Surface Characterization Data Research Articles

On the corrosion resistance of the CoCrFeMnNi high entropy alloys in chloride-containing sulfuric acid solutions

The electrochemical reactivity of the high entropy Cantor alloy (CoCrFeMnNi) was investigated via potentiodynamic polarization curves, electrochemical impedance spectroscopy (EIS), and surface analysis as a function of chloride content, in sulfuric acid solutions. The results revealed that corrosion mechanism of the CoCrFeMnNi alloy at the corrosion potential, is a two-step mechanism, involving one adsorbed intermediate, similar to that of pure iron in the H2SO4, and this model provided a good description of the impedance data. X-ray photoelectron spectroscopy (XPS) surface characterization and impedance data fitting revealed that chloride ions do not alter the corrosion mechanism or the thickness of the surface oxide film. Instead, they affect the corrosion resistance by changing the composition of the oxide film. Additionally, this work demonstrated that the corrosion mechanism of the CoCrFeMnNi alloy varies with the applied potential, as evidenced by impedance measurements under potentiostatic polarization. Surface observations using scanning electron microscopy (SEM) and XPS analysis provided insights into the morphology and composition of the surface oxide film at different applied potentials, explaining the observed changes in impedance.

Enhanced PFAS adsorption with N-doped porous carbon beads from oil-sand asphaltene

Highly porous carbon beads with radially aligned macrochannels were synthesized from asphaltene for wastewater treatment and water filtration purposes. The unique porous structure of these beads facilitates efficient solute diffusion and maximizes liquid accommodation capacity, thanks to the well-ordered inwardly aligned macrovoids. Additionally, N-doping was employed to enhance the beads' adsorption properties, particularly for organic and inorganic solvents. Surface characterization data revealed that N2 modification introduced new surface functionalities, likely pyridine, and amine moieties, which actively participate in the adsorption process of polyfluoroalkyl and perfluoroalkyl substances (PFAS). Although the highest adsorbed amount of up to 74 μmol g−1 was observed for the unmodified materials, it is noteworthy that achieving equilibrium required an extensive period, exceeding 300 h. Interestingly, adsorption onto N2-modified asphaltene carbon beads exhibited higher efficiency for shorter-chain PFAS, with perfluorobutanoic acid adsorbing at 66.41 μmol g−1 and perfluorooctanoic acid reaching up to 7.67 μmol g−1. Overall, the maximum adsorption capacity of all asphaltene carbon beads followed the order PFHxA < PFOA < PFBA, indicating that the length of the carbon chain in PFAS is not the sole determining factor for adsorption. This observation suggests that the modification of asphaltene carbon beads and the introduction of N2 in the form of amino groups provide additional sites for hydrogen bond formation, influencing the adsorption process. The presented results highlight the enhanced efficiency of PFAS removal achieved by utilizing sustainable materials and methods in wastewater treatment.

Electrocatalytic sensing of metronidazole by R-type hexagonal nanoferrites modified electrode

The current study was aimed to synthesize the R-type hexagonal nanoferrites (SrSn2Fe4O11) for electrochemical sensing of metronidazole (MN) in pharmaceutical and human specimen. The SrSn2Fe4O11 were prepared by sol-gel auto ignition method followed by structural and surface characterization by X-Ray diffraction (XRD) and atomic force microscopy (AFM) respectively. The resulting surface characterization data suggested that the synthesized SrSn2Fe4O11 have a single-phase crystalline structure with a crystalline size of 34.451 nm with surface topographical ranging from 0.506 to 3.37 nm. The SrSn2Fe4O11 modified glassy carbon electrode (SrSn2Fe4O11/GCE) was fabricated by a drop-casting method. The fabricated SrSn2Fe4O11/GCE was successfully applied for detecting MN in a phosphate buffer (PB) at pH-6, followed by a linear voltammetric response with the coefficient of determination (R2 = 0.998). The limit of detection and quantification (LOD/LOQ) for sensing MN was found to be 0.011 to 0.036 μM, respectively. A differential pulse voltammetric study of MN on SrSn2Fe4O11/GCE demonstrated a significant selectivity with RSD 2.0%. The proposed electrochemical method was successfully applied for the quantitative detection of MN in pharmaceutical preparations and biological specimen.

