA-3 and CCGA-4) with a dually three-dimensional (3D) and porous structure were obtained through introducing a prismatic rod shaped Co@C prepared by calcining Co-MOF-74–3D graphene aerogel (GA). At a loading of only 12 wt%, all the CCGA with a wide weight ratio of graphene oxide to Co@C (2:1, 4:3, 1:1 and 4:5) exhibit excellent electromagnetic wave absorption properties. A minimum reflection loss (RLmin) of − 70.28 dB at 12.28 GHz with the thickness of 2.913 mm for CCGA-3 and the maximum effective absorption bandwidth (EAB) of 7.12 GHz at a thickness of 2.520 mm for CCGA-4 are achieved. The low filling ratio, the high RLmin intensity, the wide EAB and the compatibility of the two components in a broad compositional range for losing electromagnetic waves are impressive. Co@C with inner-porous and prismatic rod bundles like unique morphology is confirmed to be very important and can endow CCGA with greatly enlarged interface, enhanced conductivity and proper magnetic property, leading to the effective tuning of electromagnetic property and impedance matching condition.

Understanding of EPS beads on mechanical properties and void morphology of a CO2-solidified foam concrete based on solid wastes

Two major issues of EPS doped concrete are apparent reduction in compressive strength associated with the presence of EPS-formed artificial defects and ultra-light weight related easy segregation in the mixes, even though the thermal conductivity of composites shows a satisfactory reduction. This paper presents a composite lightweight concrete by introducing EPS into a solid waste (carbide slag and quartz sand tailings) prepared industrial grade γ-C2S-based foam concrete (CFC) to partially replace foam-formed voids. Results show that the partially EPS-substituted CFC with reasonable EPS parameters (Especially 1 mm in diameter and 5 wt% in content) exhibits a notable improvement in compressive strength (24.3%) while accompanied by the reduction in sorptivity, drying shrinkage and thermal conductivity. This is attributed to the fact that the EPS can effectively improve the foam stability by delaying foam drainage velocity due to its hydrophobicity and discrete smooth surface during the pre-curing procedure, which results in a refinement of void morphology and distribution as well as the optimized interfacial transition zone (ITZ). Accompanied by the compact inner surface and optimized ITZ, leading to a lower drying shrinkage, thermal conductivity, and also a reduction in sorptivity due to the increasing of tortuous path for the capillary flow. Moreover, magnesium slag (MS) containing dicalcium silicate mineral phase is also used to prepare MS-based CFC to further reduce costs and achieve the resource utilization of solid waste and a large amount of CO2 storage, which contributes to the sustainable development of CFC.

Optimization of ultralight SiO2/TiO2 nanofibrous aerogel for high-temperature application

Nanofibrous aerogel composites have emerged as most promising materials for their high-temperature insulation in complex environments due to their ultra lightweight, high elasticity, and superior thermal performance. However, the release of particles caused by weak bond strength between nanofibers and aerogel, lead to insulation failure which presents serious challenge. This research presents, a novel approach to mitigate the particle release and significantly improve the overall performance of nanofibrous aerogel composites. The proposed method involves the preparation of particle-free nanofibrous aerogel composites through unique combination of sol-aerogel blending, electrospinning, and freeze-casting processes. The effect of particle release has been successfully eliminated by embedding TiO2 aerogel within SiO2 nanofibers even under rigorous conditions (weight loss rate less than 0.57%). Furthermore, the resulting nanofibrous aerogel composite exhibits exceptional thermal insulation properties, with a low thermal conductivity of 0.0251 W/mK at room temperature. Additionally, the proposed composite material configuration demonstrates superior infrared radiation suppression performance resulting in an infrared transmittance of 39.52%. The lamellar structure of the nanofibers aerogel is tailored to provide high compressive strength (2.2 kPa at 40% strain), exceptional cyclic fatigue resistance after 50 cycles, and temperature (−196 to 500 °C) conditions. The outstanding combination of thermal and mechanical properties exhibited by these nanofibrous aerogel composites makes them highly promising for stable thermal protection in extreme environmental conditions. These novel materials promise great potential for application in various engineering industries where reliable thermal insulation is critical.