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Efficiency enhancement of hydrogen based electric powertrain is becoming highly relevant for medium to heavy duty transportation due to advantages of eminent electrochemical cell design and advances in infrastructure accessibility. Herein, a facile and highly effective fabrication process has been reported for the first time to demonstrate an outstanding mechanical strength and electrical conductivity simultaneously in the carbon rich composite designed to enhance the fuel cell performance. Improvement of composites with different advanced reinforced materials such as carbon veil, recycled carbon fiber as well as functional additives such as carbon black, multiwalled nanotube, etc. Was investigated through a holistic approach of optimized parameters. Advanced composite plates have been designed to be mechanically flexible, electrically conductive and cost effective; this newly designed composite for bipolar plate supersedes by far the US Department of Energy (DOE) target for fuel cell bipolar plate with a flexural strength of over 64Â MPa and exceeding electrical conductivity of 200Â S/cm. Notably, tuned process parameters as well as novel architecture of materials such as continuous carbon fiber and carbon veil can facilitate the fabrication of a light-weight high-performance carbon polymer composite for a wide range of applications including battery electrodes, supercapacitors, fuel cells and solar cell., Validerad;2023;Nivå 2;2023-08-15 (joosat);Licens fulltext: CC BY License

Efficiency enhancement of hydrogen based electric powertrain is becoming highly relevant for medium to heavy duty transportation due to advantages of eminent electrochemical cell design and advances in infrastructure accessibility. Herein, a facile and highly effective fabrication process has been reported for the first time to demonstrate an outstanding mechanical strength and electrical conductivity simultaneously in the carbon rich composite designed to enhance the fuel cell performance. Improvement of composites with different advanced reinforced materials such as carbon veil, recycled carbon fiber as well as functional additives such as carbon black, multiwalled nanotube, etc. Was investigated through a holistic approach of optimized parameters. Advanced composite plates have been designed to be mechanically flexible, electrically conductive and cost effective; this newly designed composite for bipolar plate supersedes by far the US Department of Energy (DOE) target for fuel cell bipolar plate with a flexural strength of over 64Â MPa and exceeding electrical conductivity of 200Â S/cm. Notably, tuned process parameters as well as novel architecture of materials such as continuous carbon fiber and carbon veil can facilitate the fabrication of a light-weight high-performance carbon polymer composite for a wide range of applications including battery electrodes, supercapacitors, fuel cells and solar cell., Validerad;2023;Nivå 2;2023-08-15 (joosat);Licens fulltext: CC BY License

Technical lignins, kraft, soda, lignoboost, and hydrolysis lignins were used for the production of carbon particles at different carbonization temperatures, 1000 °C and 1400 °C. The results showed that the lignin source and carbonization temperature significantly influenced the carbon quality and microstructure of the carbon particles. Soda lignin carbonized up to 1400 °C showed higher degree of graphitization and exhibited the highest electrical conductivity of 335 S·m−1, which makes it suitable for applications, such as electromagnetic interference shielding and conductive composite based structural energy storage devices. The obtained carbon particles also showed high surface area and hierarchical pore structure. Kraft lignin carbonized up to 1400 °C gives the highest BET surface area of 646 m2 g−1, which makes it a good candidate for electrode materials in energy storage applications. The energy storage application has been validated in a three-electrode set up device, and a specific capacitance of 97.2 F g−1 was obtained at a current density of 0.1 A g−1 while an energy density of 1.1 Wh kg−1 was observed at a power density of 50 W kg−1. These unique characteristics demonstrated the potential of kraft lignin-based carbon particles for electrochemical energy storage applications., Validerad;2022;Nivå 2;2022-10-25 (hanlid)

Technical lignins, kraft, soda, lignoboost, and hydrolysis lignins were used for the production of carbon particles at different carbonization temperatures, 1000 °C and 1400 °C. The results showed that the lignin source and carbonization temperature significantly influenced the carbon quality and microstructure of the carbon particles. Soda lignin carbonized up to 1400 °C showed higher degree of graphitization and exhibited the highest electrical conductivity of 335 S·m−1, which makes it suitable for applications, such as electromagnetic interference shielding and conductive composite based structural energy storage devices. The obtained carbon particles also showed high surface area and hierarchical pore structure. Kraft lignin carbonized up to 1400 °C gives the highest BET surface area of 646 m2 g−1, which makes it a good candidate for electrode materials in energy storage applications. The energy storage application has been validated in a three-electrode set up device, and a specific capacitance of 97.2 F g−1 was obtained at a current density of 0.1 A g−1 while an energy density of 1.1 Wh kg−1 was observed at a power density of 50 W kg−1. These unique characteristics demonstrated the potential of kraft lignin-based carbon particles for electrochemical energy storage applications., Validerad;2022;Nivå 2;2022-10-25 (hanlid)

