Article
Chemistry, Physical
Wail Al Zoubi, Rosy Amalia Kurnia Putri, Young Gun Ko
Summary: In this study, a magnesium-based inorganic layer was prepared using low temperature-interfacial plasma electrolysis to optimize chemical stability and understand the role of coordination complexes in plasma-assisted electrochemical reactions. Optimal complexes with a metal-capped core formed by melamine (MEL) terminated with amino groups have less porous surfaces and contain metal oxide nanoparticles and stable magnesium-aluminate.
JOURNAL OF MOLECULAR LIQUIDS
(2021)
Article
Chemistry, Applied
Wail Al Zoubi, Mohammad Ehtisham Khan, Young Gun Ko
Summary: In this study, a flower-like hierarchy with outstanding chemical stability and electrochemical performance was achieved through the self-assembly of 8-hydroxyquinoline and 1.10-phenanthroline on a plasma electrolysis-treated porous material surface.
PROGRESS IN ORGANIC COATINGS
(2022)
Article
Chemistry, Multidisciplinary
Van Dien Dang, Raghunath Putikam, Ming-Chang Lin, Kung-Hwa Wei
Summary: In this study, a 3D transition metal dichalcogenide (TMD)-MoS2 nanoflower grown on a 2D tungsten oxide-anchored graphene nanosheet (MoS2@W-G) was found to be a superior catalyst for the hydrogen evolution reaction (HER) in both acidic and alkaline conditions. The optimized weight ratio of MoS2@W-G achieved low overpotential, small Tafel slope, and high exchange current density in acidic media. The same composite also exhibited stable HER performance using real seawater in both acidic and alkaline media. These findings suggest a new approach for developing 3D/2D TMD/graphene electrocatalysts for HER applications using seawater.
Article
Chemistry, Physical
Yangyang Ding, Xiaoqiang Du, Xiaoshuang Zhang
Summary: The study introduces a multifunctional electrocatalyst for water electrolysis with excellent performance, especially in catalyzing urea oxidation as a potential alternative to slow oxygen evolution. By analyzing the structure-function relationship of the material, it was found that Cu-Ni3S2@NiFe LDH-200 excels in oxygen evolution and urea oxidation reactions.
APPLIED SURFACE SCIENCE
(2022)
Article
Engineering, Environmental
Kyong-Hwan Chung, Young-Kwon Park, Sun-Jae Kim, Sang-Chai Kim, Sang-Chul Jung
Summary: This study attempted to develop a hybrid reaction system that combines photochemical decomposition, liquid-phase plasma, photocatalyst, and electrolysis for efficient decomposition and hydrogen production from high-concentration ethanolamine-resistant wastewater. The consecutive reaction process successfully decomposed ethanolamine wastewater and achieved complete removal of chemical oxygen demand (COD) and total nitrogen. The hydrogen production rates were significantly increased in the hybrid reaction system compared to a single electrolysis reaction, indicating the potential for enhanced hydrogen production through the combination of photocatalysis and electrolysis.
CHEMICAL ENGINEERING JOURNAL
(2022)
Article
Chemistry, Inorganic & Nuclear
Xue Chen, Hongfei Yin, Xiaoyong Yang, Weining Zhang, Dongdong Xiao, Zhen Lu, Yongzheng Zhang, Ping Zhang
Summary: Compared with the Haber Bosch process, the electrochemical nitrogen reduction reaction (NRR) offers a more environmentally friendly and sustainable route for ammonia synthesis. This study developed Co-doped Fe3S4 nanoflowers as a catalyst for NRR, achieving high Faradaic efficiency and NH3 yield rate. The introduction of Co atoms promoted N-2 absorption and accelerated the catalytic process, providing a pathway for enhancing ammonia synthesis using morphology and doping engineering for Fe-based electrocatalysts.
INORGANIC CHEMISTRY
(2022)
Article
Engineering, Multidisciplinary
Mosab Kaseem, Young Gun Ko
Summary: The present study successfully fabricated stable smart coatings on AZ31 Mg alloy by decorating layered double hydroxide film with protein molecules functionalized by n-type semi-conductor nanoparticles. This coating was found to significantly enhance the anticorrosion properties by increasing barrier to diffusion, preventing charge transport, and utilizing the large surface area of the LDH film for dopant liberation.
