Millions of tons of textile waste are landfilled or incinerated in the world every year due to insufficient recycle value streams and the complex composition of textile end products. The goal of this review is to highlight pathways for simplifying and separating textile wastes into valuable raw material streams that will promote their recovery and conversion to useful products. The discussion focuses on advances in sorting, separation, decolorization and conversion of polyester and cotton, the two most common textile fibers. Sorting processes are gaining automation using spectroscopic methods that detect chemical composition differences between materials to divide them into categories. Separation, through dissolving or degrading, makes it possible to deconstruct blended textiles and purify polymers, monomers and co-products. Waste cotton can produce high quality regenerated cellulose fibers, cellulose nanocrystals (CNCs) or biofuels. Waste polyester can produce colored yarns or can be chemically converted to its starting monomers for the recreation of virgin polymer as a complete closed loop. The current strategies for decolorization are presented. Life cycle assessment (LCA) studies found that recycling polyester/cotton blended fabrics for subsequent uses is more sustainable than incineration, and research on producing biomass-based poly-ester also offers feasible avenues for improving textile sustainability and promoting circular processing.
{"title":"Progress toward Circularity of Polyester and Cotton Textiles","authors":"Siyan Wang, S. Salmon","doi":"10.3390/suschem3030024","DOIUrl":"https://doi.org/10.3390/suschem3030024","url":null,"abstract":"Millions of tons of textile waste are landfilled or incinerated in the world every year due to insufficient recycle value streams and the complex composition of textile end products. The goal of this review is to highlight pathways for simplifying and separating textile wastes into valuable raw material streams that will promote their recovery and conversion to useful products. The discussion focuses on advances in sorting, separation, decolorization and conversion of polyester and cotton, the two most common textile fibers. Sorting processes are gaining automation using spectroscopic methods that detect chemical composition differences between materials to divide them into categories. Separation, through dissolving or degrading, makes it possible to deconstruct blended textiles and purify polymers, monomers and co-products. Waste cotton can produce high quality regenerated cellulose fibers, cellulose nanocrystals (CNCs) or biofuels. Waste polyester can produce colored yarns or can be chemically converted to its starting monomers for the recreation of virgin polymer as a complete closed loop. The current strategies for decolorization are presented. Life cycle assessment (LCA) studies found that recycling polyester/cotton blended fabrics for subsequent uses is more sustainable than incineration, and research on producing biomass-based poly-ester also offers feasible avenues for improving textile sustainability and promoting circular processing.","PeriodicalId":22103,"journal":{"name":"Sustainable Chemistry","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2022-09-05","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"74406563","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Joana C Bastos, N. S. Vieira, M. M. Gaspar, A. B. Pereiro, J. Araújo
Ionic liquids (ILs) are a potential solution to the general problem of low solubility, polymorphism and low bioavailability of active pharmaceutical ingredients (APIs). In this work, we report on the synthesis of three pharmaceutically active ILs (API-ILs) based on ibuprofen, one of the most commonly available over-the-counter nonsteroidal anti-inflammatory drugs (NSAIDs), with imidazolium cations ([C2C1Im][Ibu] and [C2(OH)C1Im][Ibu]) and a cholinium cation ([N1112(OH)][Ibu]). An upgrade to the aqueous solubility (water and biological simulated fluids) for the ibuprofen-based ILs relative to the ibuprofen’s neutral and salt form (sodium ibuprofen) was verified. The cytotoxic profiles of the synthesized API-ILs were characterized using two human cells lines, Caco-2 colon carcinoma cells and HepG-2 hepatocellular carcinoma cells, up to ibuprofen’s maximum plasma concentration (Cmax) without impairing their cytotoxicity response. Additionally, the EC50 in the Caco-2 cell line revealed similar results for both parent APIs and API-ILs. The biocompatibility of the ibuprofen-based ILs was also evaluated through a hemolytic activity assay, and the results showed that all the ILs were hemocompatible at concentrations higher than the ibuprofen Cmax. Moreover, the anti-inflammatory properties of the API-ILs were assessed through the inhibition of bovine serum albumin (BSA) denaturation and inhibition of cyclooxygenases (COX-1 and COX-2). The results showed that [C2C1Im][Ibu], [C2(OH)C1Im][Ibu] and [N1112(OH)][Ibu] maintained their anti-inflammatory response to ibuprofen, with improved selectivity towards COX-2, allowing the development of safer NSAIDs and the recognition of new avenues for selective COX-2 inhibitors in cancer chemotherapy and neurological diseases such as Alzheimer’s and Parkinson’s.
