MOLECULES
·
2024
·Vol. 29
·期 16
·3843
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IF 4.2
Xinbao Li,Kai Sun,Ying Chen,Ye Yuan
As a widely used support, TiO2has often been combined with Pd to form highly sensitive gas-chromic materials. Herein, we prepared a series of Pd/TiO2catalysts with different Pd content (from 0.1 to 5 wt.%) by the impregnation method for their utilization in fast room-temperature CO detection. The detection was simply based on visible color change when the Pd/TiO2was exposed to CO. The sample with 1 wt.% Pd/TiO2presented an excellent CO gasochromic character, associated with a maximum chromatic aberration value of 90 before and after CO exposure. Systematic catalyst characterizations of XPS, FT-IR, CO-TPD, and N2adsorption–desorption and density functional theory calculations for the CO adsorption and charge transfer over the Pd and PdO surfaces were further carried out. It was found that the interaction between CO and the Pd surface was strong, associated with a large adsorption energy of −1.99 eV and charge transfer of 0.196e. The color change was caused by a reduction in Pd2+to metallic Pd0over the Pd/TiO2surface after CO exposure.
研究领域:
材料科学
·
化学
✓ 已验证
产品关联
DOI
PubMed
高影响因子
SENSORS AND ACTUATORS B-CHEMICAL
·
2025
·
IF 7.7
Rushun Xue,Lingmin Yu,Man Gong,Chuantao Zhang,Senlin Li,Shanglin Yang,Xuefeng Xiao,Ning Nan,Chun Li,Xinhui Fan
CuO is a typical p-type semiconductor with the advantage of narrow bandgap, making it a gas sensing material for detecting CO gas at lower operating temperatures.However, the poor response value limits its application. As a classical wide-band gap n-type gas sensing metal oxide semiconductor, TiO 2 has the advantages of high response to CO. However, high operating temperature becomes the big obstacle to overcome. Therefore, sensitive CO detection at lower temperature will be achieved by integration of CuO with TiO 2 . In this paper, in-situ two step hydrothermal method was used to prepare CuO/TiO 2 vertical bilayer nanorod arrays grown in situ. The gas sensing results show that the response value of the CuO/TiO 2 vertical bilayer nanorod arrays is 6.1 times (14.9, 300 ppm) higher than that of single CuO nanotentacle arrays (2.1, 300 ppm), and the operating temperature is reduced to 100 °C compared with pure TiO 2 nanorod arrays (360 °C). This strategy provides a new idea for the fabrication of CO gas sensors with high response and low operating temperature.
研究领域:
材料科学
·
化学
✓ 已验证
产品关联
DOI
高影响因子
SENSORS AND ACTUATORS B-CHEMICAL
·
2023
·
IF 8.4
Cong Qin,Zhanxiang Wei,Bing Wang,Yingde Wang
In the realm of gas sensors, p-type metal oxide semiconductor (MOS) usually exhibits inherently low sensitivity toward target gases caused by the hole accumulation layer configuration , which seriously hinders its practical application. Diatomics co-doping is an efficient tactic for adjusting the characteristics of MOS related to gas-sensing due to their synergistic effect . In this work, we controllably synthesized bare Co 3 O 4 , Sn-doped Co 3 O 4 , Mn-doped Co 3 O 4 and Sn/Mn co-doped Co 3 O 4 nanosheets . The experimental results reveal that Sn/Mn co-doped Co 3 O 4 sample presents porous nanosheets structure. 1 mol% Sn/Mn co-doped Co 3 O 4 sensor presents enhanced response [(R g -R a )/R a = 330 %∼40 ppm at 150 °C] toward CO compared with the bare Co 3 O 4 , 1 mol% Sn-doped Co 3 O 4 , and 1 mol% Mn-doped Co 3 O 4 nanosheets. Besides, 1 mol% Sn/Mn co-doped Co 3 O 4 nanosheets show a low limit of detection (500 ppb/experimental value), good stability and selectivity. We infer that the good CO-sensing properties may be ascribed to the oxygen vacancies defects generated by Sn 4+ and Mn 2+ /Mn 3+ co-doping, high Co 3+ ratio, and high specific surface area. This study affords an effective co-doping strategy for enhancing the gas-sensing performances of p-type MOS.
