Article
Materials Science, Ceramics
Chi-Chung Kei, Chih-Chieh Wang, Tsong-Pyng Perng
Summary: The study introduces a novel method to prepare an Al-doped ZnO nanotube oxygen sensor with tunable wall thickness, using tris(8-hydroxyquinoline) gallium nanowire as a template. The research shows that the gas response of the nanotubes is inversely proportional to wall thickness and is influenced by the Al2O3 content.
JOURNAL OF THE AMERICAN CERAMIC SOCIETY
(2021)
Article
Materials Science, Multidisciplinary
Sanjaya Brahma, P. C. Huang, B. W. Mwakikunga, V. Saasa, A. A. Akande, Jow-Lay Huang, Chuan-Pu Liu
Summary: This study demonstrates the gas sensing properties of Cd-doped ZnO nanorods at room temperature and low temperature. The Cd doping in ZnO nanorods enhances the overall sensitivity to NH3 gas, with the highest sensitivity observed at a Cd doping concentration of 0.5 at %. The sensitivity continues to increase with the increase of temperature, indicating a significant enhancement of gas sensing performance at high temperature. Cd-doped ZnO nanorods also exhibit superior specificity for detecting NH3 over other gases such as NO2 and H2S at room temperature.
MATERIALS CHEMISTRY AND PHYSICS
(2023)
Article
Chemistry, Analytical
Yan Gong, Xiaofeng Wu, Xiaofei Li, Anqi Wang, Min Zhang, Yunfa Chen
Summary: Core-shell Pt@Al-doped ZnO nanoparticles were synthesized and assembled into a sensor, showing excellent sensitivity and low detection limit towards acetone. The synergistic effect between Al doping and metal-ZnO hetero-interfaces significantly improves the acetone sensing properties of the sensor.
SENSORS AND ACTUATORS B-CHEMICAL
(2021)
Article
Engineering, Electrical & Electronic
Onur Alev, Imren Erguen, Okan Oezdemir, Leyla Colakerol Arslan, Serkan Bueyuekkoese, Zafer Ziya Ozturk
Summary: Cu-doped ZnO nanorods showed enhanced sensor response towards ethanol and allowed operation at lower temperatures compared to pristine ZnO nanorods, with 2% and 3% Cu-doped sensors exhibiting selective behavior towards ethanol.
MATERIALS SCIENCE IN SEMICONDUCTOR PROCESSING
(2021)
Article
Engineering, Electrical & Electronic
Zixuan Li, Zhihua Lai, Zhen Zhao, Lei Zhang, Wanli Jiao
Summary: Pure ZnO and Nd2O3-doped ZnO nanoparticles were synthesized using a hydrothermal method and characterized by XRD, SEM, and XPS. The doping of Nd promoted the growth of short columnar ZnO crystal and caused structural defects. The substitution of Nd3+ with Zn2+ resulted in a large amount of oxygen vacancies, enhancing the adsorption of oxygen molecule. The doped ZnO exhibited excellent sensitivity to H2S, with a response of 242-10 ppm H2S at 150 degrees C and a lowest detection limit of 50 ppb.
SENSORS AND ACTUATORS A-PHYSICAL
(2023)
Article
Materials Science, Multidisciplinary
Zhaohua Wang, Mingfeng Zhi, Manzhang Xu, Chen Guo, Zhenwu Man, Zhiyong Zhang, Qiang Li, Yuanyuan Lv, Wu Zhao, Junfeng Yan, Chunxue Zhai
Summary: Sb-doped SnO2/ZnO nano-heterojunctions were prepared using a microwave hydrothermal method, and the effects of Sb-doping on the morphology and gas sensor performance of SnO2/ZnO NHs were studied in detail. The study found that Sb-doping changed the morphology of SnO2 and enhanced the gas sensor response.
JOURNAL OF MATERIALS SCIENCE
(2021)
Article
Engineering, Electrical & Electronic
V. L. Patil, D. S. Dalavi, S. B. Dhavale, N. L. Tarwal, S. A. Vanalakar, A. S. Kalekar, J. H. Kim, P. S. Patil
Summary: This report focuses on the deposition of nanocrystalline aluminium doped ZnO (Al doped ZnO: AZO) samples on seeded glass substrates using a cost-effective reflux method. The doping concentration of 'Al' ions ranged from 1 to 3 vol%. The study found that the deposited AZO samples exhibited a wurtzite hexagonal crystal structure and the formation of nanorods for undoped ZnO, with a reduction in diameter and the formation of fine tips for AZO samples. The photoluminescence study confirmed the presence of oxygen vacancies and defects in the AZO samples. Furthermore, the AZO samples demonstrated excellent gas sensing performance towards NO2 gas at a temperature of 175 degrees C, with a gas sensitivity of 85% for 5 ppm NO2 gas. This work shows promise for practical applications in the gas sensor technology field, particularly for low detection limits at low operating temperatures.