{"title":"Human Cytotoxicity, Hemolytic Activity, Anti-Inflammatory Activity and Aqueous Solubility of Ibuprofen-Based Ionic Liquids","authors":"Joana C Bastos, N. S. Vieira, M. M. Gaspar, A. B. Pereiro, J. Araújo","doi":"10.3390/suschem3030023","DOIUrl":"https://doi.org/10.3390/suschem3030023","url":null,"abstract":"Ionic liquids (ILs) are a potential solution to the general problem of low solubility, polymorphism and low bioavailability of active pharmaceutical ingredients (APIs). In this work, we report on the synthesis of three pharmaceutically active ILs (API-ILs) based on ibuprofen, one of the most commonly available over-the-counter nonsteroidal anti-inflammatory drugs (NSAIDs), with imidazolium cations ([C2C1Im][Ibu] and [C2(OH)C1Im][Ibu]) and a cholinium cation ([N1112(OH)][Ibu]). An upgrade to the aqueous solubility (water and biological simulated fluids) for the ibuprofen-based ILs relative to the ibuprofen’s neutral and salt form (sodium ibuprofen) was verified. The cytotoxic profiles of the synthesized API-ILs were characterized using two human cells lines, Caco-2 colon carcinoma cells and HepG-2 hepatocellular carcinoma cells, up to ibuprofen’s maximum plasma concentration (Cmax) without impairing their cytotoxicity response. Additionally, the EC50 in the Caco-2 cell line revealed similar results for both parent APIs and API-ILs. The biocompatibility of the ibuprofen-based ILs was also evaluated through a hemolytic activity assay, and the results showed that all the ILs were hemocompatible at concentrations higher than the ibuprofen Cmax. Moreover, the anti-inflammatory properties of the API-ILs were assessed through the inhibition of bovine serum albumin (BSA) denaturation and inhibition of cyclooxygenases (COX-1 and COX-2). The results showed that [C2C1Im][Ibu], [C2(OH)C1Im][Ibu] and [N1112(OH)][Ibu] maintained their anti-inflammatory response to ibuprofen, with improved selectivity towards COX-2, allowing the development of safer NSAIDs and the recognition of new avenues for selective COX-2 inhibitors in cancer chemotherapy and neurological diseases such as Alzheimer’s and Parkinson’s.","PeriodicalId":22103,"journal":{"name":"Sustainable Chemistry","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2022-08-13","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"80508084","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
J. Nisar, Salman Waris, Afzal Shah, F. Anwar, Ghulam Ali, Ali Ahmad, Faisal Muhammad
In this study, bio-oil was produced from the pyrolysis of de-oiled karanja seed press cake in the presence of abandoned anthill as the catalyst. The anthill was characterised by SEM, EDX, XRF, XRD and surface area and pore size analysis. The pyrolysis experiments were carried out in an indigenously made furnace in a nitrogen atmosphere from 310 to 400 °C. The pyrolysis oil was collected at an optimised temperature and analysed through gas chromatography–mass spectrometry (GC-MS). The compounds identified via GC-MS of non-catalytic bio-oil were in the range of C5 to C19, and compounds identified from catalytic bio-oil were in the range of C2–C63. Furthermore, thermogravimetric analysis of the karanja seed press cake without and with anthill was carried out in a nitrogen atmosphere with temperature programme rates of 3, 12, 20 and 30 °C·min−1. Kinetic parameters were determined by applying the Kissinger equation. The activation energy (Ea) values for hemicelluloses, cellulose and lignin were obtained as 99.7 ± 0.4, 182.9 ± 0.5 and 199.5 ± 0.7 kJ·mol−1 without catalyst; and with catalyst, the Ea were lowered to 74.8 ± 0.2, 83.1 ± 0.4 and 108.0 ± 0.5 kJ·mol−1, respectively. From the results, it was concluded that the catalyst played a key role in lowering the activation energy for the pyrolysis reaction and enhanced the quality of the bio-oil obtained as well.