Carbon aerogels prepared from low-cost renewable resources are promising electrode materials for future energy storage applications. However, their electrochemical properties must be significantly improved to match the commercially used high-carbon petroleum products. This paper presents a facile method for the green synthesis of carbon aerogels (CAs) from lignocellulosic materials and graphene dots (GDs) from commercially available biochar. The produced carbon aerogels exhibited a hierarchical porous structure, which facilitates energy storage by forming an electrical double-layer capacitance. Surprisingly, the electrochemical analyses of the GD-doped carbon aerogels revealed that in comparison to pristine carbon aerogels, the surface doping of GDs enhanced the electrochemical performance of carbon aerogels, which can be attributed to the combined effect from both double-layer capacitance and pseudocapacitance. Herein, we designed and demonstrated the efficacy of a supercapacitor device using our green carbon electrode as a sustainable option. These green carbon aerogels have opened a window for their practical use in designing sustainable energy storage devices., Validerad;2021;Nivå 2;2021-11-30 (johcin)

Carbon aerogels prepared from low-cost renewable resources are promising electrode materials for future energy storage applications. However, their electrochemical properties must be significantly improved to match the commercially used high-carbon petroleum products. This paper presents a facile method for the green synthesis of carbon aerogels (CAs) from lignocellulosic materials and graphene dots (GDs) from commercially available biochar. The produced carbon aerogels exhibited a hierarchical porous structure, which facilitates energy storage by forming an electrical double-layer capacitance. Surprisingly, the electrochemical analyses of the GD-doped carbon aerogels revealed that in comparison to pristine carbon aerogels, the surface doping of GDs enhanced the electrochemical performance of carbon aerogels, which can be attributed to the combined effect from both double-layer capacitance and pseudocapacitance. Herein, we designed and demonstrated the efficacy of a supercapacitor device using our green carbon electrode as a sustainable option. These green carbon aerogels have opened a window for their practical use in designing sustainable energy storage devices., Validerad;2021;Nivå 2;2021-11-30 (johcin)

Date palm fiber (Phoenix dactylifera L.) is a natural biopolymer rich in lignocellulosic components. Its high cellulose content lends them to the extraction of tiny particles like microcrystalline cellulose (MCC) and nanocrystalline cellulose (NCC). These cellulose-derived small size particles can be used as an alternative biomaterial in wide fields of application due to their renewability and sustainability. In the present work, NCC (A) and NCC (B) were isolated from date palm MCC at 60 min and 90 min hydrolysis times, respectively. The isolated NCC product was subjected to characterization to study their properties differences. With the hydrolysis treatment, the yields of produced NCC could be attained at between 22% and 25%. The infrared-ray functional analysis also revealed the isolated NCC possessed a highly exposed cellulose compartment with minimized lignoresidues of lignin and hemicellulose. From morphology evaluation, the nanoparticles’ size was decreased gradually from NCC (A) (7.51 nm width, 139.91 nm length) to NCC (B) (4.34 nm width, 111.51 nm length) as a result of fragmentation into cellulose fibrils. The crystallinity index was found increasing from NCC (A) to NCC (B). With 90 min hydrolysis time, NCC (B) showed the highest crystallinity index of 71% due to its great cellulose rigidity. For thermal analysis, NCC (B) also exhibited stable heat resistance, in associating with its highly crystalline cellulose structure. In conclusion, the NCC isolated from date palm MCC would be a promising biomaterial for various applications such as biomedical and food packaging applications.

Date palm fiber (Phoenix dactylifera L.) is a natural biopolymer rich in lignocellulosic components. Its high cellulose content lends them to the extraction of tiny particles like microcrystalline cellulose (MCC) and nanocrystalline cellulose (NCC). These cellulose-derived small size particles can be used as an alternative biomaterial in wide fields of application due to their renewability and sustainability. In the present work, NCC (A) and NCC (B) were isolated from date palm MCC at 60 min and 90 min hydrolysis times, respectively. The isolated NCC product was subjected to characterization to study their properties differences. With the hydrolysis treatment, the yields of produced NCC could be attained at between 22% and 25%. The infrared-ray functional analysis also revealed the isolated NCC possessed a highly exposed cellulose compartment with minimized lignoresidues of lignin and hemicellulose. From morphology evaluation, the nanoparticles’ size was decreased gradually from NCC (A) (7.51 nm width, 139.91 nm length) to NCC (B) (4.34 nm width, 111.51 nm length) as a result of fragmentation into cellulose fibrils. The crystallinity index was found increasing from NCC (A) to NCC (B). With 90 min hydrolysis time, NCC (B) showed the highest crystallinity index of 71% due to its great cellulose rigidity. For thermal analysis, NCC (B) also exhibited stable heat resistance, in associating with its highly crystalline cellulose structure. In conclusion, the NCC isolated from date palm MCC would be a promising biomaterial for various applications such as biomedical and food packaging applications.