SENSORS AND ACTUATORS A-PHYSICAL
(2022)
Article
Engineering, Environmental
Jian Fang, Jing-Jing Xue, Rong-Pu Xiao, Xi Chen, You-Min Guo, Ji-Ming Song
Summary: This study reported a gas sensor based on Pr-doped ZnO nanospindles for the detection of triethylamine (TEA). Among the different doping concentrations, the 2 mmol% Pr-ZnO sensor exhibited the highest response value towards TEA gas. The sensor showed good reproducibility, rapid response/recovery time, theoretical limit of detection, outstanding long-term stability, and excellent selectivity for TEA gas.
JOURNAL OF ENVIRONMENTAL CHEMICAL ENGINEERING
(2022)
Article
Chemistry, Physical
Kuo-Chin Hsu, Te-Hua Fang, Yu-Jen Hsiao, Zong-Jin Li
Summary: CuO-doped ZnO heterojunction nanofibers were successfully prepared using sol-gel and electrospinning methods. The sensing response of H2S was significantly enhanced when the mole ratio of CuO to ZnO was 0.15:1, reaching a best gas response of 83.98% at 1 ppm H2S.
JOURNAL OF ALLOYS AND COMPOUNDS
(2021)
Article
Chemistry, Inorganic & Nuclear
Sahar Imeni, Morteza Rouhani, Javad Mokhtari Aliabad
Summary: In this study, the capability of NiN4S-doped single wall carbon nanotube (NiN4S-doped SWCNT) as a sensor material for detecting H2 gas at room temperature was investigated and compared with pristine single wall carbon nanotube (SWCNT). The results showed that the adsorption capacity of H2 on NiN4S-doped SWCNT was significantly improved compared to pristine SWCNT. It was found that the adsorption occurred via typical van der Waals interactions. Therefore, NiN4S-doped SWCNT can be considered as an ultrafast and efficient material for H2 sensing.
INORGANIC CHEMISTRY COMMUNICATIONS
(2023)
Article
Optics
Haitham T. Hussein, Muna H. Kareem, Adi M. Abdul Hussein
Summary: This study prepared a high-quality gas sensor by adding carbon nanotubes and zinc oxide nanoparticles doped with porous silicon layers. The CNTs-ZnO/PS sample showed the highest sensitivity to ethanol gas, reaching 2.004984 at a concentration of 500 ppm, demonstrating excellent sensing ability.
Article
Engineering, Electrical & Electronic
Chu Manh Hung, Han Viet Phuong, Vu Van Thinh, Le Thi Hong, Nguyen Tat Thang, Nguyen Hong Hanh, Nguyen Quang Dich, Nguyen Van Duy, Nguyen Van Hieu, Nguyen Duc Hoa
Summary: The nanofibers of ZnO-SnO2 nanocomposites doped with Au crystals were successfully synthesized using electrospinning method, leading to a significant enhancement in gas sensing performance towards H2S gas. The doping of Au crystals on the surface of nanofibers improved the effective surface catalyzed gas reaction, resulting in approximately 700% improvement in gas sensitivity towards H2S gas.
SENSORS AND ACTUATORS A-PHYSICAL
(2021)
Article
Nanoscience & Nanotechnology
Seung-Eun Baek, Dahl-Young Khang
Summary: Selective growth of ZnO nanorods has been achieved by exploiting the thickness contrast and grain size variation in the IZO QD seed layer, leading to improved sensor performance.
Article
Chemistry, Analytical
Yue Xing, Le-Xi Zhang, Meng-Xiao Chong, Yan-Yan Yin, Cheng-Tao Li, Li-Jian Bie
Summary: Pure ZnO and carbon-doped ZnO hollow spheres were successfully synthesized via a hydrothermal-calcination process. The carbon doping introduced abundant defects in the mesoporous ZnO hollow spheres, leading to enhanced gas sensing performance towards dimethylamine. The response of ZnO-600 towards 200 ppm dimethylamine was significantly higher than that of Pure ZnO and ZnO-500, and the detection limit was as low as 108 ppb. The unique mesoporous microstructure and rich defects induced by in-situ carbon doping contributed to the improved sensing performance of ZnO-600.