COMPOSITES PART B-ENGINEERING
(2021)
Review
Biotechnology & Applied Microbiology
Pravin D. Patil, Radhika K. Kelkar, Neha P. Patil, Pradnya V. Pise, Sadhana P. Patil, Arundhatti S. Patil, Nishant S. Kulkarni, Manishkumar S. Tiwari, Ajay N. Phirke, Shamraja S. Nadar
Summary: The use of organic-inorganic hybrid nanoflowers as support material for enzyme immobilization has become popular due to their stability, ease of preparation, and enhanced catalytic activity. However, their low density and high dispersion make them difficult to handle and separate. Magnetic nanoflowers have emerged as a promising alternative platform for enzyme immobilization due to their easy separation, structural stability, and ability to enhance catalytic efficiency. This review focuses on different methods for designing magnetic nanoflowers, examples of enzymes immobilized in magnetic nanoflowers, their applications, and ways to improve material properties for enhanced catalytic activity, structural stability, and scalability.
CRITICAL REVIEWS IN BIOTECHNOLOGY
(2023)
Article
Chemistry, Organic
Fengyi Li, Yating Liang, Xuan Zhan, Sheng Zhang, Man-Bo Li
Summary: An electrochemical redox-neutral C(sp(3))-H amidation was developed using N-alkoxyamide as an amidating reagent. N-alkoxyamides exhibited higher reactivity compared to direct reactions with primary amides. This novel approach allowed for the synthesis of a wide range of bioactive amides and direct derivatization of pharmaceuticals under oxidant- and transition metal-free conditions. Solar energy could be directly utilized in this electrochemical transformation, providing a clean and practical method for amide synthesis.
ORGANIC CHEMISTRY FRONTIERS
(2022)
Article
Mechanics
Kaikai Li, Yingxi Xie, Min Yu, Jiao Gao, Biao Tang, Longsheng Lu
Summary: The evolution of plasma droplets on the surface of electrosurgical scalpels under different heating temperatures was studied. The results showed that electrolysis dominated the evolution at lower heating temperatures, while coagulation suppressed electrolysis at higher heating temperatures. The laser-patterned surface exhibited excellent anti-adhesive properties compared to the original surface.
Article
Chemistry, Physical
Hongxu Cheng, Hong Luo, Xuefei Wang, Zhimin Pan, Qiancheng Zhao, Chaofang Dong, Xiaogang Li
Summary: This study investigates the cathode plasma electrolytic deposition (CPED) for titanium and obtains TiN and TiN/CrN coatings. The TiN/CrN coating shows better diffusion resistance and lower polarization resistance compared to the TiN coating, thus having a promising application prospect.
INTERNATIONAL JOURNAL OF HYDROGEN ENERGY
(2023)
Review
Biotechnology & Applied Microbiology
Zichen Wang, Ruirui Wang, Zixin Geng, Xiuyan Luo, Jiahui Jia, Saizhao Pang, Xianwei Fan, Muhammad Bilal, Jiandong Cui
Summary: Hybrid nanomaterials have emerged as a new interface of nanobiocatalysis, with inorganic crystal nanoflowers and metal-organic frameworks (MOFs) being of particular interest for enzyme immobilization. However, there is a lack of literature reviews on enzyme@MOF and enzyme-hybrid nanoflower composites and their synthesis strategies and applications in biotechnology. This review discusses innovative synthetic strategies and biotechnological applications of enzyme@MOF and enzyme-hybrid nanoflower composites, aiming to provide insights and ideas for future research.
