JOURNAL OF MATERIALS SCIENCE-MATERIALS IN ELECTRONICS
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2025
·Vol. 36
·期 4
·1-13
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IF 2.8
Wang Hanxiao,Zhang Hong,Li Mei,Zhang You,Li Zhicheng,Leng Senlin
NTC thermistors have broad application prospects, and low-temperature sintering of NTC thermistors is of great significance in reducing sintering costs and is beneficial for preparing multi-layer structured components with lower cost internal electrode conductors. In this work, a low-melting point compound basing on Y 2 Ba 2 Cu 2 O 7 is selected as sintering agent for the preparation of Li-doped Ni–Zn–O (Ni 0.97- x Zn x Li 0.03 O 2 , x = 0.1, 0.3, 0.5, 0.7) ceramic thermistors. The sintering temperature can be reduced by more than 250 °C comparing with the one of the related ceramics without sintering aid (NiO ceramics was sintered at 1400 °C). The fabricated Li-doped Ni–Zn–O ceramics consist of single salt-rock NiO phase for x ≤ 0.3 and are composed of NiO-rich and ZnO-rich phases for x = 0.5 or 0.7. All ceramics show typical NTC characteristics with a wide-range adjustable material constant ( B values ranging from 756 to 4967 K). The Ni–Zn–O ceramics have high aging stability with the resistance shift rates induced at 125 °C lower than 1.89%. The microstructure, conduction modes and aging mechanism were investigated using the XRD, SEM, XPS, and electrochemistry impedance spectra.
研究领域:
材料科学
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电子工程
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DOI
高影响因子
ACS Applied Materials & Interfaces
·
2020
·
IF 8.758
Hairus Abdullah,Noto Susanto Gultom,Hardy Shuwanto,Worku Lakew Kebede,Dong-Hau Kuo
Zn(O,S) has been successfully doped with different amounts of Ho and characterized with X-ray diffraction (XRD), scanning electron microscopy (SEM), transmission electron microscopy (TEM), diffuse reflectance spectroscopy (DRS), X-ray photoelectron spectroscopy (XPS), electrochemical impedance spectroscopy (EIS), and transient photocurrent (TPC). The as-prepared Ho-doped Zn(O,S) catalysts with different Ho amounts are evaluated for hydrogen evolution reaction. The catalyst with the best performance in evolving hydrogen is further utilized to hydrogenate 4-nitrophenol (4-NP) to 4-aminophenol (4-AP). It is found that doping with Ho obviously enhanced charge transfer and photoresponse properties of the catalyst. Therefore, the modified Zn(O,S) can optimally evolve hydrogen by 18 624 μmol/g, which is 20% higher than that of pristine Zn(O,S). Subsequently, the in situ generated hydrogen ions on catalyst surfaces also play an important role as a hydrogen source to hydrogenate 4-NP to 4-AP without any reducing agents such as NaBH4, which is commonly used as a hydrogen source. As Ho is doped in the lattices of Zn(O,S), it acts not only to separate photocarriers and to enhance the charge transfer but also to shorten the diffusion time of nitrophenolate ions to catalyst surfaces for further photocatalytic hydrogenation reaction (PHR) process. A plausible PHR mechanism has been provided to elucidate the great performance of Ho-modified Zn(O,S) for photocatalytic hydrogenation.