Natural light-trapping nanostructures on thermally-grown cupric oxide

Thermal oxidation of copper produces a layer of copper oxides. We present results showing that the surface of this thermal oxide naturally has an involuted morphology that can trap a very significant amount of incident radiation (∼70–90%). This phenomenon is of particular interest at near-infrared and visible wavelengths where the oxide shows band gap absorption. We provide details on the growth process and surface characterization data, including SEM micrographs, surface reflection spectra, as well as diffuse reflection measurements. These reveal the intricate surface morphology and its effect on light trapping and scattering from the oxide surface.

Surface-Active Plasma-Polymerized Nanoparticles for Multifunctional Diagnostic, Targeting, and Therapeutic Probes

Surface-functionalized polymeric nanoparticles have advanced the field of nanomedicine as promising constructs for targeted delivery of molecular cargo as well as diagnostics and therapeutics. Conventionally, the functionalization of polymeric nanoparticles incorporates tedious wet chemical methods that require complex, multistep protocols. Surface-active plasma-polymerized nanoparticles (PPNs) produced by a dry, low-pressure plasma process can be easily functionalized with multiple ligands in a simple step. However, plasma polymerization remains limited by the challenge of efficient collection of PPNs from low-pressure plasma reactors. Here, we demonstrate a simple method to overcome this limitation by delaying the inflow of the polymer-forming precursor gas, acetylene, into a nitrogen and argon plasma discharge. We provide evidence that this cutting-edge development in the plasma polymerization method drastically enhances the collection yield of nanoparticles by 2.5-fold, compared to the simultaneous inflow of the gases. COMSOL Multiphysics simulations support our experimental data and provide insights into the role of pressure gradients in regulating the forces controlling the collection of the particles. Surface characterization data revealed that changing the sequence of the precursor gas inflow had no significant effect on the physicochemical properties of the nanoparticles, as critically important for theranostic applications. A model, green fluorescent protein, was successfully conjugated to the surface of the PPNs via a reagent-free, one-step incubation process that immobilized the biomolecule while retaining its biological activity. Cytotoxicity of the particles was assessed by a lactate dehydrogenase (LDH) assay at concentrations of up to 5 × 105 nanoparticles per cell. Despite their high concentrations, the nanoparticles were remarkably well tolerated by the cells, demonstrating their superb potential for in vivo cellular uptake. This study advances previous research on plasma-polymerized nanoparticles, introducing a low-waste synthesis method that achieves higher yields. This sustainable technology has important implications for the production of multifunctional nanoparticles for drug delivery, tumor targeting, and medical imaging.

Hip implant modular junction: The role of CoCrMo alloy microstructure on fretting-corrosion

Cobalt-chromium-molybdenum (CoCrMo) alloy is one of the most used metals in total hip replacement (THR) due to the alloy's superior corrosion qualities and biocompatibility. Over time these prostheses may undergo wear and corrosion processes in a synergistic process known as tribocorrosion. Implant retrieval studies have shown that damage patterns on THR modular junction surfaces indicating specifically in vivo fretting-corrosion to take place. To date, there have been no studies on the fretting-corrosion behaviors of CoCrMo alloy under the consideration of specific microstructural features. A custom-built flat-on-flat fretting-corrosion setup was utilized to test the synergistic tribocorrosion behavior of fretting-corrosion. The difference in microstructure was generated through the cutting orientations of the transverse and the longitudinal direction of the bar stock material, where the longitudinal cut exhibits a characteristic banded microstructure (banded group) and the transverse cut a homogenous microstructure (unbanded group). A three-electrode system was employed to monitor the induced currents. Two different types of electrolytes were used in the current study: 1. Bovine calf serum (BCS-30 g/L protein) (normal conditions) 2. BCS with Lipopolysaccharide (LPS, 0.15 μg/ml) (simulated infectious conditions). In the free potential mode, banded samples showed an increased potential compared to the unbanded samples. In potentiostatic conditions, the banded group also exhibited a higher induced current in both electrolyte environments, indicating more corrosion loss. Both Nyquist and Bode plots showed both orientations of metal becoming more corrosion resistant post-fretting when compared to pre-fretting data. The longitudinal group at OCP demonstrated a unique shape of the fretting-loop, which might be related to tribochemical reactions. Based on the mechanical, electrochemical, and surface characterization data, the transverse group (unbanded) microstructures demonstrates a higher resistance to fretting-corrosion damage.