CRITICAL REVIEWS IN BIOTECHNOLOGY
(2023)
Article
Materials Science, Biomaterials
Mosab Kaseem, Han-Choel Choe
Summary: This study investigates the enhancement of the protective and bioactive properties of Ti-6Al-4V alloy by incorporating cellulose microcrystalline (CMC) additive to form titania-based inorganic layers. A novel acetatephosphate-based electrolyte with CMC was formulated to modify the porous structure of the oxide layers made via plasma electrolysis. The presence of CMC changed the characteristics of plasma discharges, leading to different pore sizes and surface roughness of the oxide layers. The coated samples in CMC-containing electrolytes exhibited improved protective and bioactive properties, making them potential implants for dental applications.
ACS BIOMATERIALS SCIENCE & ENGINEERING
(2023)
Review
Chemistry, Multidisciplinary
Thinh Viet Dang, Moon Il Kim
Summary: Organic-inorganic hybrid nanoflowers (HNFs) have attracted widespread research interest for their ability to efficiently entrap organic components, resulting in high activity, stability, and recyclability. Recent efforts have focused on developing advanced HNFs composed of diversified components to achieve different functionalities, particularly in biosensing and biomedical applications. This review presents an overview of recent advances in diversified component incorporated HNFs, discussing synthetic strategies, structural characteristics, unique properties, and potential biotechnological applications. The challenges and future opportunities of HNFs are also discussed.
KOREAN JOURNAL OF CHEMICAL ENGINEERING
(2023)
Article
Multidisciplinary Sciences
Wan Ru Leow, Simon Voelker, Raoul Meys, Jianan Erick Huang, Shaffiq A. Jaffer, Andre Bardow, Edward H. Sargent
Summary: The production of hydrogen and hydrocarbon refining contribute significantly to CO2 emissions in the chemicals industry. Coupled electrification can cut emissions by up to 39%, even with the current electricity mix. Chemicals manufacturing is a major greenhouse gas emitter, with over half of the emissions coming from ammonia and oxygenates. By using electrolyzer systems that convert hydrocarbons to oxygenates and generate H-2 from water, emissions from fossil-based ammonia and oxygenates can be reduced by up to 88%. Low-carbon electricity is not necessary for a substantial reduction in global chemical industry emissions, as a 39% reduction can be achieved with the electricity carbon footprint available in the US or China today. Researchers interested in this area are provided with considerations and recommendations.
NATURE COMMUNICATIONS
(2023)
Article
Metallurgy & Metallurgical Engineering
S. Fatimah, M. P. Kamil, D. Han, W. Al-Zoubi, Y. G. Ko
Summary: Plasma electrolytic oxidation (PEO) is a promising surface treatment for generating anti-corrosive coatings on lightweight metals. This study demonstrates that using sub-zero electrolyte can improve the coating compactness and corrosion resistance.
JOURNAL OF MAGNESIUM AND ALLOYS
(2022)
Article
Nanoscience & Nanotechnology
Wail Al Zoubi, Abdul Wahab Allaf, Bassem Assfour, Young Gun Ko
Summary: This study reports a one-step bottom-up approach for preparing small and highly stable Cu nano-particles supported on a porous inorganic coating. The unique embedded structure of this catalyst allows for high catalytic activity and stability in the hydrogenation reaction of 4-nitrophenol and the reduction of other compounds. Density functional theory calculations were used to confirm the experimental observations, showing that CuNPs have a favorable adsorption energy and activity compared to Fe and AgNPs. This approach can also be applied to the preparation of other single-atom catalysts with excellent performance.
ACS APPLIED MATERIALS & INTERFACES
(2022)
Article
Chemistry, Physical
Siti Fatimah, Nisa Nashrah, Kadir Tekin, Young Gun Ko
Summary: This study developed a protective and functional oxide layer on pure titanium through one-step plasma electrolytic oxidation (PEO) in a short time, using highly concentrated aluminate solution. The analysis showed the successful formation of Al2TiO5 compound through Al2O3 incorporation, along with the spontaneous development of TiO2 with plasma swarms. The electrochemical performance demonstrated the protective and functional capabilities of the oxide layer, which resulted from the respective amounts of Al2O3 and Al2TiO5. These capabilities were achieved in a short processing time, leading to reduced production costs.