{"title":"Production of Bio-Oil from De-Oiled Karanja (Pongamia pinnata L.) Seed Press Cake Via Pyrolysis: Kinetics and Evaluation of Anthill as the Catalyst","authors":"J. Nisar, Salman Waris, Afzal Shah, F. Anwar, Ghulam Ali, Ali Ahmad, Faisal Muhammad","doi":"10.3390/suschem3030022","DOIUrl":"https://doi.org/10.3390/suschem3030022","url":null,"abstract":"In this study, bio-oil was produced from the pyrolysis of de-oiled karanja seed press cake in the presence of abandoned anthill as the catalyst. The anthill was characterised by SEM, EDX, XRF, XRD and surface area and pore size analysis. The pyrolysis experiments were carried out in an indigenously made furnace in a nitrogen atmosphere from 310 to 400 °C. The pyrolysis oil was collected at an optimised temperature and analysed through gas chromatography–mass spectrometry (GC-MS). The compounds identified via GC-MS of non-catalytic bio-oil were in the range of C5 to C19, and compounds identified from catalytic bio-oil were in the range of C2–C63. Furthermore, thermogravimetric analysis of the karanja seed press cake without and with anthill was carried out in a nitrogen atmosphere with temperature programme rates of 3, 12, 20 and 30 °C·min−1. Kinetic parameters were determined by applying the Kissinger equation. The activation energy (Ea) values for hemicelluloses, cellulose and lignin were obtained as 99.7 ± 0.4, 182.9 ± 0.5 and 199.5 ± 0.7 kJ·mol−1 without catalyst; and with catalyst, the Ea were lowered to 74.8 ± 0.2, 83.1 ± 0.4 and 108.0 ± 0.5 kJ·mol−1, respectively. From the results, it was concluded that the catalyst played a key role in lowering the activation energy for the pyrolysis reaction and enhanced the quality of the bio-oil obtained as well.","PeriodicalId":22103,"journal":{"name":"Sustainable Chemistry","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2022-07-27","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"74181286","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Kadango Zombe, J. Nyirenda, Agape Lumai, Hellen Phiri
Cashew nutshell liquid (CNSL) is a cheap source of natural phenolic compounds that have numerous applications. These phenolic compounds have chemical structures with chromophores similar to those found in synthetic chemical UV-filters, which are present in commercial sunscreen products (SSPs). Thus, this study investigated the impact of solvents on the yield, total phenol content (TPC), total flavonoid content (TFC), and the sun protection factor (SPF) of crude CNSL. The percent yield ranged from (30.4 ± 0.7% to 49.3 ± 3.2%); hexane recorded the lowest yield, while ethanol recorded the highest. Acetone (101.2 ± 2.5 mg GA/g), methanol (99.5 ± 0.10), and chloroform (95.4 ± 3.7 mg GAE/g), recorded the highest TPC respectively, while hexane (33.3 ± 0.7 mg QE/g) recorded the highest TFC. The SPFs ranged from (22.1 ± 1.1 to 16.4 ± 0.8), chloroform (22.1 ± 1.1), acetone (21.5 ± 1.1), and methanol (19.3 ± 1.0) again recorded the highest values respectively, while hexane (16.4 ± 0.8) recorded the lowest. Our results revealed that extracting solvents has a significant impact on the yield and SPF of CNSL. Therefore, we propose that acetone, chloroform, and methanol, either alone or as mixtures, could be the best solvents for extracting CNSL with a good TPC and SPF.
