Aqueous Zn batteries are sustainable energy storage devices that gained considerable research interest over the last few years. Positive electrode materials are commonly coated onto current collectors which need to remain electrochemically and chemically stable during the battery lifespan. Herein, we report on the electrochemical stability of aluminum current collector in mild acidic zinc electrolytes, 1 M ZnSO4 and 1 M Zn(CF3SO3)2 (known as Zn- triflate). The aluminum foil underwent severe anodic oxidation (commonly referred to as corrosion) upon the 1st anodic oxidation cycle at a scan rate of 5.0 mV s − 1 in Zn-triflate electrolyte. On the contrary, the aluminum foil did not feature signs of corrosion in 1 M ZnSO4 electrolyte over ~200 cycles of cyclic voltammetry at a scan rate of 5.0 mV s − 1 . The foil surface was found to be passivated by the growth of a surface oxide layer, as confirmed by XPS, EDX and SEM analyses. At a lower scan rate of 0.5 mV s − 1 , the aluminum corrosion was observed over 100 cycles, suggesting the local pH at the electrode surface at low scan rate can result in dissolving the aluminum foil. The use of concentrated electrolyte, 2 M ZnSO4, and/or coating the aluminum surface with a carbon layer did not efficiently mitigate the aluminum corrosion during long-term cycling. This work opens a venue for understanding the challenges of using aluminum current collectors in mild acidic Zn electrolytes.

Replacing petroleum-based with bio-based ingredients in articles and chemical products is one important step towards reducing the environmental impact, and promoting circular economy practices, aligning with the goal “Responsible Consumption and Production” within United Nations’ Agenda 2030. The aim of the project was to develop bio-based prototype ski waxes and to evaluate and benchmark them with commercial petroleum-based PFAS-free ski waxes, in terms of hydrophobicity, glide performance and biodegradation.

Bio-based ski wax prototypes were blended using a mixture of ingredients approved for either topical application or ingestion by humans. Which ingredients and relative ratios to mix were based on melting points, general hydrophobic properties and generated knowledge from testing of earlier prototypes. It should be noted that only Vallakokerskan has the information about the exact content in the ski wax prototypes.

The hypothesis is that more hydrophobic, i.e. more water repellent, ski wax allows better transportation of the water film away from the ski/snow interface, providing lower friction and better glide. The hydrophobicity of ski waxes and ingredients was quantified from contact angle measurements using water and ethylene glycol as the liquid in a climate-controlled room (23°C and 50% relative humidity). To measure contact angles at sub-zero degrees, a less sensitive but portable device was put in a freezer room at -5°C where contact angles were measured using ethylene glycol.

The ski waxes showed similar hydrophobicity, in the measured static, advancing and receding contact angles, both in room temperature and at -5°C. However, the roll-off angle when the water droplet started to roll, was slightly lower for the commercial ski waxes than the bio-based prototypes. Greater differences in hydrophobicity and roll-off angles were observed for the ingredients compared to the ski wax.

In the glide tests on snow, it was difficult to separate the bio-based and commercial ski wax. This was both when considering the total glide time from four skiers testing each ski wax (ski pair) twice, and in the pairwise comparisons as is normally done when selecting skis before competition. These results show that the bio-based prototypes are comparable to commercial ski wax that is used both for competition and recreational skiing. While having similar glide function, the advantage of the bio-based ski wax is that it contains only naturally derived ingredients and that it seems to degrade slightly more rapidly in the environment. The biodegradation was compared between one bio-based and one petroleum-based ski wax using a respiration test where formed CO₂ was quantified over time. The estimated number of days required for complete degradation of the bio-based ski wax and commercial ski wax would be 223 days and 335 days, respectively, if the degradation continues at the same rate and if all carbon is converted to CO₂. In comparison to cellulose, both ski waxes degrade relatively slowly, most likely due to their hydrophobic properties.

During the project it was decided to also quantify and compare the hardness of the waxes since that is being discussed more and more as one additional characterisation technique in the project. The hardness measurements were done at -5°C. The maximum force encountered (firmness) when a probe was lowered into the sample during the compression test was taken as the hardness. Differences were obtained between the samples where the average firmness (hardness) was higher for the commercial green, blue and purple commercial ski waxes compared to the corresponding bio-based wax. However, the bio-based yellow was harder than the corresponding yellow commercial ski wax. Large differences in hardness at -5°C for the ingredients were noted.