研究领域:
化学
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材料科学
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DOI
PubMed
高影响因子
ACS Applied Materials & Interfaces
·
2020
·
IF 8.758
Hairus Abdullah,Yu-Rou Ko,Dong-Hau Kuo,Noto Susanto Gultom
La–Sn-codoped Zn(O,S) catalysts were synthesized with different amounts (0%, 2.5%, 5%, and 10%) of Sn and a constant amount (10%) of La to improve the photocatalytic hydrogenation reaction (PHR) of azobenzene to aniline. The as-prepared catalysts were carefully characterized and tested for a hydrogenation reaction. The incorporation of Sn significantly enhanced the PHR activities since the incorporated Sn in the Zn(O,S) lattices could increase the conductivity of the catalysts to improve the charge transfer during the catalytic reaction as indicated with EIS measurement. Further measurement with a photoresponse of La–Sn-codoped Zn(O,S) catalysts also exhibited relatively higher intensities as compared to those of La-doped Zn(O,S) and Sn-doped Zn(O,S) catalysts. On the basis of the measurement results of EIS and transient photo current, the La–Sn-codoped Zn(O,S) with the best properties was further utilized for PHR to convert azobenzene to aniline. GC–MS measurement confirmed that 15 ppm azobenzene could be totally converted to aniline in only 60 min which was achieved with a catalyst that was prepared with 5%-Sn and 10%-La doping. The relatively short reaction time indicated that the as-prepared catalyst had a strong reduction capability able to cleave the strong bonding of N═N in azobenzene. The reaction kinetic of the N═N bond cleavage was elucidated based on solvation, adsorption, pinning, and photocatalytic hydrogenation processes on the catalyst surfaces.
研究领域:
材料科学
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环境科学
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化学工程
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DOI
PubMed
高影响因子
JOURNAL OF INDUSTRIAL AND ENGINEERING CHEMISTRY
·
2019
·
IF 4.978
Fekadu Tadesse Bekena,Hairus Abdullah,Dong-Hau Kuo,Misganaw Alemu Zeleke
Novel Mg-doped Zn(O,S) nanoparticles were synthesized by a chemical precipitation process at 90 ℃ and the prepared nanoparticles were characterized by XRD, SEM, HRTEM, XPS, UV–vis, DRS, PL, EIS, and photocurrent response. The photocatalytic reduction for the 4-nitrophenol using Na 2 SO 3 under UV light irradiation showed that Mg–Zn(O,S)-2.5 exhibited higher activity compared with other samples. 96.7% of 4-nitrophenolate ion reduced into 4-aminophenol within 45 min. Mg–Zn(O,S)-2.5 was also tested for hydrogen evolution, where the rates of 1035 μmol/g for the 4-NP-free sample and 705 μmol/g for the 4-NP-added one were achieved. Finally, the stability and reaction mechanism was mentioned.
研究领域:
材料科学
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环境科学
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化学工程
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DOI
高影响因子
ACS Applied Materials & Interfaces
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2021
·
IF 9.229
Wenwei Lin,Wen-Ti Guo,Liquan Yao,Jianmin Li,Limei Lin,Jian-Min Zhang,Shuiyuan Chen,Guilin Chen
Hydrothermal deposition is emerging as a highly potential route for antimony-based solar cells, in which the Sb2(S,Se)3 is typically in situ grown on a common toxic CdS buffer layer. The narrow band gap of CdS causes a considerable absorption in the short-wavelength region and then lowers the current density of the device. Herein, TiO2 is first evaluated as an alternative Cd-free buffer layer for hydrothermally derived Sb2S3 solar cells. But it suffers from a severely inhomogeneous Sb2S3 coverage, which is effectively eliminated by inserting a Zn(O,S) layer. The surface atom of sulfur in Zn(O,S) uniquely provides a chemical bridge to enable the quasi-epitaxial deposition of Sb2S3 thin film, confirming by both morphology and binding energy analysis using DFT. Then the results of the first-principles calculations also show that Zn(O,S)/Sb2S3 has a more stable structure than TiO2/Sb2S3. The resultant perfect Zn(O,S)/Sb2S3 junction, with a suitable band alignment and excellent interface contact, delivers a remarkably enhanced JSC and VOC for Sb2S3 solar cells. The device efficiency with the TiO2/Zn(O,S) buffer layer boosts from 0.54% to 3.70% compared with the counterpart of TiO2, which has a champion efficiency of Cd-free Sb2S3 solar cells with a structure of ITO/TiO2/Zn(O,S)/Sb2S3/Carbon/Ag by in situ hydrothermal deposition. This work provides a guideline for the hydrothermal deposition of antimony-based films upon a nontoxic buffer layer.
