Advanced Materials Interfaces最新文献

Layered CoO₂ is of great interest for its promising properties but is meta-stable in its bulk form. CoO₂ is synthesized by converting the quasi-1D crystal structure of bulk Ca₃Co₂O₆ via a hydrothermal treatment. The resulting nanostructures are predominantly nanoscrolls with very thin walls, which exhibit long-term stability. A detailed structural investigation reveals that the CoO₂ is found to crystallize in monoclinic form, similar to the related CaCoO₂-CoO₂ misfit structure. Individual nanoscrolls are characterized electrically and show a p-type semiconducting nature with a high current-carrying capacity of 4·10⁵ A cm⁻² and an extremely high breakdown voltage of up to 270 kV cm⁻¹. The results demonstrate the possibility to stabilize meta-stable materials in low-dimensional forms and a promising application of the nanoscrolls as interconnect in high-voltage electronic circuitry.

Large-area graphene is typically synthesized on rolled-annealed copper foils, which require transferring to other substrates for applications. This study examines large-area graphene growth on electrodeposited (ED) copper foils—used in lithium-ion batteries and printed circuit boards—via plasma-enhanced chemical vapor deposition (PECVD). It reveals that, for a set plasma power, a minimum growth time ensures full graphene coverage, leading to monolayer and then multilayer graphene, showing PECVD growth on ED copper is not self-limited. The process also beneficially modifies the ED copper substrate, like removing the surface zinc layer and changing copper grain size and orientation, thus improving graphene growth. Additionally, the study includes high-frequency scattering parameter (S-parameter) measurements in a coplanar waveguide (CPW) system. This involves graphene on a sapphire substrate with a silver electrode. The S-parameter data indicate that the CPW with graphene shows reduced insertion losses in high-frequency circuits compared to those without graphene. This underscores graphene's role in reducing insertion losses between metallic and dielectric layers in high-frequency settings, offering valuable insights for industrial and technological applications.

The use of proteins as targeting agents often requires their chemical modification for their efficient attachment to a given surface. However, no control over the protein integrity and functionality has been demonstrated to date. Chemical over-modification causes the loss of the native structure of the protein and thus limits its targeting efficiency. To preserve structural integrity, a minimal modification strategy of proteins is developed while maintaining their functionality. Apolipoprotein A1 (ApoA1) and liposomes are utilized as a nanocarrier platform. Monitoring NHS ester chemistry by time-of-flight mass spectrometry experiments, the proposed functionalization route allows the effective chemical coupling of the minimally modified ApoA1 to the surface of the liposomes via a click chemistry reaction. The stability of the modified ApoA1 is ensured by analyzing the secondary structure by circular dichroism spectroscopy and the corresponding melting point by nano differential scanning fluorimetry. Furthermore, ApoA1 attachment to the liposomes is confirmed by flow cytometry experiments. The procedure presented in this study has the potential to be easily transferred to other proteins while introducing only minimally necessary chemical modifications to be covalently attached to different drug delivery platforms. This can help to improve their targeting efficiency for future biomedical applications.

Crystallization fouling, a process where mineral scales form on surfaces, is of broad importance in nature and technology, negatively impacting water treatment and electricity production. However, a rational methodology for designing materials with intrinsic resistance to scaling and scale adhesion remains elusive. Here, guided by nucleation physics, this work investigates the effect of coating composition and surface structure on the nucleation and growth mechanism of scale on metallic heat transfer surfaces nanoengineered by large-area techniques. This work observes that on hydrophilic nanostructured copper, despite its significantly enlarged surface area compared to smooth surfaces, scale formation is substantially suppressed leading to sustained, efficient cooling performance. This work reveals the mechanism through thermofluidic modeling coupled with in situ optical characterization and show that surface bubble formation through degassing is responsible for generating local hot spots enhancing supersaturation. This work then demonstrates a scalephobic nanostructured surface which reduces the accumulated surface scale mass 3.5× and maintains an 82% higher heat transfer coefficient compared to superhydrophobic surfaces with corresponding energy conversion savings. This work not only advances the understanding of fouling mechanisms but also holds promise for practical applications in industries reliant on efficient heat transfer processes.

Extraction of graphene and graphene derivatives from non-toxic, biocompatible, eco-friendly, and biodegradable resources with a one-step production process is a challenge. This work is the first attempt at the one-step graphenization of Shellac, a biopolymer derived from natural resources, achieved using direct laser patterning. Interestingly, the process highlights substrate independence by producing reduced graphene oxide (rGO) from multiple substrates, such as glass slides, Copper (Cu) adhesive tape, and overhead projector (OHP) plastic films. The produced rGO is fully characterized, and it is found that the sheet resistance is as low as 5.4., 24.65, and 8.4 Ω Sq⁻¹. on the glass slide, OHP plastic sheet, and Cu adhesive, respectively. Moreover, developing various logos on resin-coated ceramic tiles demonstrated the possibility of patterning desired conductive rGO patterns. Furthermore, a recyclable flexible rGO/Shellac heater is fabricated to validate its electrothermal performance (117.3 °C at 9.5 V) with foldable stability. The proposed one-step substrate independent two-material fabrication will revolutionize the process, potentially replacing conventional toxic routes of graphene production.