Robust silane self-assembled monolayer coatings on plasma-engineered copper surfaces promoting dropwise condensation

Dropwise condensation is well known to result in better heat transfer performance owing to efficient condensate/droplet removal, which can be harnessed in various industrial heat/mass transfer applications such as power generation and conversion, water harvesting/desalination, and electronics thermal management. The key to enhancing condensation via the dropwise mode is thin low surface energy coatings (<100 nm) with low contact angle hysteresis. Ultrathin (<5 nm) silane self-assembled monolayers (or SAMs) have been widely studied to promote dropwise condensation due to their minimal thermal resistance and scalable integration processes. Such thin coatings typically degrade within an hour during condensation of water vapor. After coating failure, water vapor condensation transitions to the inefficient filmwise mode with poor heat transfer performance. We enhance silane SAM quality and durability during water vapor condensation on copper compared to state-of-the-art silane coatings on metal surfaces. We achieve this via (i) surface polishing to sub-10 nm levels, (ii) pure oxygen plasma surface treatment, and (iii) silane coating integration with the copper substrate in an anhydrous/moisture-free environment. The resulting silane SAM has low contact angle hysteresis (≈20°) and promotes efficient dropwise condensation of water for >360 hours without any visible sign of coating failure/degradation in the absence of non-condensable gases. We further demonstrate enhanced heat transfer performance (≈5-7× increase over filmwise condensation) over an extended period of time. Surface characterization data post-condensation leads us to propose that in the absence of non-condensable gases in the vapor environment, the silane SAM degrades due to reduction and subsequent dissolution of copper oxide at the oligomer-substrate interface. The experiments also indicate that the magnitude of surface subcooling (or condensation rate) affects the rate of coating degradation. This work identifies a pathway to durable dropwise promoter coatings that will enable efficient heat transfer in industrial applications.

Predictive model for bearing torque in bolt fastening

Quality control in automated bolt fastening is challenging due to the variance in appropriate tightening torque from sample to sample. This study presents an algorithm based on contact mechanics theories that predicts the bearing torque at the bolt underhead according to the surface morphology, RMS height, and hardness. The model identifies the key surface parameters to be analyzed and the predictive algorithm quantitatively calculates the frictional torque with the known surface characterization data. Different combinations of bolts and plates with a range of surface properties were tested for experimental validation, which confirms 95.3∼99.0% of accuracy of the predictive model.

Persimmon peel-based ion-imprinted adsorbent with enhanced adsorption performance of gallium ions

A gallium ion-imprinted material (Ga-IIP-PP) was fabricated from persimmon peel using persimmon tannin as a functional monomer. Thereafter, it was applied for the selective adsorption of Ga ions from aqueous solutions containing other metal ions. The sorbent morphology and surface characterization data confirmed the successful loading of a gallium-imprinted layer onto the waste persimmon peel. The imprinted material exhibited a relatively smooth structure with few wrinkles, a negatively charged surface, and a low number of hydroxyl surface functional groups. The results of adsorption experiments revealed that Ga-IIP-PP could be applied in a wide range of Ga concentrations, while its highest adsorption capacity of 128 mg/g and adsorption rate of 0.0081 min−1 were achieved at pH = 3. Moreover, the synthesized Ga-IIP-PP exhibited high selectivity toward Ga ions even in binary systems with similar competitive ions. Finally, Fourier-transform infrared spectroscopy and X-ray photoelectron spectroscopy were performed to elucidate the adsorption mechanism of Ga ions onto the Ga-IIP-PP surface, which primarily involved electrostatic adsorption and the cation exchange between the H+ ions of OH/COOH groups and Ga ions. This work demonstrates that the bio-sorbent prepared from waste persimmon peel is a promising adsorbent for recovering Ga ions from aqueous solutions.

Selective atomic layer etching of HfO2 over silicon by precursor and substrate-dependent selective deposition

The early work of John Coburn and Harold Winters revealed a synergistic effect in ion-enhanced Si etching by the concurrent irradiation of Ar+ and XeF2. This finding provided an important foundation for the development of plasma dry etching processes. The experimental results of Coburn and Winters also found effects that are useful for the development of atomic layer etching (ALE) processes characterized by a self-limited etch rate. ALE approaches are widely established and can be utilized in either directional or isotropic etching by employing proper surface modification and product removal steps. Nevertheless, the development of material selective ALE processes is still limited. An approach that combines substrate-selective deposition with etching opens a new processing window for selective ALE. The authors studied the deposition behavior of mixtures of methane (CH4) with trifluoromethane (CHF3) and mixtures of methane with octafluorocyclobutane (C4F8) on HfO2 and Si surfaces. The experimental results show that a CH4/C4F8 mixture produces a comparable fluorocarbon (FC) deposition thickness on both HfO2 and Si during the deposition step. In contrast, a CH4/CHF3 mixture deposits an FC film on Si, whereas it fluorinates the HfO2 surface with negligible FC deposition. Utilizing these behaviors allows for an ALE process based on CH4/CHF3 for selective removal of HfO2 over Si. Surface characterization data that provide mechanistic insights into these processes are also provided and discussed.