研究领域:
材料科学
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太阳能
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半导体物理
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DOI
PubMed
高影响因子
Catalysis Science & Technology
·
2019
·Vol. 9
·期 10
·2651-2663
·
IF 5.726
Hairus Abdullah,Dong-Hau Kuo,Noto Susanto Gultom
Hydrogen-evolved Dy-doped Zn(O,S) photocatalysts with different amounts of Dy precursor have been synthesized, characterized and further utilized for hydrogenation reactions. The Dy catalysts are first examined using electrochemical impedance spectroscopy, photo responsivity, and the hydrogen evolution reaction. Dy-doped Zn(O,S) with 10% Dy precursor shows the best photocatalyst performance with the highest H2 production rate of 8.160 mmol g−1 h−1. This catalyst is chosen for conducting the hydrogenation reaction. It is our intention to confirm the correlation between the photocatalytic H2 production rate and the hydrogenation reactions of 4-nitrophenol to 4-aminophenol and azobenzene to aniline, which is a step further in the hydrogenation reaction to challenge the NN bond cleavage of azobenzene. A 100% photo conversion of 60 ppm azobenzene to aniline in 6 h was confirmed under a low-power UV light illumination in a 10% ethanol solution. Kinetic steps and kinetic mechanisms are proposed, which involve the important reaction steps of solvation, adsorption, pinning, and surface hydrogenation reaction operating together.
研究领域:
化学
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材料科学
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DOI
高影响因子
COLLOIDS AND SURFACES A-PHYSICOCHEMICAL AND ENGINEERING ASPECTS
·
2024
·
IF 4.9
Worku Lakew Kebede,Dong-Hau Kuo,Xiaoyun Chen
Environment and energy are presently some of the highest priority topics for mankind that need to be addressed. Organic pollutants are toxic and carcinogenic for human and aquatic life hence their presence in water even in low concentrations can cause serious health problems. Photodegradation of organic pollutants by utilizing oxide-based heterostructure photocatalysts is the promising approach to carry out remediation efficiently ascribed to the advanced optoelectronic and structural superiority of oxide photocatalysts. The Zn(O,S)/Mo(O,S) 2 composites were synthesized via a facile solvothermal method at low temperatures. Several methods were used to characterize the composite morphology, structure, electrical conductivity, chemical composition, and optical characteristics. The heterostructured Zn(O,S)/Mo(O,S) 2 oxysulfide was employed successfully in the photocatalytic degradation of organic pollutants. Among the as-prepared samples, the 30-ZnMoOS composite catalyst was found to have the highest photodegradation performance on various organic dye pollutants. The photocatalytic activity of the as-synthesized Zn(O,S)/Mo(O,S) 2 samples was assessed on the photodegradation of different kinds of organic dyes under visible light irradiation. The photocatalytic degradation efficiency of 30-ZnMoOS composite over 10 ppm neutral red (NR), methylene blue (MB), rhodamine B (Rh B), and methyl orange (MO) was found to be 99.6 %, 99.9 %, 99.5 %, and 98.8 % within 40, 45, 180, and 180 min, respectively, under visible light illumination. In the present photocatalytic system, the superoxide ( . O 2 - ) anions, hydroxyl ( . OH) radicals, and holes (h + ) are proposed to be the direct reactive species causing the photodegradation of organic dyes.