研究领域:
材料科学
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传感器技术
✓ 已验证
产品关联
DOI
高影响因子
CHEMICAL ENGINEERING JOURNAL
·
2025
·
IF 13.2
Zhicai Yu,Lele Huang,Mi Zhou,Jie Xu,Jianchao Ma,Yuhang Wan,Qing Jiang,Xueru Qu,Hualing He
Early fire warning represents an effective mean in the face of fire that can remind people in timely manner to adopt effective countermeasures before the occurrence of fire. Despite the encouraging progress of current early fire-warning sensors, a more sensitive monitoring of early fires in multiple aspects remains challenge. Herein, a dual-mode core-sheath structured SnO 2 /MoS 2 @MXene@ANFs (SMA) early fire warning sensor fiber was prepared by coaxial wet spinning technology. The core-layer of SMA fiber comprised the thermoelectric material Ti 3 C 2 T X MXene, whereas the shell-layer comprised the gas-sensitive SnO 2 /MoS 2 and silver nanowires (Ag NWs) along with aramid nanofibers (ANFs). The robust and flame-retardant ANFs served as protective shell, safeguarding the stability and flexibility of the temperature and gas sensing functions within the fiber. Based on the thermoelectric performance of MXene, there is a linear relationship between the output voltage and temperature difference of SMA fiber, which can achieve wide range of temperature sensing from 50 to 300 ℃ and accurately identify abnormal temperature increases in the environment. Simultaneously, The bridging effect between one-dimensional Ag NWs and SnO 2 /MoS 2 enhances the sensing capability of fiber for CO (R 0 /R = 1.43@100 ppm). In addition, an early fire warning system based on SMA fiber has been established, which can sensitively detect the flames (≤4 s). This system can also be used for monitoring CO gas in fire environments, guiding firefighters’ rescue actions, expanding the application scope of early fire warning sensors in the past, and opening up new directions for the development of intelligent early fire sensors in the future.
研究领域:
材料科学
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传感器技术
✓ 已验证
产品关联
DOI
高影响因子
RSC Advances
·
2019
·Vol. 9
·期 40
·22875-22882
·
IF 3.049
Pengjian Wang,Tingbiao Yuan,Huifang Yuan,Xiaoyan Zheng,Hamza Ijaz,Junfeng Hui,Daidi Fan,Yuxin Zhao,Shi Hu
In this paper, we developed a simple two-step route to prepare a PdO/SnO2 heterostructure with the diameter of the SnO2 and PdO nanoparticles at about 15 nm and 3 nm, respectively. In the evaluation temperature window between 80 °C and 340 °C, PdO/SnO2 shows the best response to 100 ppm of CO at 100 °C with fast response time (14 s) and recovery time (8 s). Furthermore, the PdO/SnO2 nanoparticles exhibit a low detection limit and good selectivity to CO against interfering gases as well as rarely-seen low-temperature stability and reversibility. Such enhanced gas sensing performance could be attributed to both the ultrafine structure of PdO and the synergy between PdO and SnO2. The results clearly indicate the application of PdO/SnO2 as a pratical low-temperature sensing material for CO.
研究领域:
材料科学
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传感器技术
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纳米技术
✓ 已验证
产品关联
DOI
PubMed
高影响因子
OPTICAL MATERIALS
·
2025
·
IF 4.2
Jingyan Yu,Rajendran Kalimuthu,Xingchen Liu,Wengao Zhang,Yonggen Tan,Kun Yan,Shenglin Ye,Jun Feng
Carbon quantum dots (CQDs) hold great potential as fluorescence probes due to their tunable optical properties, but remain challenges in tailoring surface functionalization for selective metal ion detection, which is essential for environmental monitoring and water quality analysis. This work, synthesized nitrogen and sulfur co-doped carbon quantum dots (N, S-CQDs) were via a one-pot solvothermal method with two different solvents, N, N-dimethylformamide (DMF) and acetone. The influences of solvent selectivity on the surface functionality of CQDs and their fluorescence quenching mechanisms were evaluated in both experimental and computational methods. To represent CQDs surfaces, density functional theory (DFT) calculations of the total density of states (TDOS) and partial density of states (PDOS) were conducted. Our findings revealed that synthesized CQDs in DMF and acetone exhibited fluorescence quenching as static and dynamic. We have achieved the highest quantum yields of 37.85 % and 28.59 %. This shows excellent sensitivities of Fe 3+ at 0.82 μM and 1.19 μM for Co 2+ . Furthermore, the study extended to validated in real water sample analysis. This approach enabled the development of a novel strategy for the selective and sensitive detection of Fe 3+ and Co 2+ ions.
