Article
Polymer Science
Tushar Kanti Maiti, Jitendra Singh, Subrata Kumar Maiti, Jagannath Majhi, Arihant Ahuja, Manjinder Singh, Anasuya Bandyopadhyay, Gaurav Manik, Sujay Chattopadhyay
Summary: In this study, the introduction of sulfonic acid functionalized graphene oxide (SGO) into Perfluorosulfonic acid (PFSA) membranes improved the glass transition temperature (Tg), mechanical properties, proton conductivity, and single-cell performance. The loading of SGO increased the Tg and modulus of PFSA composite membranes, leading to enhanced proton conductivity and fuel cell performance.
EUROPEAN POLYMER JOURNAL
(2022)
Article
Engineering, Environmental
Y. Prykhodko, K. Fatyeyeva, L. Hespel, S. Marais
Summary: Over 50% of energy is currently produced by burning non-renewable fossil fuels, leading to the release of greenhouse gases and environmental pollution. As a result, research on renewable energy sources, storage, and energy transformation devices has become increasingly important in recent years. Fuel cells, particularly proton exchange membrane fuel cells, are considered a promising energy device with ongoing developments in membrane technology.
CHEMICAL ENGINEERING JOURNAL
(2021)
Article
Polymer Science
Ekaterina Yu. Safronova, Daria Yu. Voropaeva, Anna A. Lysova, Oleg V. Korchagin, Vera A. Bogdanovskaya, Andrey B. Yaroslavtsev
Summary: By changing the preparation and pretreatment conditions, the properties of Nafion membranes can be optimized. In this study, a Nafion-NMP membrane with higher conductivity and comparable hydrogen permeability was obtained by casting from a Nafion dispersion in N-methyl-2-pyrrolidone. The increase in conductivity is attributed to the optimization of the Nafion-NMP microstructure, which improves the connectivity of the pores and channels system. This leads to an increased capacity of the membrane electrode assembly compared to a commercial Nafion (R) 212 membrane.
Article
Chemistry, Physical
Fatima C. Teixeira, Ana de Sa, Antonio P. S. Teixeira, V. M. Ortiz-Martinez, A. Ortiz, I Ortiz, C. M. Rangel
Summary: The study focused on the development of new Nafion membranes by incorporating aryl- or azaheteroaromatic bisphosphonate compounds as dopants, resulting in enhanced proton conductivity properties compared to commercial Nafion membranes. These doped membranes showed improved performance in fuel cells at different temperatures, with a maximum power output of around 383 mW cm(-2) at 70 degrees C. The membranes also demonstrated potential advantages in restricting gas crossover, as indicated by higher open circuit potentials compared to Nafion membranes under the same conditions.
INTERNATIONAL JOURNAL OF HYDROGEN ENERGY
(2021)
Article
Environmental Sciences
Asif Jamil, Sikander Rafiq, Tanveer Iqbal, Hafiza Aroosa Aslam Khan, Haris Mahmood Khan, Babar Azeem, M. Z. Mustafa, Abdulkader S. Hanbazazah
Summary: Fuel cells are environmentally friendly technology with high efficiency and economic advantages. Proton exchange membranes, especially for hydrogen fuel cells, have great potential but face challenges in terms of cost and degradation of proton exchange capacity over time.
Article
Biochemistry & Molecular Biology
Takeru Wakiya, Manabu Tanaka, Hiroyoshi Kawakami
Summary: Novel nanofiber framework (NfF)-based composite membranes composed of phytic acid (Phy)-doped polybenzimidazole nanofibers (PBINf) and Nafion matrix electrolyte were fabricated through the compression process, showing higher proton conductivity and lower activation energy at low relative humidity.
Article
Energy & Fuels
Osung Kwon, Kwangjin Oh, JaeHyoung Park, Sam Park, Tae Gwan Lee, Byungrak Son
Summary: This study investigated the proton conductivity enhancement mechanism of Nafion-silica sulfuric acid (SSA) composite membranes using atomic force microscopy. It was found that among different weight percentages of SSA, 1 wt% SSA exhibited the highest proton conductivity and thermal properties, attributed to the separation of the hydrophilic ionic channel network and hydrophobic backbone in the microstructural morphology.