The Effect of Surface Treatment on the Performance of a Trivalent Chromium Process (TCP) Pretreatment on AA7075 Aerospace Alloys for the Protection Against Filiform Corrosion

The performance of a trivalent chromium process (TCP) pretreatment conversion coating, applied to AA7075 aerospace aluminum alloys, for its ability to improve the filiform corrosion (FFC) of a polyvinyl-butyral coating, was studied as a function of surface treatment. Data from atmospheric FFC and full-immersion corrosion experiments are compared with surface characterization data to gain an understanding of the FFC kinetics on this alloy and mechanism by which the TCP coating provides inhibition. Specimens were prepared with three different surface treatments and studied with and without a TCP pretreatment conversion coating. A biphasic layer incorporating a zirconium-chromium mixed oxide outer layer and a fluoroaluminate interfacial layer was observed on all pretreated specimens. Enhanced corrosion protection by the TCP coating was observed when an acid pickle surface treatment was applied and the FFC filament propagation was stifled with an efficiency of 86%. A zirconium-rich outer oxide layer of approximately 22 nm, more than double the thickness of that measured for the other surface-treatments, is reported. Such layers are reported to be sufficiently dense so as to block ion transport from solution to the alloy surface. This acid pickle surface treatment is shown to effectively reduce the thickness of the native oxide layer and remove intermetallic particles from the surface enabling the formation of a more homogeneous TCP layer. Furthermore, Cu replating resulting from an acidic deoxidation step is shown to have no discernable effect on FFC.

Removal of a potentially hazardous chemical, tetrakis (hydroxymethyl) phosphonium chloride from water using biochar as a medium of adsorption

Abstract The research investigates the efficiency of biochar to eliminate an emerging contaminant, flame retarding chemical, a.k.a. Tetrakis (Hydroxymethyl) Phosphonium Chloride (THPC) from water. The THPC, which is a water-soluble, organophosphorus salt, is mainly used by textile industries as a flame retardant and crease resistant for cotton and cellulose fabrics. Our research explores the possible removal process of THPC from water while using biochar as a mode of adsorption. Commercial biochar was used to investigate the adsorption efficiency of THPC. Spectroscopic and surface characterization data were provided for the commercial biochar. Study showed the presence of several organic functional groups on biochar which have potential to contribute to an efficient adsorption process. Batch adsorption studies were conducted varying several parameters like biochar dosages, contact time of the substrate to biochar, agitation time, and temperature during the experiment. It was found that benign experimental conditions such as lower biochar dosage, lower temperature and lower agitation time maximized the adsorption capacity. Furthermore, biochar was chemically treated with various activation agents and the removal efficiency was compared between activated and non-activated biochar. It was found that chemical activation on biochar indeed improved the THPC removal efficiency. Results also indicates that the adsorption mechanism of THPC on to biochar surface followed both Langmuir and Freundlich isotherms. Finally, it was observed that the adsorption process was fitted best with pseudo-second-order kinetic model which might indicate a possible chemisorption mechanism for the adsorption of THPC on biochar surface.

Characterizing Surfaces of Garnet and Steel, and Adsorption of Organic Additives.

This work reports that abrasive blasting of a structural steel results in significant retention of garnet abrasive residues. A comparative study of the adsorption behavior of a number of organic species, relevant to paint components and additives, onto the surfaces of garnet and S355 steel from nonaqueous solutions is also presented. Areas per adsorbed molecule, estimated from the isotherm data, suggest a range of molecular orientations on the surfaces. Pronounced differences in the adsorption strength to the garnet and steel were observed, particularly that most additives bind more strongly to steel than to garnet. Surface characterization data from acid-base titrations, photoelectron spectroscopy, and backscattered electron diffraction were used to rationalize the adsorption data obtained. The ramifications of these findings for particular industrial processes, with regards the strength of paint adhesion and paint additive formulations, are highlighted.