The prototypes have been made with a mixture of different ingredients. The results from the hydrophobicity and hardness measurements of ingredients, can be used to select and modify the relative amount of each ingredient in the ski wax. If the hypothesis is that more hydrophobic and harder ingredients are better for the glide, it could be interesting to see if a wax containing a higher amount of those harder and more hydrophobic ingredients could increase the performance.

The focus in this project has been to develop a bio-based ski wax matrix. As a next step it would be interesting to develop and incorporate bio-based additives to try to increase the performance further. Another future outlook is to make the bio-based wax as a liquid product that are becoming more popular due the ease of application and less waste during the waxing procedure.

Solar energy will be a crucial part of the sustainable, fossil free energy production of the future. A majority of this will be produced by solar collectors and photovoltaics. Important for the efficient utilization of the incident solar energy for both technologies are a cover glass with antireflective coatings giving it a high solar transmittance. In the current paper we describe the development of antireflective mesoporous silica coatings on low-iron float glass using the aerosol-based nFOG™ deposition technique. The coatings exhibit a hexagonal and closed pore structure, high smoothness, superhydrophilic properties (contact angle <5°) and consistent thicknesses of approximately 110 nm. This is in line with optimal thickness determined from simulations of the antireflective behavior. Low-iron float glass coated on both sides show a highly reproducible solar weighted transmittance of 95% in the wavelength range 300–2500 nm and an antireflective effect increasing with incident angle. The smoothness, closed pores and low contact angle indicate a high cleanability, which in combination with the high transmittance render a competitive broadband antireflective coating well adapted for solar glass applications.

Solar energy will be a crucial part of the sustainable, fossil free energy production of the future. Amajority of this will be produced by solar collectors and photovoltaics. Important for the efficientutilization of the incident solar energy for both technologies are a cover glass with antireflectivecoatings giving it a high solar transmittance. In the current paper we describe the development ofantireflective mesoporous silica coatings on low-iron float glass using the aerosol-based nFOGTMdeposition technique. The coatings exhibit a hexagonal and closed pore structure, a high smoothness,and consistent thicknesses of approximately 110 nm. This is in line with optimal thicknessesdetermined from simulations of the antireflective behavior. Low-iron float glass coated on both sidesshow a highly reproducible solar weighted transmittance of 95 % in the wavelength range 300-2500nm and an antireflective effect increasing with incident angle. The smoothness and closed poresassociated with high cleanability, as well as high transmittance makes it a competitive broadbandantireflective coating well adapted for solar glass applications.

Superhydrophobic surfaces have high potential in self-cleaning and anti-fouling applications. We developed a one-step superhydrophobic coating formulation containing sodium oleate (NaOl), hydrophobized precipitated calcium carbonate and biobased cellulose nanofibrils (CNFs) hydrophobized with either alkyl ketene dimer (AKD) or amino propyl trimethoxy silane (APMS) as a binder to fix and distribute the particles. Coatings were made on paperboard and the wetting behavior of the surface was assessed. Static, advancing and receding contact angles with water as well as roll-off and water shedding angle were compared to coatings made with styrene butadiene latex as binder instead of CNFs. Modifications with alkyl ketene dimer showed most promising results for a viable process in achieving superhydrophobic paperboard but required reformulation of the coating with optimized and reduced amount of NaOl to avoid surfactant-induced wetting via excess NaOl. A static water contact angle of 150° was reached for the CNF-AKD. The use of CNFs enables the improvement of coating quality avoiding cracking with the use of nanocellulose as a renewable binder.

A pigment coating was developed to achieve superhydrophobicity in one step from a waterborne formulation containing aragonite calcium carbonate, hydrophobized using sodium oleate, latex binder and cross-linker. Coatings formulated ≤50 mass% and applied to polyethylene coated paperboard substrates displayed typical superhydrophobic features: water contact angles ≥150°, low roll-off angle and low stain sizes, but poor scratch and water resistance as well as foaming issues during preparation. Reformulation at higher solids content significantly improved scratch and water resistance properties. Water rinsing of the dried coatings further increased the water barrier capacity due to reduced surfactant-assisted wetting; findings were corroborated by detailed surface chemistry analyses showing the removal of surface-active components after water rinsing of the dried coatings. A plausible cause for the improved durability is the fact that capillary forces increase exponentially with increasing pigment volume fraction (power law exponent of 2.2) leading to efficient binder coverage during the early stage of pigment coating consolidation.