研究领域:
环境科学
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材料科学
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DOI
高影响因子
Catalysis Science & Technology
·
2021
·Vol. 11
·期 21
·7200-7216
·
IF 6.119
Hairus Abdullah,Hardy Shuwanto,Dong-Hau Kuo
A Ni–Mg bimetal-doped Zn(O,S) photocatalyst has been synthesized, characterized, and tested for several photocatalytic applications. The hydrogen generation reaction, hydrogenation reaction for chemical transformation, detoxification of hexavalent chromium, and mixed dye (MB + RhB + MO) degradation under simulated solar-light illumination were confirmed. The essential characterization results indicated improved oxygen vacancy sites on the catalyst with enhanced photoresponse, better photocarrier separation, and facile charge transfer properties. A typical catalyst, NMZ-S10, was evaluated with a 1000-cycle CV test to demonstrate its long-term use for industrial application. Stable reusability experiments for the HER, PHR, PHC reaction, and PDM also supported the long-term application. The photocatalytic HER of NMZ-S10 could evolve hydrogen at a rate of 4000 μmol g−1 h−1. 30 ppm azobenzene-to-aniline conversion was completely done in 2 h of reaction. Detoxification of 30 ppm hexavalent chromium was conducted in 70 min of reaction. Finally, 10.5 ppm MB–RhB–MO mixed dye degradation was carried out in 1 h of reaction. The as-synthesized NMZ-S10 catalyst has demonstrated its capability to overcome energy and environmental issues promisingly. The great photocatalytic activities are discussed and elucidated with a plausible mechanism to rationalize the superb catalytic performance.
研究领域:
材料科学
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环境科学
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DOI
高影响因子
ADVANCED POWDER TECHNOLOGY
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2019
·
IF 3.25
Kedir Ebrahim Ahmed,Dong-Hau Kuo,Worku Lakew Kebede
Heterojunction construction with low band gap materials is an effective way of utilizing UV light active materials under visible light irradiation. Here, we report the synthesis of Bi 2 (O,S) 3 /Zn(O,S) heterostructure using simple solvothermal method without surfactant. The catalysts were investigated with different characterization techniques. All the composite catalysts showed high light absorption capacity in the whole visible light spectrum. The catalytic activity of the catalysts was evaluated by Cr(VI) reduction. While pure Zn(O,S) catalyst showed no significant Cr(VI) reduction, higher photocatalytic activity than individual components were exhibited after heterojunction construction with Bi 2 (O,S) 3 . 20-BiZnOS catalyst with Bi/Zn molar percentage of 20% showed the best photocatalytic activity among the composites with 99.5% Cr(VI) reduction within 12 min under visible light irradiation. Heterojunction formation between Bi 2 (O,S) 3 and Zn(O,S) nanoparticle, and selective adsorption of Cr(VI) and desorption of Cr(III) on the surface of 20-BiZnOS composite catalyst were ascribed to the enhanced photocatalytic activity of the composite catalyst.
研究领域:
环境科学
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材料科学
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化学工程
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DOI
高影响因子
JOURNAL OF THE AMERICAN CERAMIC SOCIETY
·
2025
·
IF 3.8
Shuangjiang He,Junchang Wang,Chong Wang,Xiao Zhang,Sen Liang
The Mn-Fe-Co-Zn-O series is a widely used thermistor material, but its thermal stability is compromised by nitrogen glass encapsulation, limiting its application in electrical devices. To address this issue, La 2 O 3 and Y 2 O 3 were used as rare earth oxide dopants, and xR 2 O 3 -Mn 0.76 Fe 0.87 Co 1.07 Zn 0.3 O 4 (x = 0.0025, 0.005, 0.01, 0.02) negative temperature coefficient (NTC) materials were synthesized via solid-state sintering. The effect of rare earth doping on the electrical properties after high-temperature nitrogen annealing was investigated. After annealing at 750°C for 4 h, the variation in resistivity ( ρ 25 ) and material constant ( B 25/50 ) significantly decreases with increasing La doping. For the La-doped sample (x = 0.01), Δρ 25 decreased to 7.77% and ΔB 25/50 to 0.77% (for the Y-doped sample (x = 0.01), Δρ 25 decreased to 22.76% and ΔB 25/50 to 1.91%), compared to the undoped sample, where Δρ 25 reduced by 168.84% and ΔB 25/5 0 by 5.57%. This improvement was attributed to rare earth accumulation at grain boundaries, filling voids and forming R-O bonds, which inhibited oxygen vacancy migration and significantly reduced grain boundary resistance. Rare earth doping effectively improved the thermal stability and electrical consistency of NTC thermistor ceramics in high-temperature nitrogen atmospheres, offering a new strategy for high-temperature encapsulation applications. (Y-doped samples showed similar results, as detailed in the Supplementary Materials.)