Determination of rotational and vibrational temperatures of CH in CH4 plasmas

Understanding fundamental plasma–surface interactions remains an important component of increasing the utility of plasma systems in a range of applications including plasma-assisted catalysis (PAC). A key element in realizing the potential of these applications is understanding the foundational data that control the overall process. Here, fundamental gas-phase and film chemistry trends in methane inductively coupled plasmas are studied to model PAC systems for decomposition of volatile organic compounds. Specifically, energy partitioning trends are presented in conjunction with surface characterization data to elucidate processes occurring at the plasma–surface interface. Optical emission spectroscopy yields rotational and vibrational distribution measurements that can be converted to temperatures (TR and TV) for CH in 100% CH4 and CH4/Ar plasmas as a function of pressure (50–200 mTorr) and applied rf power (25–150 W). Under these conditions, TV ranges from ∼3000 to ∼5000 K, whereas TR has values of 1500–2500 K. These are considerably above room temperature, even at pressures of 200 mTorr and Ar content as high as 25% of total precursor feed. Surface characterization of plasma-treated substrates yields minimal changes in chemical composition but more significant variations in film morphology as functions of plasma pressure and applied rf power. Collectively, these data aim to unravel the complex chemistry of plasma systems for PAC.

Secrets of Plasma-Deposited Polyoxazoline Functionality Lie in the Plasma Phase

Plasma deposited polyoxazoline thin films share many valuable properties with polyoxazoline prepared via conventional organic chemistry; they are biocompatible, non-cytotoxic and low fouling. What is more, they bind biomolecules covalently, support cell adhesion, and are generated in a solvent free, single step process. Here, we show that the secret for plasma deposited polyoxazolines’ unique set of properties lies in both the chemical fragmentation processes occurring in the plasma phase itself and the recombination events subsequently occurring at the plasma-activated surface. In situ plasma mass spectroscopy was used to elucidate the complex composition of the oxazoline plasma phase at nominal powers ranging from 2 to 50W. This confirmed the stability of the un-opened monomer, but also revealed the formation of nitrile, isocyanate, and imine species. In correlation with post-plasma surface characterization data, the mass spectroscopy results indicate that reactive functional groups were plasma-generate...

Noncovalent immobilization and surface characterization of lanthanide complexes on carbon electrodes.

A new tripodal ligand featuring three appended pyrene moieties has been prepared for studies of noncovalent binding of lanthanide metal complexes to graphitic carbon surfaces. The ligand tightly binds lanthanide(iii) ions by encapsulation within a heptadentate coordination environment; the cerium, neodymium, samarium, and europium complexes (all with formal metal oxidation state of +3) have been synthesized and characterized. These compounds are readily immobilized on graphitic electrodes-this is driven by the presence of the pyrene moieties, as complexes of an analogous ligand without pyrene groups are not stably adherent to the surface. X-ray photoelectron spectra confirm the molecular identity of the pyrene-appended metal complexes upon immobilization, with unique signals appearing for the metal centers as well as all for all symmetry-related nitrogen atoms on the ligand. Consistent with these surface characterization data and studies of a soluble model compound, the surface-immobilized cerium(iii) complex is reversibly oxidized to cerium(iv) near -0.34 V vs. Fc+/0. Based on electrochemical data, this complex is stable for minutes to hours on the surface.

Superamphiphobic surfaces constructed by cross-linked hollow SiO2 spheres

By using stringed carbon spheres as template material, a series of hierarchical 3D cross-linked SiO2 coated carbon spheres and hollow SiO2 spheres were fabricated, and spray-coated on glass slides, followed by the fluorination treatment with per-fluorotrichlorosilane. The surface characterization and surface wettability data indicated that hollow SiO2 spheres spray-coated surfaces showed better superhydrophobicity and superoleophobcity properties than the corresponding solid C@SiO2 coated surface. This study further demonstrated that superamphiphobicity depends on two critical factors, namely a cavity- and spot-rich hierarchical structure and the size and shape of overhangs. Moreover, the optimal conditions for the preparation of hollow SiO2 coated glass slide were identified after a systematic investigation of various concentrations of the carbon precursor and tetraethylorthosilicate. It was found that when 0.10g carbon spheres prepared from 1.0M carbon precursor were used as the template and 20mg/mL tetraethylorthosilicate was used as silica precursor, the hollow SiO2 coated glass slide exhibited the best superamphiphobic performance, with the highest contact angles and lowest sliding angles for various liquids, such as water, olive oil, n-hexadecane and n-dodecane.

