RSC Advances
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2020
·Vol. 10
·期 5
·2472-2482
·
IF 3.119
Jie Meng,Fan Fang,Nengjie Feng,Hui Wan,Guofeng Guan
To improve the catalytic activity when utilizing metal oxides for the combustion of VOCs, Mn/Al-SBA-15 catalysts have been successfully synthesized through an emerging wetness impregnation technique involving Mn(NO3)2 on Al-SBA-15, which has been directly prepared from attapulgite by a hydrothermal method. Compared to Mn/SBA-15, which is prepared with TEOS as its silicon source, all the as-prepared Mn/Al-SBA-15 catalysts demonstrated enhanced catalytic performance in the oxidation of toluene. From this research, the 8% Mn/Al-SBA-15 catalyst presented the best catalytic performance, due to the high efficiency resulting from the high chemical valence of Mn4+. When the concentration of toluene was 2000 ppm, and the space velocity was 60 000 mL (g h)−1, 8% Mn/Al-SBA-15 could effectively reduce the T50 and T90 values of toluene to 201 and 278 °C, respectively; while the 8% Mn/SBA-15 catalyst could reduce the T50 and T90 values of toluene to 223 and 298 °C, respectively. A systematic investigation has been conducted to reveal the synergistic effects of Al doping and manganese loading on the enhanced catalytic performance. The experiments showed impressive results, demonstrating that Al doping can not only increase the surface acidity of SBA-15, but it can also be beneficial for achieving a uniform dispersion of MnOx on the surface and in the pores of Al-SBA-15, resulting in the enhancement of the catalytic performance.
研究领域:
环境科学
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催化
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化学工程
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材料科学
✓ 已验证
产品关联
DOI
PubMed
高影响因子
Nature Photonics
·
2024
·
IF 32.3
Ding Shuo,Wang Qiangqiang,Gu Wencui,Tang Zhaobing,Zhang Bo,Wu Chunyan,Zhang Xuanyu,Chen Hao,Zhang Xinyu,Cao Rui,Chen Tao,Qian Lei,Xiang Chaoyu
The efficiency and stability issues of perovskite light-emitting diodes, especially at high brightness, need to be urgently solved for displays and lighting applications. Herein we present a simple chemical washing method called solvent sieve to resolve the phase dimension issue of metal halide perovskites. After being sieved, undesirable defect-rich low- n phases are selectively screened out of perovskite multi-quantum-well structures. With better intrinsic structure refinement, the sieved perovskites demonstrated not only a record external quantum efficiency, current efficiency, and T 50 lifetime of 29.5%, 127.4 cd A −1 , and 18.67 h at 12,000 cd m − 2 (the equivalent of over 50,317 h or 5.7 years at 100 cd m − 2 ), respectively, with a maximum luminance of over 147,872.8 cd m − 2 , but also extraordinary resistance to air and moisture, maintaining over 75% of film photoluminescence quantum yield and 80% of device EQE after being stored at ambience for 100 days. The simple solvent sieve treatment we reported here confirms the feasibility of metal halide perovskites for luminescence and unleashes the efficiency and stability potentials of high-brightness perovskite light-emitting diodes for future commercial applications.
研究领域:
材料科学
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光电子学
·
化学
✓ 已验证
产品关联
DOI
高影响因子
ACS Applied Nano Materials
·
2024
·
IF 5.3
Li Luo,Zhen Fan,Zhaobin Zhang,Danyang Liu,Guofa Li,Lishuang Wang,Bingsuo Zou
SnO2 nanoparticles (NPs) have been used as an electron transport layer (ETL) in quantum dot light-emitting diodes (QLEDs) to achieve stable and high-performance devices. However, SnO2 NPs with high electron mobility cause the problem of imbalanced charge injection and transport in QLEDs. Meanwhile, the SnO2 NPs synthesized at low temperature have hydroxyl (−OH) groups, which could damage the performance of QLEDs. Here, Zn doping was applied to modulate the properties of SnO2 NPs and achieve better carrier balance in green CdSe/ZnS QLED. The maximum current efficiency (CE) of QLED with 5 wt % Zn-doped SnO2 NPs is 2.3-fold higher than that of SnO2-based QLED. In addition, a small-molecule 4,4′-bis(carbazole-9-yl)-1,1′-biphenyl (CBP)-mixed poly(9-vinylcarbazole) (PVK) layer was used as a hole transport layer to facilitate the hole injection and charge balance. As a result, a maximum external quantum efficiency (EQE) of 5.03% is obtained for the best performance device. The T50 lifetime at a luminance of 100 cd/m2, for a device based on 5 wt % Zn-doped SnO2 ETL, is 9141 h, which is 2.29-fold longer than the reference one. This work provides a new strategy to obtain high-performance and stable display arrays.
研究领域:
材料科学
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光电子学
·
纳米技术
✓ 已验证
产品关联
DOI
高影响因子
Molecular Catalysis
·
2024
·
IF 3.9
Xiaoying Zhou,Shiyu Fang,Zihao Hu,Zuliang Wu,Jing Li,Wei Wang,Jiali Zhu,Shuiliang Yao,Erhao Gao
This study introduces a novel catalyst system comprising Pd nanoparticles loaded onto Mn-doped NiO for the efficient oxidation of methane (CH 4 ) at low temperatures. The loading of Pd nanoparticles onto the Mn-doped support has yielded a catalyst with exceptional activity and stability, as evidenced by the lowest T 50 temperature of 276 °C and a CH 4 conversion reaching 97% at 325 °C. The catalyst demonstrates optimized reaction kinetics with the lowest activation energy of 69.2 kJ mol –1 . The catalyst's superior performance is attributed to the synergistic effects of the Pd/Mn-NiO composite, which include a higher Pd 2+ /Pd 4+ ratio, increased adsorptive oxygen concentration (O ads /O total ), and a reduced Ni 3+ /Ni 2+ ratio. These characteristics collectively enhance the catalytic activity for CH 4 oxidation. The Mars-van Krevelen mechanism underpins the oxidation process, with Pd 2+ identified as the principal active site for CH 4 adsorption and dissociation. Diffuse reflectance infrared Fourier transform spectroscopy coupled with mass spectrometry elucidates the pathway of surface reactive oxygen species in the formation of key intermediates, such as formates, and underscores the accelerated decomposition of carbonate facilitated by the Pd modification on the Mn-NiO surface. The findings signify a significant advancement in the development of catalysts for environmental and energy-related applications, particularly in the mitigation of CH 4 emissions.
研究领域:
催化
·
环境科学
·
能源
✓ 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）