Article
Engineering, Electrical & Electronic
Zhoubin Boroun, Mohammad Ghorbani, Raheleh Mohammadpour, Ali Moosavi
Summary: Metal-oxide gas sensors, particularly the SnO2-CuO system, are widely used for detecting H2S gas. While the previous 2D thin bilayer model explained some aspects of the sensor's performance, experimental research showed that multicomponent heterostructures have higher response. By introducing an n-p-n junction in a 3D model, the sensitivity of the sensor element towards H2S gas significantly improved, indicating the potential for optimized sensor fabrication.
IEEE SENSORS JOURNAL
(2021)
Article
Physics, Applied
D. Verheij, M. Peres, S. Cardoso, L. C. Alves, E. Alves, C. Durand, J. Eymery, J. Fernandes, K. Lorenz
Summary: Self-powered particle detectors based on GaN core/shell p-n junction microwires offer exceptional flexibility and compactness in applications where size limits and low power consumption are key requisites. These microwires demonstrate high resistance to radiation and high crystalline quality, making them interesting building blocks for radiation-hard devices. Despite a small increase in leakage current after prolonged proton irradiation, the transient ionocurrent signal remains stable during irradiation with a total proton fluence of at least 1 x 10(16) protons/cm(2).
APPLIED PHYSICS LETTERS
(2021)
Article
Chemistry, Physical
Orhan Sisman, Dario Zappa, Valentin-Adrian Maraloiu, Elisabetta Comini
Summary: The study proposes an inverse design by depositing n-type ZnO shell layers on the surface of p-type CuO core-shell nanowires to understand their conductometric gas-sensing kinetics. The surface morphologies of bare and core-shell nanowires were investigated using FE-SEM. The ZnO shell layer was observed using EDX and HRTEM techniques. The deposition of ZnO shell layers switched the intrinsic p-type sensing behavior of CuO nanowires towards hydrogen to n-type.
Review
Nanoscience & Nanotechnology
Yujie Zhang, Pengjie Zhang, Shouzhe Feng, Jun Cao, Jingjing Wang, Yingying Zheng, Lei Shi, Chaorong Li, Jiaqi Pan
Summary: A Cu2O/ZnS/ZnO core-shell orderly nanoarray transparent p-n junction was prepared through a hydrothermal in situ sulfuration-sputtering method. The Cu2O/ZnS/ZnO exhibited higher transmittance, photovoltaic enhancement, and stable output. The in situ dual functional ZnS transition layer, better carrier transport pathway, and increased physical and chemical stability of the ZnS/ZnO nanoarrays all contributed to the improved performance.
ACS APPLIED NANO MATERIALS
(2023)
Article
Chemistry, Analytical
Peng He, Haitao Fu, Yanlong Gong, Jie Chen, Xiaohong Yang, Dezhi Han, Shixian Xiong, Song Li, Xizhong An
Summary: In order to detect flammable gases and reduce energy consumption, room-temperature gas sensors with high sensitivity, selectivity, and stability have become increasingly popular. In this study, SnO2@ZnS core-shell hollow spheres were prepared using a two-step hydrothermal method. The effects of morphology and composition on gas sensing performance were investigated by adjusting the molar ratio of SnO2 to ZnS. The core-shell composites showed excellent sensing properties to n-butanol, with a sensing response four times higher than that of the pristine SnO2 hollow spheres.
SENSORS AND ACTUATORS B-CHEMICAL
(2023)
Article
Chemistry, Physical
Cheng-Liang Hsu, En-Cheng Chang, Han-Ting Hsueh, Yi-Hung Liu
Summary: The study successfully synthesized n-ZnO/p-CuMnO2 core-shell nanowires by solution method, exhibiting good rectification and ultra-low leakage properties, as well as sensitivity and rapid response to organic gases and light of different wavelengths.
JOURNAL OF ALLOYS AND COMPOUNDS
(2022)
Article
Chemistry, Analytical
Dong Jae Yu, Wansik Oum, Ali Mirzaei, Ka Yoon Shin, Eun Bi Kim, Hyeong Min Kim, Sang Sub Kim, Hyoun Woo Kim
Summary: We synthesized pristine SnO2 nanoparticles and Au@SnO2 core-shell nanocomposites for xylene gas sensing. The Au@SnO2 core-shell nanocomposites showed better response and selectivity compared to the pristine SnO2 nanoparticles, demonstrating the promising effects of the Au@SnO2 core-shell structure for xylene sensing.