INTERNATIONAL JOURNAL OF ENERGY RESEARCH
(2021)
Article
Chemistry, Physical
Lei Liu, Chao Wang, Zhenfeng He, Duo Pan, Binbin Dong, Sravanthi Vupputuri, Zhanhu Guo
Summary: Nafion/APNB membranes were prepared by introducing APNB architecture, increasing hydrophobic domains, and forming ordered water channels to improve ion conductivity; Nafion/APNB-2.5% membrane has the highest swelling ratio, while Nafion/APNB-5% membrane has the highest power density.
JOURNAL OF POWER SOURCES
(2021)
Article
Chemistry, Physical
Subir Paul, Sang-June Choi, Hee Jin Kim
Summary: The incorporation of high-proton-conductive Co-tri MOF improved the proton conductivity of Aquivion (R), resulting in an enhanced cell performance and a 66% increase in proton conductivity compared to the pristine membrane. The effect of Co-tri MOF on the structural morphology and thermal properties of the Aquivion (R) membrane was also investigated.
Article
Materials Science, Multidisciplinary
Mohammad Bagher Karimi, Fereidoon Mohammadi, Khadijeh Hooshyari, Shokoufeh Jalilzadeh
Summary: The aim of this study is to reduce the tortuosity of proton conductive pathways within polymer electrolyte membranes for anhydrous PEM fuel cells. By incorporating microsize chopped fibers, modified nanosilica, and a deep eutectic solvent into the Nafion matrix, the proton conductive pathways are extended and the conductivity is greatly improved. The measurements show that the Nafion/DES composite membrane with 5 wt% short fibers and 2 wt% nanosilica exhibits super proton conductivity and promising fuel cell performance.
MACROMOLECULAR MATERIALS AND ENGINEERING
(2022)
Review
Chemistry, Physical
Shahbaz Ahmad, Tahir Nawaz, Asghar Ali, Mehmet Fatih Orhan, Ayesha Samreen, Arunachala M. Kannan
Summary: Proton exchange membrane fuel cells are considered efficient and clean energy conversion devices, but their high manufacturing cost remains a major barrier to their general acceptance and commercialization. Lowering the cost of the electrolyte and catalyst is the main strategy for reducing fuel cell cost. The development of low-cost and high-performance electrolyte membranes is a top priority.
INTERNATIONAL JOURNAL OF HYDROGEN ENERGY
(2022)
Article
Chemistry, Physical
Bapun Barik, Yejin Yun, Aniket Kumar, Hohan Bae, Yeon Namgung, Jun-Young Park, Sun-Ju Song
Summary: Acidic group functionalized graphene oxide (GO) is used to improve the quality of state-of-the-art Nafion electrolytes for next-generation fuel cell application. Single-step-phosphorylated graphene oxide (sPGO) modified Nafion (sPGO/NF) achieves high proton conductivity, chemical durability, and power density under actual fuel cell conditions.
INTERNATIONAL JOURNAL OF HYDROGEN ENERGY
(2023)
Article
Polymer Science
Rudzani Sigwadi, Touhami Mokrani, Phumlani Fortune Msomi
Summary: Electrospun PAN nanofibers decorated with ZrO2 and blended with graphene oxide nanofibers were used to improve the performance and conductivity of Nafion membrane in fuel cells. The modified composite membrane demonstrated higher proton conductivity and overall membrane properties, as well as superior fuel cell efficiency compared to commercial Nafion and existing literature. With lower methanol permeability and a proton conductivity of 5.46 x 10(-8) cm(2)/s and 0.46 mS/cm respectively, the Nafion-PAN/ZrO2-GO nanofiber membrane achieved a fuel cell performance of 75.9 mWcm(-2) at a current density of 250 mAcm(-2). The composite membrane shows potential for application in fuel cells.
JOURNAL OF POLYMER RESEARCH
(2022)
Article
Chemistry, Physical
Hyunseung Lee, Hongdae Seo, Seong Ku Kim, Insung Bae
Summary: The aligned nanostructure of perfluorinated polymer electrolytes, achieved through capillary force lithography, enables increased proton conductivity. A hierarchical structure is realized through soft lithography, allowing control over the structures of proton-transporting channels. The line-patterned membranes show enhanced proton conductivities, as confirmed by electrochemical impedance analysis. Moreover, an increased interfacial contact area improves the power generation efficiency of the membrane-electrode assembly in proton-exchange membrane fuel cells.