{"title":"Impact of Solvent Type on Total Phenol and Flavonoid Content and Sun Protection Factor of Crude Cashew Nutshell Liquid","authors":"Kadango Zombe, J. Nyirenda, Agape Lumai, Hellen Phiri","doi":"10.3390/suschem3030021","DOIUrl":"https://doi.org/10.3390/suschem3030021","url":null,"abstract":"Cashew nutshell liquid (CNSL) is a cheap source of natural phenolic compounds that have numerous applications. These phenolic compounds have chemical structures with chromophores similar to those found in synthetic chemical UV-filters, which are present in commercial sunscreen products (SSPs). Thus, this study investigated the impact of solvents on the yield, total phenol content (TPC), total flavonoid content (TFC), and the sun protection factor (SPF) of crude CNSL. The percent yield ranged from (30.4 ± 0.7% to 49.3 ± 3.2%); hexane recorded the lowest yield, while ethanol recorded the highest. Acetone (101.2 ± 2.5 mg GA/g), methanol (99.5 ± 0.10), and chloroform (95.4 ± 3.7 mg GAE/g), recorded the highest TPC respectively, while hexane (33.3 ± 0.7 mg QE/g) recorded the highest TFC. The SPFs ranged from (22.1 ± 1.1 to 16.4 ± 0.8), chloroform (22.1 ± 1.1), acetone (21.5 ± 1.1), and methanol (19.3 ± 1.0) again recorded the highest values respectively, while hexane (16.4 ± 0.8) recorded the lowest. Our results revealed that extracting solvents has a significant impact on the yield and SPF of CNSL. Therefore, we propose that acetone, chloroform, and methanol, either alone or as mixtures, could be the best solvents for extracting CNSL with a good TPC and SPF.","PeriodicalId":22103,"journal":{"name":"Sustainable Chemistry","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2022-07-06","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"86516780","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Ilunga Monga, Vimla Paul, Sudhakar Muniyasamy, O. Zinyemba
This study was carried out to develop a green approach to synthesising sodium cyanide (NaCN) using hydrogen cyanide (HCN) extracted from cassava (Manihot esculenta Crantz) leaves after 120 min of maceration at 30 °C and 45 min of recovery under vacuum at 35–40 °C. The CN- ion released via autolysis was reacted with the Na+ ion following vacuum extraction of the former to produce NaCN by saturating the absorbing sodium hydroxide (NaOH) solution. This specific extraction method avoided direct contact between the cassava leaves homogenate and the absorbing solution. NaCN was crystallised by drying the NaCN slurry at 100 °C in an air oven. A total of 15.70 kg of fresh cassava leaves was needed to produce 32.356 g of NaCN (green-NaCN) (% NaCN yield = 0.21%). The results of X-ray diffraction, attenuated total reflectance–Fourier transform infrared spectroscopy and scanning electron microscopy with energy-dispersive X-ray spectroscopy, show that NaCN was successfully prepared using the proposed method. These spectral techniques showed that the control and green-NaCN contained sodium carbonate impurities. The latter was quantified by the titration experiments and was found to be 0.61% and 2.29% in the control and green-NaCN, respectively. Furthermore, the titration experiments revealed that the residual NaOH content was 1.63% in control NaCN and 4.68% in green-NaCN. The aim of modifying the green synthesis route for producing NaCN from cassava, developed by the Attahdaniel research group in 2013 and 2020, was achieved.