SENSORS AND ACTUATORS B-CHEMICAL
(2022)
Article
Chemistry, Analytical
Seyeon Park, Peresi Majura Bulemo, Won-Tae Koo, Jaehyun Ko, Il-Doo Kim
Summary: By utilizing solid-solution doping and catalytic metal nanoparticles, superior acetylene sensing capabilities were achieved through porous metal oxide nanofibers. The high porosity of the metal oxide nanofibers, prepared using electrospinning and sacrificial templating, was essential for high gas permeability and active sites. Ga-doped ZnO porous NFs functionalized with Pt catalysts demonstrated the highest C2H2 sensing responses with exceptional selectivity and stability against interfering gases.
SENSORS AND ACTUATORS B-CHEMICAL
(2021)
Article
Polymer Science
Saheed O. Oseni, Olawale L. Osifeko, Adenike O. Boyo, Genene Tessema Mola
Summary: CdTeSe colloidal quantum dot (QD) is used to enhance photon capture in thin film polymer solar cells (TFPSC). The addition of QD at different concentrations in the polymer matrix significantly impacts the power conversion efficiency (PCE) of the doped devices. By using solvent additives to disperse the QDs and increase the polymer's crystallinity, the overall performance of the TFPSC is further enhanced.
JOURNAL OF APPLIED POLYMER SCIENCE
(2023)
Article
Materials Science, Multidisciplinary
Sohail Ahmed, Peter P. P. Murmu, Clastinrusselraj Indirathankam Sathish, Xinwei Guan, Rex Geng, Nina Bao, Rong Liu, John Kennedy, Jun Ding, Mingli Peng, Ajayan Vinu, Jiabao Yi
Summary: Magnetic 2D-layered materials have great potential for spintronic devices and compact magnetic devices. Introducing a magnetic element into 2D-layered materials is an effective strategy to synthesize magnetic materials. By ion implantation, Co and Nd were codoped into MoS2 crystals, achieving extremely high magnetization at both low and room temperatures. This study opens up a useful strategy to develop high-performance magnetic materials based on 2D-layered materials.
PHYSICA STATUS SOLIDI-RAPID RESEARCH LETTERS
(2023)
Article
Chemistry, Multidisciplinary
G. G. Welegergs, H. G. Gebretinsae, M. G. Tsegay, Christopher Mtshali, Nametso Mongwaketsia, Karen Cloete, Z. Y. Nuru, S. Dube, M. Maaza
Summary: Spectrally selective single-layered CuO nanocoatings were successfully synthesized and deposited on stainless steel substrates via spin coating at different rotational speeds. The morphology, structure, and composition of the nanocoatings were analyzed using SEM, XRD, EDX, and Raman spectroscopy. The nanocoatings exhibited nanorod-like structures with dense surface morphology, monoclinic CuO phase, and characteristic peaks of Cu (II) and O (II). The thicknesses of the coatings varied with the rotational speed of the spin coater, and the elemental content of Cu and O atoms was determined to be 54% and 46%, respectively. The CuO nanocoatings showed excellent solar selectivity parameters (alpha = 0.90 and epsilon = 0.31) at 700 rpm, attributed to intrinsic and interference-induced absorption as well as higher attenuation of light.
APPLIED SCIENCES-BASEL
(2023)
Review
Materials Science, Multidisciplinary
Benjamin O. Orimolade, Azeez O. Idris, Seyi Philemon Akanji, Folahan A. Adekola, Shohreh Azizi, Malik Maaza, Bhekie Mamba
Summary: Due to the increasing demand for cleaner water, nanomaterials have been used in wastewater treatment application, especially in photoelectrocatalytic (PEC) degradation. This process combines light and electrical energy to achieve total mineralisation of organic pollutants in wastewater. Nanostructured photoanodes with distinct morphologies have greatly enhanced the efficiency of PEC degradation, leading to the removal of pharmaceuticals, dyes, and phenolic water from wastewater within a short time period. This review provides an overview of the successful use of nanostructured photoanodes in PEC degradation, along with the techniques employed to improve their solar light responsiveness.