Article
Materials Science, Multidisciplinary
Abdelkarim Chaouiki, Maryam Chafiq, Young Gun Ko, Aisha H. Al-Moubaraki, Fatima Zahra Thari, Rachid Salghi, Khalid Karrouchi, Khalid Bougrin, Ismat H. Ali, Hassane Lgaz
Summary: In this study, two thiazolidinediones were found to enhance the corrosion resistance of carbon steel in hydrochloric acid solution. Experimental and computational methods were used to investigate the interactions between the inhibitors and iron, as well as their effects on corrosion reactions. Morphological analysis also revealed the changes in the surface of carbon steel due to the addition of the inhibitors.
Article
Materials Science, Multidisciplinary
M. P. Kamil, D. Sandyaning, A. S. Wismogroho, K. Corneliasari, B. Hermanto, T. Sudiro, A. Afandi
Summary: This study investigated a Ni-38Mo binary alloy, focusing on Ni solid solution and Ni-Mo intermetallic phases. A homogeneous Ni-Mo alloy powder obtained by mechanical alloying was consolidated using spark plasma sintering (SPS). The main phases observed after sintering were a Ni(Mo) solid solution and the delta-NiMo intermetallic phase.
Article
Chemistry, Physical
Aisha H. Al-Moubaraki, Abdelkarim Chaouiki, Jamilah M. Alahmari, Wesam A. Al-hammadi, Ehteram A. Noor, Azza A. Al-Ghamdi, Young Gun Ko
Summary: This study demonstrates the superior corrosion inhibition properties of three plant-based products on mild steel in phosphoric acid. Experimental and computational approaches were used to evaluate the anti-corrosion and adsorption characteristics of these products. The results showed that the products form protective layers with high electrochemical stability and effectively protect the metal against aggressive acidic solutions. The experimental and theoretical results are in good agreement, suggesting the possibility of using natural organic products as substitutes for conventional compounds in the fabrication of materials with effective anti-corrosion performance.
Article
Biochemistry & Molecular Biology
Hassane Lgaz, Han-seung Lee, Savas Kaya, Rachid Salghi, Sobhy M. Ibrahim, Maryam Chafiq, Lahcen Bazzi, Young Gun Ko
Summary: The development of corrosion inhibitors with outstanding performance requires continuous efforts from researchers, engineers, and practitioners. This study investigates the electronic features, adsorption characteristics, and bonding mechanisms of two pyridine oximes, 2-pyridylaldoxime (2POH) and 3-pyridylaldoxime (3POH), with an iron surface. The simulations reveal that 3POH exhibits covalent bonding with iron in both its neutral and protonated states, while 2POH only forms bonds in its protonated form. The excellent adsorption properties and corrosion inhibition performance of 3POH can be attributed to its low stability compared to 2POH molecules.
Article
Chemistry, Physical
I. Putu Widiantara, Rosy Amalia Kurnia Putri, Da In Han, Warda Bahanan, Eun Hye Lee, Chang Hoon Woo, Jee-Hyun Kang, Jungho Ryu, Young Gun Ko
Summary: Metal injection molding (MIM) is a fast and accurate method for producing elaborate and complex items. This study focused on the characterization of the green part of steel produced using MIM. Parameters such as dual gates position, injection temperature, and injection pressure were analyzed. Results showed that the green part had a good filling confidence, minimal defects, and decent homogeneity, providing valuable guidelines for high-quality MIM of steel.
Article
Chemistry, Physical
Sang Heon Cho, Young Jin Lee, Warda Bahanan, Jeong Moo Oh, Dong-Ju Kim, Jee-Hyun Kang, Jungho Ryu, I. Putu Widiantara, Young Gun Ko
Summary: This investigation explored the effect of reduction sequence on texture and anisotropy during rolling of ferritic stainless steel. The study utilized two different reduction sequences, 67% + 50% (route A) and 50% + 67% (route B), with a total height reduction of 83%. Microstructural analysis showed no significant difference in grain morphology between route A and route B. However, route B developed a sharper texture on all components along the gamma-fiber and had a higher fraction of boundaries with 38 degrees < 111 > misorientations. This led to optimal deep drawing properties and improved resistance against ridging due to the formation of a microstructure with a homogeneous distribution of <111>//ND orientation.