Researchers in natural fibers see opportunities in superhydrophobicity for fabrics or paper. The first challenge with natural fiber is their high hydrophilicity when the second is the perpetual search for water born coating  in papermaking. These challenges were overcome by a one pot formulation comprising a latex binder, precipitated calcium carbonate and  fatty acids to give their hydrophobicity to pigments 1.  In this study, we want to go further by replacing the petro-sourced latex with a new kind of fibers that are cellulose nanofibers (CNF).

Inspired by the Lotus leaf, superhydrophobic surfaces have been a center of interest in the last decade because of their high potential in industry for a variety of applications.  It is seen as the next generation of surface for anti-fouling and corrosive retardant in navy industry but also  in general  anti corrosive materials industry.  Now widely studied , mechanisms for manufacturing superhydrophobicity are well understood. Born from the alliance of low surface energy chemistry and physical structuration of surface, superhydrophobic materials give a water contact angle above 150° and a slidding angle below 10°.

Fundamental studies of superhydrophobicity have evolved toward several industrial applications. The present study concerns the formulation of pigmented foam aimed for water-borne superhydrophobic surface layers. An industrially viable process for a one-step water-borne superhydrophobic coating was developed in collaboration with industrial partners. A typical formulation contained calcium carbonate (preferably aragonite type), sodium oleate and carboxylic latex binder. The pigmented foam was laboratory rod coated onto paperboard substrates. During the drying the foamed structure collapses into a pigmented coating. The contact and rolling-off angles, droplet stain size and Cobb value were evaluated for different amounts of the added ingredients. The frictional resistance and water vapour permeability was measured for some of the samples.

More recent results show that through careful reformulation of the coating dispersions these pigmented foams can be prepared at considerably higher solids content, which is of utmost relevance to decrease drying time if implemented in an industrial process. It was also shown that the hydrostatic water resistance (Cobb value) and the mechanical robustness could be substantially improved compared to previous results. Surface spectroscopy data provided an explanation for the increased water resistance.

Organic phases trapped inside natural mineral samples are of considerable interest in astrobiology, geochemistry and geobiology. Examples of such organic phases are microfossils, kerogen and oil. Information about these phases is usually retrieved through bulk crushing of the rock which means both a risk of contamination and that the composition and spatial distribution of the organics to its host mineral is lost. An attractive of way to retrieve information about the organics in the rock is depth profiling using a focused ion beam. Recently, it was shown that it is possible to obtain detailed mass spectrometric information from oil-bearing fluid inclusions, i.e. small amounts of oil trapped inside a mineral matrix, using ToF-SIMS. Using a 10 keV C-60(+) sputter beam and a 25 keV Bi-3(+) analysis beam, oil-bearing inclusions in different minerals were opened and analysed individually. However, sputtering with a C-60(+) beam also induced other changes to the mineral surface, such as formation of topographic features and carbon deposition. In this paper, the cause of these changes is explored and the consequences of the sputter-induced features on the analysis of organic phases in natural mineral samples (quartz, calcite and fluorite) in general and fluid inclusions in particular are discussed. The dominating topographical features that were observed when a several micrometers deep crater is sputtered with 10 keV C-60(+) ions on a natural mineral surface are conical-shaped and ridge-like structures that may rise several micrometers, pointing in the direction of the incident C-60(+) ion beam, on an otherwise flat crater bottom. The sputter-induced structures were found to appear at places with different chemistry than the host mineral, including other minerals phases and fluid inclusions, while structural defects in the host material, such as polishing marks or scratches, did not necessarily result in sputter-induced structures. The ridge-like structures were often covered by a thick layer of deposited carbon. Despite the appearance of the sputter-induced structures and carbon deposition, most oil-bearing inclusions could successfully be opened and analysed. However, smaller inclusion (