SENSORS AND ACTUATORS B-CHEMICAL
(2023)
Article
Chemistry, Multidisciplinary
Muhammad Hamid Raza, Navpreet Kaur, Elisabetta Comini, Nicola Pinna
Summary: In this study, 1D SnO2-SiO2 core-shell nanowires were introduced, showing enhanced selectivity and sensitivity towards hydrogen gas sensing. The thickness of the SiO2 shell and working temperature were strongly correlated with the sensing response.
ADVANCED MATERIALS INTERFACES
(2021)
Article
Chemistry, Physical
Lang He, Wenyuan Zhang, Kristin Zhao, Sheng Liu, Yan Zhao
Summary: A facile method was used to fabricate 3D nitrogen-doped graphitic carbons with embedded core-shell nanoparticles. These materials showed excellent photocatalytic activity and could be used for the design and synthesis of high-efficiency core-shell photocatalysts.
JOURNAL OF MATERIALS CHEMISTRY A
(2022)
Article
Chemistry, Physical
Sourav Kumar Kajli, Debdutta Ray, Somnath C. Roy
Summary: One-dimensional nanostructures such as nanowires exhibit enhanced photoresponse compared to bulk materials due to unidirectional transport reducing recombination and scattering of charge carriers. CuO and Cu2O are promising transition metal oxides for efficient UV and visible light detection, forming type-II heterojunction for charge separation. Core-shell CuO/Cu2O nanowires show superior performance in terms of responsivity and detectivity, attributed to the Ohmic junction at Pd-Cu2O interface and type II heterojunction at CuO/Cu2O interface.
JOURNAL OF ALLOYS AND COMPOUNDS
(2022)
Article
Physics, Applied
Jialin Wang, Jiaxun Song, Ling Qin, Yingchun Peng, Richard Notzel
Summary: The researchers have successfully developed an efficient self-powered photoelectrochemical photodetector using a core-shell nanowire design. The photocurrent density is significantly enhanced, and the response time is short, achieving one of the shortest response times among similar devices. It also exhibits long-time stability and reusability.
APPLIED PHYSICS LETTERS
(2022)
Article
Nanoscience & Nanotechnology
Xiaoyan Song, Fangzheng Zhao, Zhipeng Wang, Runbin Ge, Jinfeng Xing
Summary: In this study, ZnO@SnO2-Pt core-shell nanofibers with a hollow structure were successfully prepared and exhibited superior gas-sensing performance, achieving higher response speed and sensitivity on the basis of reduced operating temperature. Additionally, the gas-sensing mechanism of the nanofibers was discussed in detail.
ACS APPLIED NANO MATERIALS
(2022)
Article
Chemistry, Physical
Anna Baranowska-Korczyc, Ewelina Mackiewicz, Katarzyna Ranoszek-Soliwoda, Jaroslaw Grobelny, Grzegorz Celichowski
Summary: This study introduces core/shell Ag/SnO2 nanowires as a new photocatalyst for the rapid degradation of organic compounds under visible light. The efficient degradation process is attributed to the unique properties of Ag/SnO2 nanowires, including surface plasmon resonance effects and charge separations preventing recombination of electron-hole pairs. These properties make Ag/SnO2 nanowires suitable for designing efficient and fast photodegradation systems for organic pollutants under solar light.
Article
Physics, Multidisciplinary
Yingzhi Zhao, Lingyun Xie, Hedong Chen, Xingyu Wang, Yongjie Chen, Guofu Zhou, Richard Notzel
Summary: The novel n-InGaN/p-Cu2O nanowire photoanode, obtained through heterostructuring and doping concepts, significantly enhances the photocurrent for solar water splitting. The optimized core-shell structure, self-stabilized at positive voltage, combined with a NiOOH co-catalyst, boosts the photocurrent into a competitive range.