Article
Engineering, Electrical & Electronic
H. F. Haji, N. Numan, I. G. Madiba, B. Mabakachaba, C. Mtshali, Z. Khumalo, L. Kotsedi, N. Mlyuka, M. Samiji, M. Maaza
Summary: In this study, un-doped VO2, tungsten (W)-doped VO2, and W/Zn co-doped VO2 thin films were prepared and characterized. Results showed that co-doping with W and Zn in VO2 films increased their solar transmittance modulation to 4% and luminous transmittance to approximately 46%, while lowering the transition temperature to below 27 degrees C. These findings suggest that combined doping with W and Zn could make VO2 films suitable for smart window applications.
JOURNAL OF ELECTRONIC MATERIALS
(2023)
Article
Chemistry, Analytical
Anmol Mahendra, Peter P. Murmu, Susant Kumar Acharya, Atif Islam, Holger Fiedler, Prasanth Gupta, Simon Granville, John Kennedy
Summary: In this study, the perpendicular magnetic anisotropy (PMA) of Co2MnGa Heusler alloy film was tuned by argon ion irradiation. The results showed that ion irradiation reduced the effective anisotropy energy and PMA of the film, which is beneficial for magnetic sensor applications.
Article
Materials Science, Multidisciplinary
Abdelaziz Ait Abdelkadir, Jean-Louis Victor, Guillaume Vignaud, Corinne Marcel, Mustapha Sahal, Malik Maaza, Mohamed Chaker, Alain Gibaud
Summary: In this paper, the optical and structural properties of undoped and W-doped V1-xWxO2 vanadium dioxide thin films were investigated. X-ray diffraction analysis showed the transition from monoclinic to rutile phase and a coexistence of phases for tungsten-doped VO2. The study also revealed the decrease of transition temperature from 69.6°C to 41.6°C with increasing tungsten concentration.
Article
Materials Science, Multidisciplinary
P. Gupta, V. Jovic, R. Huebner, E. Anquillare, K. Suschke, K. E. Smith, A. Markwitz, G. I. N. Waterhouse, J. Kennedy
Summary: A one-step approach to synthesize ultrafine metallic cobalt nanoparticles at room temperature by cobalt ion implantation into amorphous carbon films and hydrogenated amorphous carbon films was explored. It was found that hydrogenated carbon films suppressed the aggregation of metallic cobalt nanoparticles, leading to the formation of ultrafine cobalt nanoparticles with a size smaller than 5 nm.
MATERIALS TODAY COMMUNICATIONS
(2023)
Article
Materials Science, Multidisciplinary
I. Ngom, N. M. Ndiaye, N. F. Sylla, S. Dieng, B. D. Ngom, M. Maaza
Summary: Three aqueous solutions derived from Moringa oleifera (M.O) flowers, seeds, and leaves were used for the biosynthesis of nickel oxide nanoparticles (NiO-NPs). These nanoparticles were characterized by X-ray diffraction, Fourier-transform infrared spectroscopy, and Raman spectroscopy, and were found to crystallize in a face centered-cubic single Bunsenite phase. NiO@flowers had the smallest average crystallite size of 18.5 nm, while NiO@seeds had 29.0 nm and NiO@leaves had 21.7 nm. Scanning electron microscopy revealed that NiO@flowers had non-uniform, spherically agglomerated nano-crystals, while NiO@seeds had highly coalescent nanograins and NiO@leaves had irregularly connected microcavities with small nanograins.
Article
Materials Science, Multidisciplinary
Razieh Morad, Mahmood Akbari, Malik Maaza
Summary: This study uses density functional theory calculations to investigate the chemical reactivity descriptors of proposed drugs for COVID-19. The structure optimization and analysis of frontier orbitals reveal the importance of the highest occupied molecular orbital (HOMO) and the lowest unoccupied molecular orbital (LUMO) in molecular interactions and reactivity. The polarizability is higher in complex drugs such as Hydroxychloroquine, Remdesivir, and Ivermectin, and the calculated energy gap suggests that larger gaps correspond to lower reactivity and higher stability.