{"title":"Green Synthesis of Sodium Cyanide Using Hydrogen Cyanide Extracted under Vacuum from Cassava (Manihot esculenta Crantz) Leaves","authors":"Ilunga Monga, Vimla Paul, Sudhakar Muniyasamy, O. Zinyemba","doi":"10.3390/suschem3030020","DOIUrl":"https://doi.org/10.3390/suschem3030020","url":null,"abstract":"This study was carried out to develop a green approach to synthesising sodium cyanide (NaCN) using hydrogen cyanide (HCN) extracted from cassava (Manihot esculenta Crantz) leaves after 120 min of maceration at 30 °C and 45 min of recovery under vacuum at 35–40 °C. The CN- ion released via autolysis was reacted with the Na+ ion following vacuum extraction of the former to produce NaCN by saturating the absorbing sodium hydroxide (NaOH) solution. This specific extraction method avoided direct contact between the cassava leaves homogenate and the absorbing solution. NaCN was crystallised by drying the NaCN slurry at 100 °C in an air oven. A total of 15.70 kg of fresh cassava leaves was needed to produce 32.356 g of NaCN (green-NaCN) (% NaCN yield = 0.21%). The results of X-ray diffraction, attenuated total reflectance–Fourier transform infrared spectroscopy and scanning electron microscopy with energy-dispersive X-ray spectroscopy, show that NaCN was successfully prepared using the proposed method. These spectral techniques showed that the control and green-NaCN contained sodium carbonate impurities. The latter was quantified by the titration experiments and was found to be 0.61% and 2.29% in the control and green-NaCN, respectively. Furthermore, the titration experiments revealed that the residual NaOH content was 1.63% in control NaCN and 4.68% in green-NaCN. The aim of modifying the green synthesis route for producing NaCN from cassava, developed by the Attahdaniel research group in 2013 and 2020, was achieved.","PeriodicalId":22103,"journal":{"name":"Sustainable Chemistry","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2022-07-05","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"74897186","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
A. Bil, Bemba Abdellahi, G. Pourceau, A. Wadouachi
Sugar amides, such as aldonamides, are interesting, sugar-based molecules used in various fields, from detergency to medicine. Nevertheless, their valorization, especially as alternatives to petroleum-based substances, can be slowed down by their synthetic pathway, which is generally not in accordance with green chemistry principles, and is also not economically competitive. We propose herein a fast procedure for the synthesis of aldonamide-derived glycoconjugates with mechanochemistry. The conditions were first optimized with galactonolactone, used as a model lactone, and dodecylamine. After only 5 min of grinding of stoechiometric amounts of amine and lactone, in the presence of water used as a Liquid Assisted Grinding (LAG) agent, the corresponding galactonamide was isolated with a high yield (90%) after a simple aqueous work-up. The optimized conditions were then applied to a wide variety of amines and sugar lactones, showing the versatility of the methodology. Gluco- and ribono-lactone exhibited similarly excellent reactivity, showing that the procedure is not sugar-dependent. Furthermore, the procedure was shown to be compatible with various functional groups such as alkene, alkyne, thiol, ester and hydroxyl.
{"title":"Fast and Efficient Mechanosynthesis of Aldonamides by Aminolysis of Unprotected Sugar Lactones","authors":"A. Bil, Bemba Abdellahi, G. Pourceau, A. Wadouachi","doi":"10.3390/suschem3030019","DOIUrl":"https://doi.org/10.3390/suschem3030019","url":null,"abstract":"Sugar amides, such as aldonamides, are interesting, sugar-based molecules used in various fields, from detergency to medicine. Nevertheless, their valorization, especially as alternatives to petroleum-based substances, can be slowed down by their synthetic pathway, which is generally not in accordance with green chemistry principles, and is also not economically competitive. We propose herein a fast procedure for the synthesis of aldonamide-derived glycoconjugates with mechanochemistry. The conditions were first optimized with galactonolactone, used as a model lactone, and dodecylamine. After only 5 min of grinding of stoechiometric amounts of amine and lactone, in the presence of water used as a Liquid Assisted Grinding (LAG) agent, the corresponding galactonamide was isolated with a high yield (90%) after a simple aqueous work-up. The optimized conditions were then applied to a wide variety of amines and sugar lactones, showing the versatility of the methodology. Gluco- and ribono-lactone exhibited similarly excellent reactivity, showing that the procedure is not sugar-dependent. Furthermore, the procedure was shown to be compatible with various functional groups such as alkene, alkyne, thiol, ester and hydroxyl.","PeriodicalId":22103,"journal":{"name":"Sustainable Chemistry","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2022-06-22","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"78341272","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
M. Asad, Afzal Shah, F. Iftikhar, Rafia Nimal, J. Nisar, M. Zia
Water splitting has emerged as a sustainable, renewable and zero-carbon-based energy source. Water undergoes hydrogen evolution reaction (HER) and oxygen evolution reaction (OER) during electrolysis. However, among these half-cell reactions, OER is more energy demanding. Hence, the development of efficient catalysts for speeding up OER is a key for boosting up the commercial viability of electrolyzers. Typical binders like Nafion and PVDF are not preferred for designing commercial electrocatalysts as they can compromise conductivity. Thus, we have designed a novel and cost-effective binder-free tetra-metallic (Co-Cu-Zn-Fe) oxide catalyst that efficiently catalyzes OER. This catalyst was grown over the surface of Fluorine doped tin oxide (FTO) transducer by a facile potentiodynamic method. The structure and morphology of the modified electrode were characterized by X-ray diffraction (XRD), scanning electron microscopy, and energy dispersive X-ray spectroscopy. XRD analysis confirmed the deposition of CoFe2O4 and CuCo2O4 along with alloy formation of Co-Fe and Co-Cu. Similarly, EDX and SEM results show the presence of metals at the surface of FTO in accordance with the results of XRD. Linear scan voltammetry was employed for testing the performance of the catalyst towards accelerating OER in strongly alkaline medium of pH-13. The catalyst demonstrated stunning OER catalytic performance, with an overpotential of just 216 mV at 10 mA cm−2 current density. Moreover, the chronopotentiometric response revealed that the designed catalyst was stable at a potential of 1.80 V for 16 h. Thus, the designed catalyst is the first example of a highly stable, efficient, and inexpensive catalyst that catalyzes OER at the lowest overpotential.