Article
Materials Science, Multidisciplinary
Ehteram A. Noor, Aisha H. Al-Moubaraki, Dalal I. Al-Masoudi, Maryam Chafiq, Abdelkarim Chaouiki, Young Gun Ko
Summary: The corrosion behavior of carbon steel X36 in soil solutions from different areas of Jeddah City was studied. The corrosion rates decreased with increasing immersion period, and the corrocity followed the order Sh > Ja > Ob-Sh > Sa > Sf. The results from electrochemical and weight loss measurements were consistent.
Article
Chemistry, Physical
Warda Bahanan, Siti Fatimah, Hyunseok Song, Eun Hye Lee, Dong-Ju Kim, Hae Woong Yang, Chang Hoon Woo, Jungho Ryu, I. Putu Widiantara, Young Gun Ko
Summary: Metal injection molding (MIM) is a near-net-shape manufacturing process used in automobile and device industries to fabricate complex geometric components. This study investigated the green part of pure copper processed with MIM at an injection temperature of approximately 180 degrees C and injection pressure of approximately 5 MPa. A computational analysis based on the Moldflow program was used to evaluate the fill confidence, quality prediction, and pressure drop of three distinct regions in the green part. The results showed localized behavior in the ring and edge regions, which was affected by processing parameters such as the gate position. Microstructural observation and microhardness analysis confirmed the presence of pores and slight non-uniformity in one specific part due to localized pore agglomeration. The simulation results agreed well with the experimental data, providing useful guidelines for MIM-treated pure copper with complex shapes.
Article
Chemistry, Physical
Siti Fatimah, Farah Hazmatulhaq, Yujun Sheng, Tri Suhartono, Jeong Moo Oh, Nisa Nashrah, Jee-Hyun Kang, Young Gun Ko
Summary: This study investigates the use of ultrasonic vibration during plasma electrolytic oxidation (PEO) to enhance the corrosion resistance of magnesium alloys. It is found that the presence of ultrasonic waves facilitates the formation of a uniform and dense oxide layer on the alloys through plasma softening, acoustic streaming, and improved mass transport. The compactness of the oxide layer increases its protective properties against corrosive environments. However, increasing the ultrasonic frequency from 40 to 135 kHz suppresses the optimal growth of the oxide layer due to the presence of super-soft plasma swarms, resulting in a lower coating thickness. The integration of ultrasonic vibration with PEO shows promise for practical implementation in industries aiming to enhance corrosion protection, manipulate microstructures, and composition of magnesium alloys.
Article
Chemistry, Multidisciplinary
Oday I. Mousa, Salah S. Al-Luaibi, Alaa S. Al-Mubarak, Hassane Lgaz, Belkheir Hammouti, Abdelkarim Chaouiki, Young Gun Ko
Summary: Smart corrosion protection systems contribute significantly to extending a material's lifespan and reducing maintenance expenses by enabling the immediate detection of environmental changes. In this study, nanomagnetic polymer/Fe3O4 composites were developed as a self-healing corrosion inhibitor and tested as a coating on carbon steel. The results showed excellent corrosion inhibition performance and increased corrosion resistance with the addition of the composite to the paint.
APPLIED SCIENCES-BASEL
(2023)
Article
Engineering, Mechanical
Warda Bahanan, Siti Fatimah, Jae Hoon Go, Jeong Moo Oh, Min Jun Kim, Myung Jae Kim, Jee-Hyun Kang, Dong-Ju Kim, I. Putu Widiantara, Young Gun Ko
Summary: This study proposes a novel methodology that combines experimental investigations with finite element simulations to evaluate the reliability and validity of Al 3104 sheet metals in cold deep drawing. The influence of nose plunger radius and coefficient of friction at a fixed speed and temperature is examined, and five different scenarios are simulated to determine the optimal parameters. The results show that strain-based criteria are effective in characterizing deformation behavior, and the simulation data align well with the actual strain distributions during bending.