Article
Chemistry, Multidisciplinary
Innocent C. Nwodo, Agnes C. Nkele, Raphael M. Obodo, Jude N. Udeh, Princess C. Ani, Chinedu P. Chime, M. Maaza, Fabian I. Ezema
Summary: This study investigated the characteristics of nickel phosphate nanoparticles co-precipitated at varying molar concentrations in terms of structure, morphology, elements, optics, and electrochemistry. The results showed a monoclinic crystalline phase and nanorod morphology. EDX confirmed the presence of nickel, phosphorus, and oxygen. The films exhibited good absorbance and had optical energy band gap values ranging from 1.58 eV to 2.2 eV. They also showed good cyclic reversibility as electrolytes. The specific capacitance values of the electrodes ranged from 624.38 F/g to 1017.2 F/g at a scan rate of 1 mV/s. The Ni3(PO4)2 electrode prepared at 0.3 M showed the highest energy and power densities of 239.49 Wh/kg and 2.52 W/kg, respectively. These synthesized samples have potential applications in optical and electrochemical devices.
JOURNAL OF THE INDIAN CHEMICAL SOCIETY
(2023)
Article
Agriculture, Multidisciplinary
Haripriya Rama, Busiswa Ndaba, Malik Maaza, Mokhotjwa Simon Dhlamini, Nicolene Cochrane, Ashira Roopnarain
Summary: This study aimed to investigate the effect of different extraction methods on the recovery of phytochemicals and antioxidants from de-kernelled marula seeds. The results showed that the decoction method for 30 minutes produced extracts with the highest content of phenolic compounds, flavonoids, sugars, and organic acids. Fourier-transform infrared spectroscopy confirmed the presence of functional groups typically present in these compounds. The study concluded that the decoction method increased the solubility, variety, and yield of phytochemicals and antioxidants, potentially paving the way for their utilization in the food industry. Rating: 8/10
JOURNAL OF THE SCIENCE OF FOOD AND AGRICULTURE
(2023)
Review
Environmental Sciences
Benjamin O. Orimolade, Adewale O. Oladipo, Azeez O. Idris, Feleni Usisipho, Shohreh Azizi, Malik Maaza, Sogolo L. Lebelo, Bhekie B. Mamba
Summary: In recent years, there has been a focus on making water safer and cleaner by eliminating pharmaceutical residues, particularly fluoroquinolone antibiotics, from wastewater. Electrochemical technologies, such as photoelectrocatalysis, electro-Fenton, electrocoagulation, and electrochemical oxidation, have been found to be effective in removing these pharmaceuticals from wastewater. This review discusses the recent progress in the application of these electrochemical processes for the degradation of fluoroquinolone antibiotics, highlighting their fundamentals, results, advantages, limitations, and recommendations for future improvements. It serves as a valuable resource for researchers in the selection of suitable electrochemical techniques for pharmaceutical removal from wastewater.
SCIENCE OF THE TOTAL ENVIRONMENT
(2023)
Article
Chemistry, Multidisciplinary
Holger Fiedler, Niall Malone, David R. G. Mitchell, Mitchell Nancarrow, Vedran Jovic, Geoffrey I. N. Waterhouse, John Kennedy, Prasanth Gupta
Summary: Molybdenum carbides are potential low-cost electrocatalysts for electrolyzers, fuel cells, and batteries. This study presents a scalable, physical approach to synthesize molybdenum carbide nanoparticles at room temperature by ion implantation, with the ability to control the phase, stoichiometry, and size of the nanoparticles. The results are explained using the Mo-C phase diagram and Monte-Carlo simulations, and the approach can be applied to synthesize other transition metal carbide nanoparticles.
Article
Multidisciplinary Sciences
Shohreh Azizi, Maryam Sarkhosh, Ilunga Kamika, Touhami Mokrani, Malik Maaza
Summary: The study examined the cost-effective degradation of trimipramine (TIR) using UV/Sulfite/ZnO (USZ) in both conventional and baffled photocatalytic reactors (BPCR). The optimal conditions for high TRI degradation (97.4%) were a 2:1:100 Sulfite/ZnO/TRI molar ratio, pH 7, and a 30-minute reaction time. In the BPCR reactor, the measured rate constant (k(obs)) and reaction rate (r(obs)) increased by approximately 17% and 50% respectively, as the TRI concentration increased. The intermediate materials formed were analyzed, and most of them were found to be simple linear compounds. The introduction of baffles in the reactor led to decreased electrical energy consumption and total system cost, while the UZS procedure effectively reduced BOD and COD levels.
ARABIAN JOURNAL FOR SCIENCE AND ENGINEERING
(2023)
