Molecular Catalysis
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2021
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IF 5.062
Junyi Liu,Xianxiang Liu,Qiong Xu,Dulin Yin
A series of highly active and ortho -position selective catalysts based on (α-Fe 2 O 3 ) 1- x (V 2 O 5 ) x catalysts were proposed for the C -methylation of phenol with methanol. The (α-Fe 2 O 3 ) 1- x (V 2 O 5 ) x catalysts were synthesized by coprecipitation method of Fe and V elements and microwave drying. The chemical composition, material structure, acid-base properties, and structure-activity relationship of (α-Fe 2 O 3 ) 1- x (V 2 O 5 ) x catalysts were systematically analyzed by the techniques of XRD, XPS, TEM, N 2 adsorption-desorption, Raman, UV-Vis, ESR, NH 3 /CO 2 -TPD and Pyridine-IR. The (α-Fe 2 O 3 ) 1- x (V 2 O 5 ) x catalysts have the double advantages of high activity and high stability for the methylation of phenol due to the high BET surface area, large total pore volume, dispersive active sites and enhanced acid-base property. o -cresol and 2,6-xylenol were the main products, and nearly 100% selectivity to the ortho -position of phenol and 90% selectivity to o -cresol were obtained. Furthermore, the (α-Fe 2 O 3 ) 1- x (V 2 O 5 ) x catalysts possess long lifetime over 2500 h and high activity at a weight hourly space velocity of 1.6 h −1 compared with the microwave-dried α-Fe 2 O 3 catalyst. The doping of vanadium improves the activity and stability of α-Fe 2 O 3 catalyst, which attributes to the modification of catalyst structure, especially the improvement of acid-base centers and oxygen vacancy. Recently the (α-Fe 2 O 3 ) 1- x (V 2 O 5 ) x catalysts have been stably and efficiently applied in industry for the methylation of phenol.
研究领域:
催化化学
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材料科学
✓ 已验证
产品关联
DOI
高影响因子
Advanced Energy Materials
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2025
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IF 26
Shengxiang Kang,Jiyao Zhang,Haojie Liang,Jiaming Huang,Zhiwei Ren,Teng He,Xiaohui Liu,Jing Zhang,Yuejin Zhu,Kuan Liu,Gang Li,Like Huang
Perovskite solar cells (PSCs) face challenges in long-term stability, especially under reverse bias. Here, a water-soluble vanadium pentoxide (V 2 O 5-x ) hole-collecting layer (HCL) is introduced into inverted PSCs to improve the photovoltaic performance and multiple-scenario stability under operational, thermal recycle, and reverse bias. V 2 O 5-x annealed at 50–250°C are characterized for multiple physical properties, revealing that 150°C annealing optimizes oxygen vacancy to reduce trap density and improve interface carrier collection. The champion device based on (FA 0.83 MA 0.17 ) 0.95 Cs 0.05 Pb(I 0.95 Br 0.05 ) 3 absorber achieves power conversion efficiency (PCE) of 23.3% with negligible hysteresis (HI = 0.64%) and good stability (retains ∼88% of initial PCE after 1000 h of storage). Further, with Cs 0.05 MA 0.1 FA 0.85 PbI 3 as absorber, the PCE of the device can be further improved to be 25.88% with an HI of 3.26%, superior to the device without V 2 O 5-x (PCE = 24.94%, HI = 5.47%). Moreover, the operational and thermal cycling stability of the device has been obviously improved. Crucially, V 2 O 5-x enhances the reverse breakdown voltage from about |−2| to |−6| V, endowing the device with higher reverse bias stability and tolerance to the shadow effect. These results demonstrate that V 2 O 5-x can simultaneously boost PCE and stability of PSCs, offering a promising route toward efficient and durable PSCs.
研究领域:
光伏技术
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材料科学
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能源材料
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半导体器件
✓ 已验证
产品关联
DOI
高影响因子
CHEMICAL ENGINEERING JOURNAL
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2025
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IF 13.2
Junde Zhang,Yanmei Cheng,Chunhui Du,Guangming Nie
Electrochromic supercapacitors (EC-SC), which integrate energy storage and intelligent light modulation, show broad application prospects despite being constrained by limitations such as single-color variation, sluggish color transition kinetics, and inadequate electrical conductivity. To break through this bottleneck, we simultaneously introduce Co single-atoms and oxygen vacancies (Ov) into the V 2 O 5 substrate and further modify it with poly(5-formylindole) (P5FIn), thereby greatly improving the conducting and electrochromic performance of the material. The modified P5FIn/Co-V 2 O 5-x electrochromic film has a capacitance of 291.6 mF cm −2 at a current density of 1 mA cm −2 and an optical modulation effect of 54.5 % at 800 nm, while its capacitance remains at 95 % during 10,000 charge and discharge tests. The finely tuned EC-SC has high specific capacitance (241.1 mF cm −2 ), practical power density and capacity density (1.7 W cm −2 and 133.94 mWh cm −2 ), significant optical contrast (ΔT 980 nm = 71 %), high coloration efficiency (156.4 cm 2 C −1 ), fast switching (4.2 s/4.2 s for color rendering/bleaching), and long operational stability (>3000 cycles). In this study, a synergistic structure that combines Ov, single-atoms, and conductive polymers is constructed, which leads to significant enhancements in optical response, capacitive performance, and cycling stability, and this work presents a scalable strategy for designing high-performance EC-SC devices.
研究领域:
材料科学
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电化学
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纳米技术
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能量存储
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智能材料
✓ 已验证
产品关联
DOI
高影响因子
ACS Applied Energy Materials
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2025
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IF 5.5
Shengxiang Kang,Yaxuan Liu,Haojie Liang,Min Wang,Xiaohui Liu,Jing Zhang,Kuan Liu,Yuejin Zhu,Like Huang
Recently, with the advantage of a multivalent state, facile, and low-temperature preparation method, vanadium oxide (V2O5-x) has emerged as a potential anode buffer layer for perovskite solar cells (PSCs). Almost all works claim that the prepared V2O5-x is a p-type semiconductor and, therefore, serves as a hole transport layer. In this work, we demonstrate water-soluble V2O5-x exhibiting n-type conductivity, which can still serve as an effective hole collection layer (HCL) in PSCs. Comprehensive characterizations and DFT calculations reveal that V2O5-x is an n-type semiconductor with a high work function (WF). Further coupled with self-assembled monolayer, it can simultaneously optimize the front interface band bending via enhancing the ITO electrode’s WF and reduce interface defect density, thereby facilitating carrier collection and suppressing nonradiative recombination, leading to an inverted PSC with a highest power conversion efficiency of 23.5% and underscoring the importance of strategic interface engineering rather than only relying on a conventional p-type conduction paradigm. Moreover, the device exhibits excellent reverse bias stability. The high-WF n-type V2O5-x HCL pushes the device’s reverse breakdown voltage to reaching |−31.77| V, far beyond that of the conventional NiOx-based device (about |−6| V). This work highlights facile water-soluble V2O5-x-based PSCs that demonstrate a device operating mechanism and high reverse bias stability, which provides a feasible route to achieving efficient and stable PSCs.
✓ 已验证
产品关联
DOI
高影响因子
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