FRONTIERS IN PHYSICS
(2021)
Article
Environmental Sciences
Mengmeng Zhan, Chuanxin Ge, Shahid Hussain, Ali S. Alkorbi, Raiedhah Alsaiari, Nabil A. Alhemiary, Guanjun Qiao, Guiwu Liu
Summary: Timely detection of harmful, poisonous, and air pollutant gases is crucial for protecting humans from exposure to severe gas levels. Gas-sensing devices based on sphere-like porous SnO2/ZIF-8 nanocomposites provide high surface area, porosity, and active sites for excellent responses in metal oxide gas sensors. The engineered gas sensors show excellent sensing sensitivity, rapid response and recovery times, and favorable selectivity for NO2 gases. Therefore, NO2 gas sensors based on core-shell SnO2/ZIF-8 nanospheres have promising applications in industrial settings.
Article
Chemistry, Analytical
Jae-Hyoung Lee, Ali Mirzaei, Jae-Hun Kim, Jin-Young Kim, Abulkosim F. Nasriddinov, Marina N. Rumyantseva, Hyoun Woo Kim, Sang Sub Kim
SENSORS AND ACTUATORS B-CHEMICAL
(2020)
Article
Engineering, Electrical & Electronic
Jae-Hun Kim, Ali Mirzaei, Hyoun Woo Kim, Sang Sub Kim
SENSORS AND ACTUATORS A-PHYSICAL
(2020)
Article
Chemistry, Analytical
Jae-Hun Kim, Ali Mirzaei, Hyoun Woo Kim, Sang Sub Kim
SENSORS AND ACTUATORS B-CHEMICAL
(2020)
Article
Chemistry, Analytical
Jae-Hun Kim, Jin-Young Kim, Jae-Hyoung Lee, Ali Mirzaei, Hyoun Woo Kim, Shunich Hishita, Sang Sub Kim
SENSORS AND ACTUATORS B-CHEMICAL
(2020)
Article
Multidisciplinary Sciences
Jae-Hun Kim, Jae-Hyoung Lee, Ali Mirzaei, Hyoun Woo Kim, Boon Teoh Tan, Ping Wu, Sang Sub Kim
SCIENTIFIC REPORTS
(2020)
Article
Engineering, Environmental
Jae-Hun Kim, Ali Mirzaei, Jae Hoon Bang, Hyoun Woo Kim, Sang Sub Kim
Summary: The study investigated the effects of SnO2 shell thickness and operating voltage on the sensing behavior of WS2 nanosheets, finding that a 15 nm thick shell at 3.4 V was optimal for CO sensing, while a 30 nm thick shell was optimal for NO2 sensing. The engineering design principles can be used to selectively detect reducing gases like CO.
JOURNAL OF HAZARDOUS MATERIALS
(2021)
Article
Chemistry, Analytical
Jae-Hun Kim, Ali Mirzaei, Minoru Osada, Hyoun Woo Kim, Sang Sub Kim
Summary: The study utilized pristine and Pd-decorated 2D ZnO nanosheets for hydrogen detection, showing positive effects of Pd decoration on response, sensing temperature, and selectivity. Gas sensing experiments demonstrated that the Pd-decorated nanosheet sensor successfully detected low concentrations of hydrogen gas and could also detect hydrogen in a gaseous mixture with benzene. Furthermore, the presence of Pd-ZnO heterojunctions, formation of PdHx, and high catalytic activity of Pd were found to contribute to the sensing enhancement of the Pd-decorated sensor.
SENSORS AND ACTUATORS B-CHEMICAL
(2021)
Article
Chemistry, Analytical
Jae-Hun Kim, Jin-Young Kim, Ali Mirzaei, Hyoun Woo Kim, Sang Sub Kim
Summary: In this study, researchers fabricated WS2 nanosheets decorated with different materials on flexible substrates for CO gas sensing. The sensors exhibited unique responses and high selectivity to CO gas, with the Au-SnO2-co-decorated WS2 nanosheet sensor showing the highest response and selectivity. The presence of Au-WS2 Schottky junctions, SnO2-WS2 heterojunctions, and the catalytic role of Au nanoparticles in sensing CO gas were key factors contributing to the sensor's performance.