研究领域:
材料科学
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无机非金属材料
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电子陶瓷
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热敏材料
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固态化学
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DOI
高影响因子
CHINESE JOURNAL OF CATALYSIS
·
2025
·
IF 17.7
Pengkun Zhang,Qinhan Wu,Haoyu Wang,Dong-Hau Kuo,Yujie Lai,Dongfang Lu,Jiqing Li,Jinguo Lin,Zhanhui Yuan,Xiaoyun Chen
Herein, we established a Zn 3 (OH) 2 (V 2 O 7 )(H 2 O) 2 /V-Zn(O,S) Z-scheme heterojunction (labeled ZnVO/V-Zn(O,S) with a heterovalent V 4+ /V 5+ states and oxygen vacancies in both phases via a one-step in-situ hydrolysis method. The NaBH 4 regulated the ZnVO/V-Zn(O,S)-3 with rich Vo and suitable n (V 4+ )/ n (V 5+ ) ratio achieved an excellent photocatalytic nitrogen fixation activity of 301.7 μmol/(g·h) and apparent quantum efficiency of 1.148% at 420 nm without any sacrificial agent, which is 11 times than that of V-Zn(O,S). The Vo acts as the active site to trap and activate N 2 molecules and to trap and activate H 2 O to produce the H for N 2 molecules photocatalytic reduction. The rich Vo defects can also reduce the competitive adsorption of H 2 O and N 2 molecules on the surface active site of the catalyst. The heterovalent vanadium states act as the photogenerated electrons, quickly hopping between V 4+ and V 5+ to transfer for the photocatalytic N 2 reduction reaction. Additionally, the Z-scheme heterojunction effectively minimizes photogenerated carrier recombination. These synergistic effects collectively boost the photocatalytic nitrogen fixation activity. This study provides a practical method for designing Z-scheme heterojunctions for efficient photocatalytic N 2 fixation under mild conditions.
研究领域:
材料科学
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催化
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环境科学
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纳米技术
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化学工程
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产品关联
DOI
高影响因子
Materials Today Energy
·
2025
·
IF 8.6
Binghong Wu,Xinru Wu,Dong-Hau Kuo,Xiao Tang,Xin Mao,Baoqian Yang,Zhengjie Su,Pengkun Zhang,Longyan Chen,Minhao Liu,Jinguo Lin,Xiaoyun Chen
To reveal the role of bi-vacancy defects and heterovalent states in oxysulfide catalysts for enhancing the photocatalytic hydrogen evolution reaction (PHER), we demonstrate a Br/W co-doped Zn(O,S) catalyst (labeled as Br/W-ZnOS) featuring abundant anionic oxygen vacancies (V O )/cationic zinc vacancies (V Zn ) bi-defects and heterovalent W 5+ /W 6+ states via a facile hydrolysis method. The co-doping of Br and W induces lattice distortions that enable neighboring atoms to leave the lattice, creating surfaces enriched with anionic V O and cationic V Zn defects. The synergistic effect between dual defects forms an efficient electron-hole separation system, enhancing the efficiency of electron-hole pair separation. Density functional theory calculation (DFT) demonstrates that the combination of Br/W co-doping and vacancies significantly reduces the water dissociation barrier and optimizes the surface ∗H generation rate of the photocatalyst. Thus, Br/W-ZnOS exhibits a PHER rate of 3415.7 μmol h −1 , which is 12.5 times higher than the undoped Zn(O,S) catalyst, and achieves an apparent quantum yield (AQY) of 15.41 % at 365 nm, while maintaining good stability with a PHER activity of 3288.1 μmol h −1 after five repeated cycles. This research provides a promising strategy for designing oxysulfide catalysts with synergistically engineered defects for efficient PHER.
研究领域:
材料科学
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催化化学
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理论计算化学
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DOI
高影响因子
危险品化学品经营许可证（带存储）