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, Electrical & Electronic
Zulfiqar, Muhammad Zubair, Aurangzeb Khan, Tang Hua, Nasir Ilyas, Simbarashe Fashu, Amir Muhammad Afzal, Main Akif Safeen, Rajwali Khan
Summary: The study found that the quantity of oxygen vacancies significantly influences the structure and properties of co-doped ZnO nanoparticles, increasing with dopant concentration. Furthermore, there is a strong correlation between oxygen vacancies and the enhanced dielectric and magnetization responses of Co (fixed) and Mn (varied) co-doped ZnO nanoparticles, making them suitable for spintronics and optoelectronic applications.
JOURNAL OF MATERIALS SCIENCE-MATERIALS IN ELECTRONICS
(2021)
Article
Materials Science, Multidisciplinary
Adil Murtaza, Wen-liang Zuo, Xianghao Song, Awais Ghani, Azhar Saeed, Muhammad Yaseen, Fanghua Tian, Sen Yang
Summary: This work reports on the robust ferromagnetism at room temperature in co-precipitation derived rare-earth (Tb) and transition metal (Co) co-doped ZnO nanoparticles. XRD analysis confirms the single-phase character, while morphological studies show the formation of spherical-shaped particles separated by well-defined grain boundaries. The increase in oxygen vacancies is confirmed through photoluminescence spectra. The (Tb, Co) co-doped NPs exhibit room temperature ferromagnetic behavior, which is discussed based on the role of oxygen vacancies and grain boundaries.
Article
Chemistry, Physical
Irshad Ahmad, Shazia Shukrullah, Muhammad Yasin Naz, Haq Nawaz Bhatti
Summary: This study investigates the impact of doping-induced oxygen vacancies, the formation of heterojunction, and the role of Tb4+/Tb3+ redox centers on the photo-activity of Sm-ZnO/ Y-Tb2O3 composite. The results show that these factors significantly enhance the photocatalytic activity of the composite material. The findings contribute to the design and construction of novel materials with strong photo-catalytic performance.
INTERNATIONAL JOURNAL OF HYDROGEN ENERGY
(2023)
Article
Chemistry, Physical
Yong-Hui Zhang, Ming-Xing Peng, Li-Juan Yue, Jun-Li Chen, Fei-Long Gong, Ke-Feng Xie, Shao-Ming Fang
Summary: The paper discusses the successful synthesis of Ce-doped ZnO porous nanosheets and their sensing properties towards aniline at room temperature. The Ce-doped ZnO sensor exhibited high response and excellent selectivity due to the abundant oxygen vacancies, high specific surface area, and interface interaction between CeO2 and ZnO. The DFT study results indicated enhanced interaction between ZnO and aniline by introducing oxygen vacancies and Ce doping, suggesting that CZO composites could be a potential candidate for aniline detection at room temperature.
JOURNAL OF ALLOYS AND COMPOUNDS
(2021)
Article
Chemistry, Multidisciplinary
Fatemah. H. Alkallas, Amira Ben Gouider Trabelsi, Ramzi Nasser, Susana Fernandez, Ji-Ming Song, Habib Elhouichet
Summary: Chromium-doped zinc oxide nanorods were prepared and their structural, morphological, and optical properties were studied. The doped nanorods showed efficient photocatalytic degradation of methyl orange under UV-vis light illumination.
APPLIED SCIENCES-BASEL
(2022)
Article
Chemistry, Physical
Dilawar Ali, M. Z. Butt, I Muneer, F. Bashir, M. Hanif, Taj M. Khan, Shahab Ahmed Abbasi
Summary: Highly c-axis oriented ZnO thin films with wurtzite structure were grown onto preheated glass using spray pyrolysis technique with varying Al/Zn ratios. The films exhibited good optical properties and antibacterial activity against Escherichia Coli bacteria, with enhanced efficacy on increasing Al/Zn ratio. These antimicrobial coatings have potential applications in surgical instruments, protective hospital apparels, medical implants, storage containers, textile, and food packs.
SURFACES AND INTERFACES
(2021)
Article
Nanoscience & Nanotechnology
Muhammad Hussain, Amjad Nisar, Shafqat Hussain, Lizhi Qian, Shafqat Karim, Yanguo Liu, Amina Zafar, Hongyu Sun, Mashkoor Ahmad
Summary: This study presents a vanadium-doped zinc oxide nanostructure with voltage switchable electrocatalytic properties for accurate measurements of glucose and hydrogen peroxide. The material's oxygen vacancies, controlled by stoichiometric ratios, play a crucial role in voltage-dependent measurements of different analytes. The developed nanostructures demonstrate outstanding sensing ability, high selectivity, low detection limit, thermal stability, and long-term stability. The results also show good response to human blood serum and commercially available samples.
Article
Chemistry, Multidisciplinary
Dimitrina Petrova, Blagovest Napoleonov, Chau Nguyen Hong Minh, Vera Marinova, Yu-Pin Lan, Ivalina Avramova, Stefan Petrov, Blagoy Blagoev, Vladimira Videva, Velichka Strijkova, Ivan Kostadinov, Shiuan-Huei Lin, Dimitre Dimitrov
Summary: In this paper, aluminum-doped zinc oxide (ZnO:Al or AZO) thin films were grown using atomic layer deposition (ALD), and the effects of postdeposition UV-ozone and thermal annealing treatments on the films' properties were investigated. X-ray diffraction (XRD) revealed a polycrystalline wurtzite structure with a preferable (100) orientation. Thermal annealing increased the crystal size, while UV-ozone exposure had no significant impact on crystallinity. X-ray photoelectron spectroscopy (XPS) analysis revealed a higher amount of oxygen vacancies in the ZnO:Al after UV-ozone treatment, while the ZnO:Al had lower oxygen vacancies after annealing. The important and practical applications of ZnO:Al were found, particularly for transparent conductive oxide layers with high tunability in electrical and optical properties after postdeposition treatment, especially UV-ozone exposure for reducing sheet resistance values. Meanwhile, UV-ozone treatment did not affect the polycrystalline structure, surface morphology, or optical properties of the AZO films.