ACS APPLIED ENERGY MATERIALS
(2022)
Review
Chemistry, Physical
Sahng Hyuck Woo, So Young Lee, Young-Gi Yoon, Arnaud Rigacci, Jung-Je Woo, Christian Beauger, Hyoung-Juhn Kim
Summary: The incorporation of nanoclays into polymer matrixes improves the performance of proton exchange membranes (PEMs) in proton exchange membrane fuel cells (PEMFCs), especially at high temperatures and low relative humidity (RH). Nanoclays also enhance the mechanical properties and reduce the cost of composite membranes.
JOURNAL OF POWER SOURCES
(2022)
Article
Polymer Science
Rudzani Sigwadi, Touhami Mokrani, Phumlani Fortune Msomi
Summary: Electrospun PAN nanofibers decorated with ZrO2 and blended with graphene oxide nanofibers were used to improve the performance and conductivity of Nafion membrane in fuel cells. The modified composite membrane demonstrated higher proton conductivity and overall membrane properties, as well as superior fuel cell efficiency compared to commercial Nafion and existing literature. With lower methanol permeability and a proton conductivity of 5.46 x 10(-8) cm(2)/s and 0.46 mS/cm respectively, the Nafion-PAN/ZrO2-GO nanofiber membrane achieved a fuel cell performance of 75.9 mWcm(-2) at a current density of 250 mAcm(-2). The composite membrane shows potential for application in fuel cells.
JOURNAL OF POLYMER RESEARCH
(2022)
Article
Polymer Science
Rudzani Sigwadi, Touhami Mokrani, Phumlani Msomi, Fulufhelo Nemavhola
Summary: This study investigates the impact of acidic nanoparticles on fuel cell performance. The results show that the Nafion(R) membrane modified with sulfated zirconium and zirconium phosphate nanoparticles exhibits higher proton conductivity and better mechanical strength, making it suitable for fuel cell applications.
Article
Engineering, Biomedical
L. Lebea, H. M. Ngwangwa, D. A. Desai, F. Nemavhola
Summary: Corrosion in the human body can cause structural changes in materials and release harmful substances, which may lead to complications. This study evaluated the effects of different solutions and immersion times on 3D-printed titanium alloy samples and found that corrosion in solutions can result in weight loss and instability of dental implants.
APPLIED BIONICS AND BIOMECHANICS
(2022)
Article
Engineering, Biomedical
Zwelihle Ndlovu, Dawood Desai, Thanyani Pandelani, Harry Ngwangwa, Fulufhelo Nemavhola
Summary: This study evaluates the fitting capabilities of four constitutive hyperelastic material models to experimental data of porcine sclera soft tissue. It estimates the material parameters and discusses their applicability to a finite element model, considering the statistical dispersion. The results show that all four material models have good correlations above 96%, with the polynomial (anisotropic) model having the best correlation of 98%. However, the estimated material parameters vary widely, requiring normalization of test data to avoid lengthy optimization processes. For application to finite element models, normalizing the test data can reduce the search region for optimization algorithms. The anisotropy of sclera tissue is more influenced by fiber-related properties than background material matrix-related properties.
APPLIED BIONICS AND BIOMECHANICS
(2022)
Article
Engineering, Chemical
Harry Ngwangwa, Fulufhelo Nemavhola, Thanyani Pandelani, Makhosasana Msibi, Israel Mabuda, Neil Davies, Thomas Franz
Summary: This study evaluates the passive mechanical property differences in the three main walls of the rat heart based on biaxial tensile test data. The findings suggest that there are variations in the mechanical properties of different ventricle walls, including differences in the toe region strain range, strain energy storage, and anisotropy. These findings emphasize the importance of considering wall-specific material parameters to accurately model ventricular mechanics.
Article
Multidisciplinary Sciences
Harry Ngwangwa, Thanyani Pandelani, Makhosasana Msibi, Israel Mabuda, Letlhogonolo Semakane, Fulufhelo Nemavhola
Summary: This study investigated the biomechanical properties of the esophagus under biaxial mechanical tensile testing, fitting experimental data to six hyperelastic constitutive models and finding that the Four-Fiber model had the best fit.