水分解已经成为一种可持续、可再生和零碳的能源。水在电解过程中发生析氢反应(HER)和析氧反应(OER)。然而,在这些半电池反应中,OER需要更多的能量。因此,开发加速OER的高效催化剂是提高电解槽商业可行性的关键。典型的粘结剂如Nafion和PVDF不适合设计商用电催化剂,因为它们会降低导电性。因此,我们设计了一种新颖且具有成本效益的无粘结剂四金属(Co-Cu-Zn-Fe)氧化物催化剂,可有效催化OER。采用简便的电位动力学方法在氟掺杂氧化锡(FTO)换能器表面生长该催化剂。利用x射线衍射(XRD)、扫描电镜和能量色散x射线能谱对修饰电极的结构和形貌进行了表征。XRD分析证实了CoFe2O4和CuCo2O4的沉积以及Co-Fe和Co-Cu合金的形成。同样,EDX和SEM结果与XRD结果一致,表明FTO表面存在金属。采用线性扫描伏安法测试了催化剂在pH-13强碱性介质中加速OER的性能。该催化剂表现出惊人的OER催化性能,在10 mA cm−2电流密度下过电位仅为216 mV。此外,时间电位响应表明,所设计的催化剂在1.80 V的电位下稳定16小时。因此,所设计的催化剂是第一个在最低过电位下催化OER的高度稳定、高效和廉价的催化剂。
{"title":"Development of a Binder-Free Tetra-Metallic Oxide Electrocatalyst for Efficient Oxygen Evolution Reaction","authors":"M. Asad, Afzal Shah, F. Iftikhar, Rafia Nimal, J. Nisar, M. Zia","doi":"10.3390/suschem3030018","DOIUrl":"https://doi.org/10.3390/suschem3030018","url":null,"abstract":"Water splitting has emerged as a sustainable, renewable and zero-carbon-based energy source. Water undergoes hydrogen evolution reaction (HER) and oxygen evolution reaction (OER) during electrolysis. However, among these half-cell reactions, OER is more energy demanding. Hence, the development of efficient catalysts for speeding up OER is a key for boosting up the commercial viability of electrolyzers. Typical binders like Nafion and PVDF are not preferred for designing commercial electrocatalysts as they can compromise conductivity. Thus, we have designed a novel and cost-effective binder-free tetra-metallic (Co-Cu-Zn-Fe) oxide catalyst that efficiently catalyzes OER. This catalyst was grown over the surface of Fluorine doped tin oxide (FTO) transducer by a facile potentiodynamic method. The structure and morphology of the modified electrode were characterized by X-ray diffraction (XRD), scanning electron microscopy, and energy dispersive X-ray spectroscopy. XRD analysis confirmed the deposition of CoFe2O4 and CuCo2O4 along with alloy formation of Co-Fe and Co-Cu. Similarly, EDX and SEM results show the presence of metals at the surface of FTO in accordance with the results of XRD. Linear scan voltammetry was employed for testing the performance of the catalyst towards accelerating OER in strongly alkaline medium of pH-13. The catalyst demonstrated stunning OER catalytic performance, with an overpotential of just 216 mV at 10 mA cm−2 current density. Moreover, the chronopotentiometric response revealed that the designed catalyst was stable at a potential of 1.80 V for 16 h. Thus, the designed catalyst is the first example of a highly stable, efficient, and inexpensive catalyst that catalyzes OER at the lowest overpotential.","PeriodicalId":22103,"journal":{"name":"Sustainable Chemistry","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2022-06-21","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"88933586","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Synthetic polymers have a key role in modern society as they have allowed for great technological advancement since their discovery. However, the use of fossil-fuel-based raw materials and the pollution derived from plastics accumulation in the environment raised enormous concern, driving research efforts toward the identification of more sustainable alternatives. Bio-based functional molecules susceptible to ring-opening (co)polymerisation [RO(C)OP], such as lactones, cyclic carbonates, and oxiranes, represent an attractive source of monomers for the synthesis of more sustainable polymers. In this review, we describe the main advancement in this research field reported during the last seven years. In particular, we describe the preparation of monomers from (renewable) bio-sources such as sugars, terpenes, fatty acids, and carbon dioxide with a focus on structurally novel substrates. Both metal-mediated and organo-catalytic RO(CO)P methods are described, and the properties of derived functional polymers are discussed when relevant.