Article
Chemistry, Inorganic & Nuclear
Ramachandrapanicker Devi Chandra, Lalan Veena, Kunnel Gopalan Gopchandran
Summary: Cobalt (Co)-doped ZnO nanoparticles were synthesized at 100°C using a simple chemical technique, resulting in nanoparticles with high crystallinity and reduced defect density. Co-doping suppressed oxygen-vacancy-related defects at lower doping densities, but increased defect density at higher doping densities. Co-doping was found to significantly suppress defects in ZnO for electronic and optoelectronic applications, as demonstrated by XPS, PL, electrical conductivity, and Mott-Schottky analysis. Photodetectors fabricated with Co-doped ZnO nanoparticles showed faster response time due to the reduced defect density.
INORGANIC CHEMISTRY
(2023)
Article
Engineering, Environmental
Liang Qi, Jiawei Jiang, Fei Xie, Yanhong Zhao, Lili Wan, Ying Sun, Changwei Lu
Summary: This study successfully synthesized Pd-based electrocatalysts by incorporating Fe-doped Nb2O5 with abundant oxygen vacancies, effectively promoting ethylene glycol oxidation. The introduction of Fe doping altered the electronic structure of Nb2O5 and decreased the d-band center of Pd, reducing the thermodynamic energy barrier. The Pd/FNO-2.5 catalyst demonstrated remarkable electrocatalytic performance with low initial potential and high mass activity.
CHEMICAL ENGINEERING JOURNAL
(2023)
Article
Chemistry, Physical
Rumin Liu, Liyan Zhao, Shikuan Yang, Jingwen Lin, Xu Wang, Dongliang Chen, Guanjin Lu, Hongwen Chen, Zhaoying Wang, Zhizhen Ye, Jianguo Lu
Summary: ZnO nanoshuttles were synthesized and designed to have three motion modes of shake, rotation, and translation in water. The asymmetrically distributed defects on the surface of ZnO nanoshuttles are responsible for the swimming modes. This study also demonstrates the versatility and openness of ZnO nanoshuttle micro-/nanomotors.
JOURNAL OF PHYSICAL CHEMISTRY C
(2023)
Article
Crystallography
Ruifeng Tian, Mingyan Pan, Qinglin Sai, Lu Zhang, Hongji Qi, Hany Fathy Mohamed
Summary: This paper investigates the effects of oxygen vacancy and gallium vacancy on the optical and scintillation properties of undoped beta-Ga2O3 crystal and 2.5 mol% Al doped gallium oxide. The results show that the absorption cutoff slightly blue shifts and the band gap increases after the introduction of Al element. The contribution of the decay time component increases significantly after Al doping, but the light yield of the beta-Ga2O3 crystal is reduced.
Article
Crystallography
Yuchuan Ding, Liyan Niu, Yong Chen, MaoHua Wang
Summary: Zinc oxide materials doped with varying carbon contents were successfully synthesized, resulting in ZnO samples with a hexagonal wurtzite structure. The crystallite size increased as the carbon doping increased. The sample size was approximately 400-500 nm, and the doped samples exhibited carbon microsphere adhesion. Furthermore, the optical band gap value decreased from 3.16 to 2.79 eV with increasing carbon doping, indicating a decreasing trend. Raman spectroscopy revealed that increased carbon doping led to a decrease in crystal quality and oxygen vacancy concentration. Photoluminescence spectroscopy showed that all ZnO samples contained oxygen vacancy defects and deep-level double ionized oxygen vacancies. The carbon-doped samples exhibited an increase in the proportion of interstitial zinc (Zn-i) defects and a decrease in the O-Zn concentration of substitutional defects.
CRYSTAL RESEARCH AND TECHNOLOGY
(2023)
Article
Crystallography
Muhammad Adil Mahmood, Rajwali Khan, Sattam Al Otaibi, Khaled Althubeiti, Sherzod Shukhratovich Abdullaev, Nasir Rahman, Mohammad Sohail, Shahid Iqbal
Summary: The impact of Co and Gd on the structural, magnetic, and dielectric properties of ZnO nanotubes synthesized by co-precipitation is studied. The results show that incorporating Co and Gd into ZnO decreases crystallinity while maintaining optimum orientation. Co and Gd doping does not affect the morphology of the nanotubes. Decreasing the frequency and concentration of Gd co-dopant leads to an increase in dielectric constant and loss values. The presence of doping results in an inversely proportional relationship between dielectric constant and ac electrical conductivity response. Co and Gd co-doped ZnO nanotubes exhibit ferromagnetic properties at 300K, with an increase in ferromagnetic response as Gd doping increases to 3% and a decrease with further Gd co-doping. Electrical conductivity of the same sample is superior to pure and low Gd doped ZnO, suggesting potential applications in spin-based electronics.