SENSORS AND ACTUATORS B-CHEMICAL
(2021)
Article
Chemistry, Analytical
Jae-Hun Kim, Hyoungwon Park, Ali Mirzaei, Myung Gwan Hahm, Sanghoon Ahn, Marcus Halik, Changkyoo Park, Sang Sub Kim
Summary: Generating oxygen vacancies on SnO2 nanowires by femtosecond laser irradiation can enhance gas sensing properties, improving response to NO2 and toluene gases. Lower laser pulse energy leads to better sensing performance.
SENSORS AND ACTUATORS B-CHEMICAL
(2021)
Article
Materials Science, Ceramics
Jae-Hun Kim, Ali Mirzaei, Jae-Hyoung Lee, Jin-Young Kim, Ping Wu, Hyoun Woo Kim, Sang Sub Kim
Summary: The study investigated the performance of electrowetting-on-dielectric (EWOD) devices using micro-nano hierarchical structures of SiO2 layers with pristine and noble metal decorations through the entropy wetting model. The noble metal-decorated layers showed improved EWOD properties at 200 V. The results provide insights into the behavior of droplets on various surfaces.
CERAMICS INTERNATIONAL
(2021)
Article
Chemistry, Multidisciplinary
Hyoungwon Park, Jae-Hun Kim, Dustin Vivod, Sungil Kim, Ali Mirzaei, Dirk Zahn, Changkyoo Park, Sang Sub Kim, Marcus Halik
Summary: This study enhanced the sensing capabilities of semiconducting metal oxide-based gas sensors through a new post-modification method, improving gas selectivity; the chemical-affinity-driven interaction between SAM and gas molecules enabled selective gas sensing.
Article
Chemistry, Analytical
Jae-Hun Kim, Ali Mirzaei, Jin-Young Kim, Dong-Hoon Yang, Sang Sub Kim, Hyoun Woo Kim
Summary: In this study, 2D pristine and Au-decorated WS2-SnO2 core-shell nanosheets were successfully synthesized for highly sensitive CO gas sensing applications. The gas sensors showed very low applied voltage and high performance, with no significant degradation in sensing performance after 10,000 bending cycles, demonstrating great potential for commercial applications.
SENSORS AND ACTUATORS B-CHEMICAL
(2022)
Article
Chemistry, Analytical
Jae-Hun Kim, Isao Sakaguchi, Shunich Hishita, Taku T. Suzuki, Noriko Saito
Summary: A new ternary structure was designed to enhance the sensing properties of WS2 nanosheet-based gas sensors at room temperature in self-heating mode. SnO2 nanowires were added to WS2 nanosheets and Au nanoparticles were deposited on the surface of the resulting composites. The presence of SnO2 nanowires effectively enhanced the diffusion and adsorption of gas species, while the chemical sensitization of Au contributed to an enhanced response to CO gas. The results showed the potential of the Au-decorated SnO2-WS2 as a low-power, low-voltage CO gas sensor in wet environments.
Article
Chemistry, Analytical
Hyoungwon Park, Jae-Hun Kim, Won-Sang Shin, Ali Mirzaei, Yoon-Jun Kim, Sang Sub Kim, Marcus Halik, Changkyoo Park
Summary: This study proposes an effective strategy to improve the selectivity and response of SnO2 nanowire-based gas sensors by adopting self-assembled monolayer functionalization and post-treatment femtosecond laser irradiation. The functionalization enhances gas selectivity by tuning surface chemical states, while the laser irradiation creates embossing surfaces and twin structures, improving gas adsorption and response.
SENSORS AND ACTUATORS B-CHEMICAL
(2022)
Article
Materials Science, Multidisciplinary
Minsu Lee, Hohyeong Kim, Hyungsub Kim, Akash Katoch, Jae Young Park
Summary: This study investigated the effect of the mixing ratio of TiO2 nanoparticles (P25) and titanium alkoxide (T-sol) on various properties of TiO2 films. The specific surface area, microstructure, thickness, transmittance, pencil hardness, and oil contact angle of the films were analyzed. The results showed that the specific surface area increased as the P25 content increased, but this effect decreased as the ratio of T-sol to P25 increased. The thickness, surface roughness, transmittance, pencil hardness, and oil contact angle of the films were also affected by the P25 content, with increased thickness and surface roughness, decreased transmittance and pencil hardness, and decreased oil contact angle.