Modified surface morphology of a novel Ti–24Nb–4Zr–7.9Sn titanium alloy via anodic oxidation for enhanced interfacial biocompatibility and osseointegration

The Ti–24Nb–4Zr–7.9Sn titanium alloy (Ti2448) has shown potential for use in biomedical implants, because this alloy possesses several important mechanical properties, such as a high fracture strength, low elastic modulus, and good corrosion resistance. In this study, we aimed to produce a hierarchical nanostructure on the surface of Ti2448 to endow this alloy with favorable biological properties. The chemical composition of Ti2448 (64.0wt% Ti, 23.9wt% Nb, 3.9wt% Zr, and 8.1wt% Sn) gives this material electrochemical properties that lead to the generation of topographical features under standard anodic oxidation. We characterized the surface properties of pure Ti (Ti), nanotube-Ti (NT), Ti2448, and nanotube-Ti2448 (NTi2448) based on surface morphology (scanning electron microscopy and atomic force microscopy), chemical and phase compositions (X-ray diffraction and X-ray photoelectron spectroscopy), and wettability (water contact angle). We evaluated the biocompatibility and osteointegration of implant surfaces by observing the behavior of bone marrow stromal cells (BMSCs) cultured on the surfaces in vitro and conducting histological analysis after in vivo implantation of the modified materials. Our results showed that a hierarchical structure with a nanoscale bone-like layer was achieved along with nanotube formation on the Ti2448 surface. The surface characterization data suggested the superior biocompatibility of the NTi2448 surface in comparison with the Ti, NT, and Ti2448 surfaces. Moreover, the NTi2448 surface showed better biocompatibility for BMSCs in vitro and better osteointegration in vivo. Based on these results, we conclude that anodic oxidation facilitated the formation of a nanoscale bone-like structure and nanotubes on Ti2448. Unlike the modified titanium surfaces developed to date, the NTi2448 surface, which presents both mechanical compatibility and bioactivity, offers excellent biocompatibility and osteointegration, suggesting its potential for use in orthopedic applications.

Surface Characterization and Platinum-like Electrocatalytic Activity of Nano-Scale Platinum Deposited on Transition Metal Carbide Nanotubes via Atomic Layer Deposition

This work focuses on a new class of electrocatalyst fabrication in which phase pure β-molybdenum carbide (referred to as Mo2C hereafter) was synthesized into hollow nanotubes and subsequently modified with nanoscale platinum (Pt) particles (1-5 nm) deposited via rotary Atomic Layer Deposition (ALD) (referred to as Pt/Mo2C). Pt has been deposited on Mo2C with 15, 50 and 100 ALD cycles. Strong interaction between Pt and Mo2C was observed by XPS and HRTEM. In this paper, we focus on presenting comparison of eletrochemical and surface characterization data among three ALD cycles (100, 50 and 15) to elucidate how performance of the resulting co-catalyst can be tuned by the easily tunable ALD process parameter, number of ALD cycles.

Geophysical controls on C band polarimetric backscatter from melt pond covered Arctic first‐year sea ice: Assessment using high‐resolution scatterometry

Geophysical controls on C band polarimetric backscatter from the discrete surface cover types which comprise advanced melt first‐year sea ice (FYI): snow covered ice, bare ice, and melt pond; are assessed using polarimetric radar scatterometry from test sites representing high Arctic and marginal ice zones in the Canadian Arctic. Surface characterization data is used to evaluate the interaction of polarized radiation with each feature, and dominant scattering mechanisms are assessed in a regional context. High‐resolution time series (diurnal) scatterometry and coincident atmospheric boundary layer profile data are used to explain linkages between ice‐atmosphere interactions and polarimetric backscatter in a marginal ice zone. The co‐polarization ratio for FYI melt ponds is shown to be distinct from snow covered ice or bare ice during early and peak phases of advanced melt, making it a candidate parameter for the unambiguous detection of pond formation and the inversion of melt pond fraction. The ratio displays an increasing trend with radar incidence angle in a manner consistent with Bragg surface scattering theory, though it is not predictable by a Bragg model. Cross‐polarization backscatter intensity shows potential for discriminating the onset and duration of freeze events in a marginal ice zone, due to dominant backscatter from the snow cover adjacent to melt ponds. Preliminary results here outline the potential of covariance matrix derived polarimetric measurements for the inversion of advanced melt sea ice geophysical parameters, and provide a basis for the investigation of distributed targets in late season spaceborne polarimetric SAR scenes.