| 1. |
- Chen, Jun, et al.
(författare)
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Graphene-enhanced, wear-resistant and thermal-conductive, anti-/de-icing Gelcoat composite coating
- 2024
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Ingår i: Advanced Composites and Hybrid Materials. - 2522-0128 .- 2522-0136. ; 7:1
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Tidskriftsartikel (refereegranskat)abstract
- Wind power is considered as a sustainable and environmentally friendly energy source. However, the occurrence of icing poses significant challenges to energy production, particularly in frigid regions during the winter season. Conventional strategies employed for preventing and removing ice formation have proven inadequate due to their inability to satisfy intricate requirements or their high energy consumption. In this study, a commercial gelcoat coating was adopted as an anti-/de-icing coating by introducing different concentrations of graphene and boron nitride into the gelcoat coating through physical mixing. Extensive investigations were conducted on the correlation between anti-/de-icing, wear resistance, and thermal conductivity. Notably, the incorporation of nanoparticles induced a rise in the surface roughness, resulting in prolonged resistance to water icing on the coated surface. The wear resistance and thermal conductivity of the composite coating were enhanced through the inclusion of boron nitride and graphene. The building of thermal conductive particle networks improved thermal conductivity which can lead to improved heat transfer and heat distribution. At the same time, the enhanced gelcoat composite coating exhibited exceptional passive anti-/de-icing performance and wear resistance. This coating can replace commercial coatings to improve anti-/de-icing efficiency for the existing active heating anti-/de-icing techniques available in the market.In this study, we aimed to enhance the wear resistance, thermal conductivity, and anti-/de-icing properties of a gelcoat composite coating by incorporating graphene and boron nitride. The gelcoat graphene coating showed better performance than the gelcoat boron nitride coating and pure gelcoat coating. The improved wear resistance of the gelcoat graphene coating can be attributed to the two-dimensional layer structure of graphene, while the addition of graphene resulted in a threefold increase in the thermal conductivity of the gelcoat composite coating compared to the pure gelcoat coating. The gelcoat composite coatings exhibited a high-water contact angle and low ice adhesive force. It was observed that as the surface roughness increased, the water contact angle also increased. The increase in ice adhesion after abrasion proves that abrasion is always detrimental to de-icing. Despite the extension of icing delay time, the large number of grooves and bumps created by wear results in stronger mechanical interlocking. It is worth mentioning that gelcoat graphene coating still demonstrated lower ice adhesive strength than gelcoat boron nitride coating and pure gelcoat coating. Overall, we successfully developed a gelcoat graphene coating with improved thermal conductivity, wear resistance, and low ice adhesive properties. This novel composite coating has the potential to significantly enhance the efficiency of existing heating technologies for anti-/de-icing applications, thereby reducing energy consumption associated with the turbine blades’ anti-/de-icing system.
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| 2. |
- Stróżyk, Michał A., et al.
(författare)
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Decreasing the environmental impact of carbon fibre production via microwave carbonisation enabled by self-assembled nanostructured coatings
- 2024
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Ingår i: Advanced Composites and Hybrid Materials. - 2522-0128 .- 2522-0136. ; 7:2
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Tidskriftsartikel (refereegranskat)abstract
- The use of carbon fibre (CF)-based composites is of growing global importance due to their application in high-end sectors such as aerospace, automotive, construction, sports and leisure amongst others. However, their current high production cost, high carbon footprint and reduced production capability limit their use to high-performance and luxury applications. Approximately 50% of the total cost of CF production is due to the thermal conversion of polyacrylonitrile (PAN) precursor fibre (PF) to CF as it involves the use of high energy consumption and low heating efficiency in large furnaces. Looking at this scenario, this study proposes in the present study to use microwave (MW) heating to convert PF to CF. This is scientifically and technologically challenging since PF does not absorb microwave energy. While MW plasma has been utilised to carbonise fibres, it is the high temperature from the plasma that does the carbonisation and not the MW absorption of the fibres. Therefore, for the first time, this research shows how carbonisation temperatures of >1000 °C can be reached in a matter of seconds through the use of a novel microwave (MW) susceptor nanocoating methodology developed via a layer-by-layer assembly of multiwall carbon nanotubes (MWCNTs) on the PF surface. Remarkably, these CFs can be produced in an inexpensive domestic microwave and exhibit mechanical performance equivalent to CF produced using conventional heating. Additionally, this study provides a life cycle and environmental impact analysis which shows that MW heating reduces the energy demand and environmental impact of lignin-based CF production by up to 66.8% and 69.5%, respectively. Graphical Abstract: (Figure presented.)