Article
Energy & Fuels
Gayi Nyongombe, G. L. Kabongo, I. T. Bello, L. L. Noto, M. S. Dhlamini
Summary: This study investigated the effect of drying temperature on the crystallite size and lattice strain of NiCoAl-LDH and its impact on the electrochemical properties. The results showed that drying temperature significantly influenced the crystalline structure and electrochemical properties of NiCoAl-LDH. The best electrochemical performance was observed at a drying temperature of 80 degrees C.
Article
Green & Sustainable Science & Technology
Moshito Lethabo Mothupi, Phumlani Fortune Msomi
Summary: In this study, a general method was used to improve the overall performance of alkaline anion exchange membranes by blending polyethersulfone quaternized with imidazolium groups with imidazolium functionalized graphene oxide inorganic filler (ImGO). The 0.5% ImGO content showed better ionic transport, swelling ratio, water uptake, alkaline stability, ion exchange capacity, and exhibited a peak power of 130 mW·cm(-2).
Review
Chemistry, Physical
Nkosingiphile E. Zikalala, Shohreh Azizi, Sithembela A. Zikalala, Ilunga Kamika, Malik Maaza, Ali Akbar Zinatizadeh, Touhami Mokrani, Kasinathan Kaviyarasu
Summary: Global water scarcity and contamination are addressed through the use of nanotechnology, specifically zinc oxide nanoparticles (ZnO NPs) synthesized through green chemistry. This article reviews and discusses the biogenic synthesis and characterization techniques of ZnO NPs using various biological sources, such as plants, bacteria, fungi, algae, and derivatives. The applications of these ZnO NPs in water treatment, including their mechanisms of action and adsorbent properties, are outlined. Challenges facing the green synthesis of nanomaterials are also highlighted.
Article
Polymer Science
Tlhologelo Lekoane, Phumlani F. Msomi
Summary: In this study, a series of quaternized polysulfone (QPSF) membranes blended with ZSM-5 zeolite anion exchange membranes (AEMs) were fabricated by solution casting for use as separators in Al-air batteries. The QPSF/3 wt% ZSM-5 composite membrane showed the best performance with high ion exchange capacity and ion conductivity. It also exhibited stable discharge voltage and specific capacity in a laboratory fabricated Al-air cell. This study provides a promising anion exchange composite membrane separator candidate for Al-air battery applications.
JOURNAL OF APPLIED POLYMER SCIENCE
(2023)
Article
Polymer Science
Cornelia M. Phela, Rudzani Sigwadi, Phumlani F. Msomi
Summary: A series of proton exchange membranes (PEMs) with different sulfonated graphene oxide (SGO) were prepared and evaluated for possible application in an iron-air/flow battery. The addition of SGO improved the water uptake and reduced the swelling ratio of the membranes. The 0.75% SGO exhibited the highest proton conductivity and better dispersion, elemental distribution, and morphology, indicating its potential as a stable and efficient filler in a composite proton exchange membrane.
POLYMERS FOR ADVANCED TECHNOLOGIES
(2023)
Article
Biochemistry & Molecular Biology
Livhuwani Modau, Rudzani Sigwadi, Touhami Mokrani, Fulufhelo Nemavhola
Summary: The purpose of this study was to identify the steps involved in fabricating silica/chitosan composite membranes and their suitability for fuel cell applications. The composite membranes were successfully modified with silica, showing exceptional results in terms of proton conductivity and methanol permeability.
Article
Chemistry, Applied
Ismaila Taiwo Bello, David Omoefe Idisi, Kamaldeen Olasunkanmi Suleman, Yetunde Ajayeoba, Oluwaseun Adedokun, Ayodeji Oladiran Awodugba, Mokhotjwa Simon Dhlamini
Summary: This study presents the simulations of a hybrid Cu2ZnSnS4-based solar cell with a planar heterojunction structure using a One-Dimensional Solar cell capacitance simulator (SCAPS-1D). The results show that hybridization of different absorber layers is achievable and the efficiency of as-CZTS structures is higher than that of PSCS structures.
BIOINTERFACE RESEARCH IN APPLIED CHEMISTRY
(2022)