{"title":"Recent Advances in RO(CO)P of Bio-Based Monomers","authors":"Orlando Santoro, L. Izzo, Francesco Della Monica","doi":"10.3390/suschem3020017","DOIUrl":"https://doi.org/10.3390/suschem3020017","url":null,"abstract":"Synthetic polymers have a key role in modern society as they have allowed for great technological advancement since their discovery. However, the use of fossil-fuel-based raw materials and the pollution derived from plastics accumulation in the environment raised enormous concern, driving research efforts toward the identification of more sustainable alternatives. Bio-based functional molecules susceptible to ring-opening (co)polymerisation [RO(C)OP], such as lactones, cyclic carbonates, and oxiranes, represent an attractive source of monomers for the synthesis of more sustainable polymers. In this review, we describe the main advancement in this research field reported during the last seven years. In particular, we describe the preparation of monomers from (renewable) bio-sources such as sugars, terpenes, fatty acids, and carbon dioxide with a focus on structurally novel substrates. Both metal-mediated and organo-catalytic RO(CO)P methods are described, and the properties of derived functional polymers are discussed when relevant.","PeriodicalId":22103,"journal":{"name":"Sustainable Chemistry","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2022-05-31","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"85198827","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Prutha Joshi, Md Shakir Uddin Ahmed, K. Vig, M. Auad
Single-network hydrogels can have an internal porous structure and biocompatibility, but have lower mechanical properties. Combining these properties with another biocompatible and mechanically strong network can help in mimicking the extracellular matrix of native tissues to make them suitable for tissue scaffolds with desired performance. In the current objective, we combine the properties of poly (ethylene glycol) dimethacrylate (PEGDMA) macromer and polysaccharides as the two components in double networks (DN) for synergistic effects of both components resulting in the interpenetrating polymeric network for making it functional for replacement of injured tissues. The hydrogels were characterized by physical properties like swelling ratio, mechanical properties like tensile and compressive modulus, and rheological behavior. The chemical composition was studied using Fourier transform infrared spectroscopy (FTIR), and the thermal behavior using differential scanning calorimetry (DSC) experiments. Biodegradability and mechanical strength both are gained using double networks (DN), thus making it resemble more like living tissues. DN hydrogels were tested for cell compatibility for possible application in tissue engineering. Furthermore, these properties may allow their application as tissue-engineered scaffolds.