研究领域:
环境科学
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材料科学
✓ 已验证
产品关联
DOI
高影响因子
SENSORS AND ACTUATORS B-CHEMICAL
·
2025
·
IF 7.7
Ziwen Yao,Jing Li,Shuai Nie,Yuan Wang,Xitao Yin,Yunxia He
Utilizing p-n composite materials for the fabrication of metal-oxide semiconductor (MOS) gas sensors represents a promising strategy to achieve exceptional selectivity in detecting reducing gases such as hydrogen (H₂) and carbon monoxide (CO). However, previous studies have typically achieved this selectivity under fixed operating temperatures and single molar ratios. This study presents the successful synthesis of n-In₂O₃/p-Co₃O₄ nanoparticles, featuring a p-n heterojunction structure, using a simple composite preparation method. The gas-sensing properties, crystal structure, morphology, and chemical states were comprehensively characterized using an electrochemical workstation, XRD, TEM, HRTEM, and XPS. Experimental results show that the gas sensor responses of the n-In₂O₃/p-xCo₃O₄ composites (with x = 10.5, 15, 18, 21), annealed at 500°C within an operational temperature range of 350°C to 400°C, exhibit distinct behaviors for CO and H₂ gases. This addresses the challenge of achieving selective detection across varying conditions. Notably, the n-In₂O₃/p-18Co₃O₄ composites display opposing response characteristics for both gases across a broad temperature range of 200°C to 400°C. At 350°C, the n-In₂O₃/p-18Co₃O₄ sensor demonstrates optimal selectivity, significantly minimizing cross-sensitivity and improving detection accuracy and reliability. The sensor also shows excellent stability, with consistent responses under repetitive exposure conditions. By improving both sensor selectivity and stability, this research advances gas detection technologies, with potential applications in sustainable energy and public health monitoring.
研究领域:
材料科学
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传感器技术
·
化学工程
✓ 已验证
产品关联
DOI
高影响因子
ACS Applied Nano Materials
·
2022
·
IF 6.14
Bingcai Chen,Pengpeng Li,Lian Sun,Yingde Wang,Bing Wang
To selectively detect trace carbon monoxide (CO typically lower than 100 ppb) at low temperature is still a great challenge for chemiresistive gas sensors. In this work, we introduce In2O3 nanocubes with exposed {001} facets to couple with MOF-derived porous Co3O4 nanosheets (NSs) forming p–n heterojunction for trace CO detection. Benefiting from the vacancy storing effect of the sub-valent band on In2O3 nanocube {001} facets and the p–n heterojunction effect, the electron–hole recombination is effectively inhibited, and the carrier lifetime is prolonged. As a result, the prepared CoIn0.1-based gas sensor shows a good selectivity and ultralow detection limitation of 25 ppb toward CO at relatively low temperature of 175 °C. In addition, the CoIn0.1-based CO sensor also exhibits high response (272.89%) and ultrafast response/recovery time (2 s/13 s) to 100 ppm CO, which can be ascribed to the fast gas diffusion in the porous Co3O4 NSs and the high-index facet effect of In2O3 nanocubes. This work provides a method to design and synthesize trace CO gas sensors via modulating the band structure of p–n heterojunctions constructed by two-dimensional metal oxide NSs and oxide-exposed high-index facets.
研究领域:
材料科学
·
纳米技术
·
气体传感
·
化学电阻传感器
✓ 已验证
产品关联
DOI
高影响因子
危险品化学品经营许可证（带存储）