High-temperature-resistant, high-strength, and lightweight multifunctional aerogels are urgently required for critical thermal management in harsh conditions, but balancing many factors is highly difficult. Zirconium carbide nanowires (ZrCnws) have received increasing attention due to their exceptional high-temperature stability. In this work, ZrCnws aerogels were prepared by freeze-drying and heat treatment methods without metal catalysts. The single ZrCnw shows a cylindrical structure with a smooth surface. The growth of ZrCnws relied on S-L-S mechanism. ZrCnws aerogels have a density of approximately 24.38 mg/cm 3 and low thermal conductivity of 33.8 mW/(m•K) at room temperature. ZrCnws aerogels have 74.88% height retention after 100 cycles of compression at 30% strain and exhibit a specific EMI SE of 1458.61 dB•cm 3 •g −1 in the X band. This work provides a feasible method for ZrCnws aerogels and verifies that the prepared ZrCnws aerogels have potential applications in the fields of thermal insulation and electromagnetic shielding.
Undoubtedly, taking full advantage of near-infrared light (NIR) for the photocatalytic reaction is a promising way to realize the efficient utilization of solar energy. In this work, zirconium carbide (ZrC) has been exploited as a NIR-driven photoactive substance for the simultaneous photodegradation of organic pollutants and photothermal sterilization of Escherichia coli ( E. coli ). The metallic nature and NIR-responsive localized surface plasmon resonance (LSPR) behaviors of ZrC are revealed by both experimental evidence and density function theory (DFT) calculations. ZrC exhibits extremely wide spectral absorbance, excellent NIR-triggered photosensitive effect and photothermal conversion efficiency. Activation kinetics was performed with DFT to investigate the activation process of O 2 to •O 2 – . In addition, a possible NIR-mediated photocatalytic mechanism of ZrC was proposed on the basis of above DFT simulation and radical scavenging experiments. Metallic ZrC with NIR-responsive activity provides a new perspective for designing full-spectrum-driven photocatalysts.
Nanocrystallized zirconium carbide (ZrC) powder was synthesized by an aqueous solution-based process using zirconium acetate and sucrose as starting reagents. Polyvinyl pyrrolidone (PVP) was used to combine the reactants to form a suitable precursor for ZrC. Through such a novel aqueous solution-based process, fine-scale mixing of the reactants is achieved in an environmentally friendly manner. The formed precursor can be converted to ZrC by carbothermal reduction reaction at 1600–1650 °C. Thanks to a limited amount of residual free carbon, the as-synthesized ZrC powder had an ultra-fine particle size (50–100 nm) and a low oxygen content less than 1.0 wt%. The conversion mechanisms from as-synthesized pre-ceramic precursor to ZrC powder were investigated systematically and revealed by means of FTIR, TG-DSC, XRD, Raman, SEM and TEM.
Traditional surface-enhanced Raman scattering (SERS) substrates typically rely on electromagnetic enhancement, which is predominantly generated by noble metal particles. While their practical limitations hinder widespread application. In contrast, semiconductor substrates have garnered increasing attention in the SERS field due to their capacity to address many of the shortcomings associated with noble metal particles. In this study, we investigated the SERS effect and enhancement mechanism of a novel transition metal carbide (ZrC), further enhancing its performance through morphological alterations and element doping. The detection limits for Rhodamine 6G and Methylene blue using the prepared substrate were found to be remarkably low at 1 × 10 -8 M and 1 × 10 -6 M. To elucidate the enhancement mechanism, Density Functional Theory and Finite Element Analysis were employed. These simulations demonstrated that the observed enhancement arises from chemical mechanisms. The charge transfer process between the SERS substrate and the probe molecule resulted in significantly amplified Raman signals.
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