{"title":"Formulation of the Polymeric Double Networks (DNs) for Biomedical Applications with Physicochemical Properties to Resemble a Biological Tissue","authors":"Prutha Joshi, Md Shakir Uddin Ahmed, K. Vig, M. Auad","doi":"10.3390/suschem3020016","DOIUrl":"https://doi.org/10.3390/suschem3020016","url":null,"abstract":"Single-network hydrogels can have an internal porous structure and biocompatibility, but have lower mechanical properties. Combining these properties with another biocompatible and mechanically strong network can help in mimicking the extracellular matrix of native tissues to make them suitable for tissue scaffolds with desired performance. In the current objective, we combine the properties of poly (ethylene glycol) dimethacrylate (PEGDMA) macromer and polysaccharides as the two components in double networks (DN) for synergistic effects of both components resulting in the interpenetrating polymeric network for making it functional for replacement of injured tissues. The hydrogels were characterized by physical properties like swelling ratio, mechanical properties like tensile and compressive modulus, and rheological behavior. The chemical composition was studied using Fourier transform infrared spectroscopy (FTIR), and the thermal behavior using differential scanning calorimetry (DSC) experiments. Biodegradability and mechanical strength both are gained using double networks (DN), thus making it resemble more like living tissues. DN hydrogels were tested for cell compatibility for possible application in tissue engineering. Furthermore, these properties may allow their application as tissue-engineered scaffolds.","PeriodicalId":22103,"journal":{"name":"Sustainable Chemistry","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2022-05-30","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"83306209","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
This study investigated and compared the acid-free electropolishing of copper with the state-of-the-art acidic electropolishing process. The acid-free medium used in this study is based on a deep eutectic solvent comprised of 2:1 ethylene glycol and choline chloride. The electrochemical study included voltammetry and chronoamperometry tests during the electropolishing process. The characterization techniques used were atomic force microscopy (AFM) and digital microscopy, and surface morphology comparisons summarized the electropolishing efficiency of phosphoric acid and acid-free deep eutectic solvent treatments for high-purity copper. Electropolishing copper with a deep eutectic solvent resulted in a mirror finish and a post-treatment surface that was 8× smoother than the original metal surface prior to electropolishing treatments with a smoothing efficiency of 91.1 ± 1.5%. This eco-friendly solution produced polished surfaces superior to those surfaces treated with industry standard acid electrochemistry treatments of 1 M H3PO4.
本研究对铜的无酸电解抛光工艺和目前最先进的酸性电解抛光工艺进行了研究和比较。本研究中使用的无酸介质是基于由2:1乙二醇和氯化胆碱组成的深度共晶溶剂。电化学研究包括电解抛光过程中的伏安法和计时安培法测试。采用原子力显微镜(AFM)和数字显微镜进行表征,并通过表面形貌比较总结了磷酸和无酸深共晶溶剂处理对高纯铜的电抛光效率。用深度共晶溶剂对铜进行电抛光后,表面光洁度达到镜面光洁度的8倍,抛光效率为91.1±1.5%。这种环保溶液产生的抛光表面优于工业标准的1 M H3PO4酸电化学处理的表面。
{"title":"Comparison of Electrochemical Polishing Treatments between Phosphoric Acid and a Deep Eutectic Solvent for High-Purity Copper","authors":"T. Abdel-Fattah, J. Loftis","doi":"10.3390/suschem3020015","DOIUrl":"https://doi.org/10.3390/suschem3020015","url":null,"abstract":"This study investigated and compared the acid-free electropolishing of copper with the state-of-the-art acidic electropolishing process. The acid-free medium used in this study is based on a deep eutectic solvent comprised of 2:1 ethylene glycol and choline chloride. The electrochemical study included voltammetry and chronoamperometry tests during the electropolishing process. The characterization techniques used were atomic force microscopy (AFM) and digital microscopy, and surface morphology comparisons summarized the electropolishing efficiency of phosphoric acid and acid-free deep eutectic solvent treatments for high-purity copper. Electropolishing copper with a deep eutectic solvent resulted in a mirror finish and a post-treatment surface that was 8× smoother than the original metal surface prior to electropolishing treatments with a smoothing efficiency of 91.1 ± 1.5%. This eco-friendly solution produced polished surfaces superior to those surfaces treated with industry standard acid electrochemistry treatments of 1 M H3PO4.","PeriodicalId":22103,"journal":{"name":"Sustainable Chemistry","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2022-05-19","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"89431374","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}