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| 3. |
- Sun, Pengliang, et al.
(författare)
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Artificial chloroplast-like phosphotungstic acid — iron oxide microbox heterojunctions penetrated by carbon nanotubes for solar photocatalytic degradation of tetracycline antibiotics in wastewater
- 2022
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Ingår i: Advanced Composites and Hybrid Materials. - : Springer Science+Business Media B.V.. - 2522-0128 .- 2522-0136. ; 5:4, s. 3158-3175
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Tidskriftsartikel (refereegranskat)abstract
- Doping-inducted heterojunction is an effective strategy to boost the semiconductor photocatalysis. In this work, an artificial chloroplast-like HPWx@Fe2O3-CNTs photocatalyst was developed by a continuous hydrothermal process and microwave irradiation. This catalyst showed an excellent performance in degradation of biotoxic tetracycline (under mild conditions, tetracycline can be degraded by 100% in 100 min), the apparent rate constant of degradation was 5.5 times higher than that of pure Fe2O3. This is attributed to the synergistic photocatalysis of the Keggin unit of phosphotungstic acid to Fe2O3, which makes the photogenerated electrons trapped in the W5d vacancy state of the Keggin unit, thus delaying the recombination of electron–hole pairs. Moreover, the low-cost HPWx@Fe2O3-CNTs photocatalyst displayed a strong magnetism, leading to a facile separation of the photocatalyst. A relatively stable efficiency of degradation can be maintained. In the light radiation of “Baoxiang river” (Yunnan, China) water sample, the total organic carbon content decreased to 10.58%, which revealed a strong ability of organic carbon mineralization. In addition, E. coli as bacteria indicator was selected to quantitatively monitor the comprehensive toxicity changes in wastewater upon this photocatalytic technology. Both experimental and theoretical investigations demonstrated that the unique nano-scale biomimetic structures with high active sites, improvement of visible-light response, and separation and transfer of electrons and holes in heterojunction were responsible for the superior catalytic results.
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| 4. |
- Liu, Wei, et al.
(författare)
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Microencapsulated phase change material through cellulose nanofibrils stabilized Pickering emulsion templating
- 2023
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Ingår i: advanced composites and hybrid materials. - 2522-0128. ; 6:4
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Tidskriftsartikel (refereegranskat)abstract
- Phase change materials (PCMs) possess remarkable capability to store and release substantial amounts of energy during the processes of melting and crystallization across a wide temperature range, thus holding great promise in applications related to temperature regulation and thermal energy storage. Herein, to effectively address PCM leakage and enhance thermal conduction, PCM microcapsules with melamine-formaldehyde resin (MF) shell were prepared using in situ polymerization of Pickering emulsions stabilized by cellulose nanofibrils (CNFs). CNFs were selected as the stabilizers for the Pickering emulsions and as reinforcing nanofillers for the MF shell, owing to their excellent emulsifying capability, high mechanical strength, and sustainable nature. Paraffin wax (PW) was utilized as the PCM material. The resulting PCM microcapsules with MF resin shells and PW core had a diameter ranging from 2 to 4 & mu;m. Results showed that microcapsule with the core-shell ratio of 2 (Micro-2.0) exhibited the highest latent heat of crystallization and latent heat of fusion, measuring approximately 128.40 J/g and 120.23 J/g, respectively. The encapsulation efficiency of Micro-2.0 was determined to be approximately 79.84%.
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