Food contamination leading to the spoilage and growth of undesirable bacteria, which can occur at any stage along the food chain, is a significant problem in the food industry. In the present work, biopolymer polybutylene succinate (PBS) and polybutylene succinate/tapioca starch (PBS/TPS) films incorporating Biomaster-silver (BM) and SANAFOR® (SAN) were prepared and tested as food packaging to improve the lifespan of fresh chicken breast fillets when kept in a chiller for seven days. The incorporation of BM and SAN into both films demonstrated antimicrobial activity and could prolong the storability of chicken breast fillets until day 7. However, PBS + SAN 2%, PBS/TPS + SAN 1%, and PBS/TPS + SAN 2% films showed the lowest microbial log growth. In quality assessment, incorporation of BM and SAN into both film types enhanced the quality of the chicken breast fillets. However, PBS + SAN 1% film showed the most notable enhancement of chicken breast fillet quality, as it minimized color variation, slowed pH increment, decreased weight loss, and decelerated the hardening process of the chicken breast fillets. Therefore, we suggest that the PBS + SAN and PBS/TPS + SAN films produced in this work have potential use as antimicrobial packaging in the future.

Food contamination leading to the spoilage and growth of undesirable bacteria, which can occur at any stage along the food chain, is a significant problem in the food industry. In the present work, biopolymer polybutylene succinate (PBS) and polybutylene succinate/tapioca starch (PBS/TPS) films incorporating Biomaster-silver (BM) and SANAFOR® (SAN) were prepared and tested as food packaging to improve the lifespan of fresh chicken breast fillets when kept in a chiller for seven days. The incorporation of BM and SAN into both films demonstrated antimicrobial activity and could prolong the storability of chicken breast fillets until day 7. However, PBS + SAN 2%, PBS/TPS + SAN 1%, and PBS/TPS + SAN 2% films showed the lowest microbial log growth. In quality assessment, incorporation of BM and SAN into both film types enhanced the quality of the chicken breast fillets. However, PBS + SAN 1% film showed the most notable enhancement of chicken breast fillet quality, as it minimized color variation, slowed pH increment, decreased weight loss, and decelerated the hardening process of the chicken breast fillets. Therefore, we suggest that the PBS + SAN and PBS/TPS + SAN films produced in this work have potential use as antimicrobial packaging in the future.

The mycelial growth ability of 13 white rot fungi were separately evaluated in kraft, organosolv, and soda black liquor agar-plates. The fungus able to best grow and decolorize black liquor agar-plates was grown in organosolv black liquor to investigate whether it reduced organosolv lignin molar mass. The fungus Bjerkandera adusta showed fair mycelial growth and decolorization ability in 10% black liquor-agar plates. To obtain low-molecular weight (MW) lignin, B. adusta was cultivated in 150-mL Erlenmeyer flasks containing 10% black liquor and maintained in a shaking culture for 15 days. Lignin was recovered from each Erlenmeyer flask by acid precipitation and was analysed by size exclusion chromatography (SEC) and Fourier transform infrared (FTIR) spectroscopy. The lowest MW of lignin from black liquor was observed on the 11th and 12th days, at 1461 and 1790 kDa, respectively, with the polydispersity close to 1.0, indicating that the molecules were similar in size. Fourier transform infrared spectra bands showed modification of the lignin structure during 9 days, with new bands appearing after five days of lignin biodegradation.

The mycelial growth ability of 13 white rot fungi were separately evaluated in kraft, organosolv, and soda black liquor agar-plates. The fungus able to best grow and decolorize black liquor agar-plates was grown in organosolv black liquor to investigate whether it reduced organosolv lignin molar mass. The fungus Bjerkandera adusta showed fair mycelial growth and decolorization ability in 10% black liquor-agar plates. To obtain low-molecular weight (MW) lignin, B. adusta was cultivated in 150-mL Erlenmeyer flasks containing 10% black liquor and maintained in a shaking culture for 15 days. Lignin was recovered from each Erlenmeyer flask by acid precipitation and was analysed by size exclusion chromatography (SEC) and Fourier transform infrared (FTIR) spectroscopy. The lowest MW of lignin from black liquor was observed on the 11th and 12th days, at 1461 and 1790 kDa, respectively, with the polydispersity close to 1.0, indicating that the molecules were similar in size. Fourier transform infrared spectra bands showed modification of the lignin structure during 9 days, with new bands appearing after five days of lignin biodegradation.