EUROPEAN POLYMER JOURNAL
·
2020
·
IF 3.862
Yuejia Zhu,Yongzhu Hu,Zhenjiang Li,Bo Liu,Yuanyuan Qu,Zhihao Zhang,Tianfo Guo,Yongqiang Li,Luoyu Gao,Kai Guo
Hydrogen bond donor (HBD) and organic base binary cocatalyst established a gold standard in organocatalytic ring-opening polymerizations (ROPs). In depth probe of the mechanisms revealed that proton abstraction of the acidic H on the HBDs by the bases do occur frequently. A truly simple HBD and Lewis base (LB) cocatalysis, however, was elusive. We proposed genuine HBD/LB cocatalyst for ROPs by introducing 3-amino-1,2,4-benzothiadiazine-1,1-dioxide (ABTD) as a bidentate H-bond donor and triethylamine (TEA) as a mild Lewis base. ROPs of lactide (LA) and trimethylene carbonate (TMC) in solutions at room temperature were success. The mild ROPs produced polylactide (PLA) of predictable molecular weights (from 1.6 to 26.7 kg mol −1 ) and extremely narrow dispersities (Đ 1.01 to 1.06). Furthermore, well-defined diblock copolymers PTMC-b-PLA were synthesized. NMR titration experiments verified exclusive H-bond donor activation of the monomer and TEA activation of the hydroxyl chain end without trace of proton abstraction.
研究领域:
化学
·
材料科学
✓ 已验证
DOI
高影响因子
ACS Applied Materials & Interfaces
·
2023
·
IF 9.5
Yuyu Liu,Minming Yan,Jia Shu,Hongwei He,Zi Wang,Ziyu Qin,Yunwei Wang,Yong Zhang
The distinctive characteristics of blue quantum dots (QDs) such as their deep valence band and large bandgap give rise to an elevated hole injection barrier between the hole transport layers (HTLs) and the QD active layer. This results in an imbalance of carrier transport and injection across the device, leading to a degrading performance in QD light-emitting diodes (QLEDs). In this paper, high-efficiency and low-efficiency degradation blue CdSe/CdS/ZnS QLEDs were fabricated by using the Lewis base, 1,2-bis(diphenylphosphino)ethane (DPPE), blended with poly(9-vinylcarbazole) (PVK) (DPPE:PVK) as HTLs. The device performance of blue QLEDs can be finely adjusted by manipulating the blending ratio between DPPE and PVK. When 4 wt % DPPE was blended with PVK (4 wt % DPPE:PVK) as the HTL, the device achieved its optimal performance. Compared to the device with neat PVK as the HTL, the turn-on voltage of blue QLEDs with the 4 wt % DPPE:PVK HTL is reduced from 3.21 to 2.9 V. The maximum current efficiency (CE) and external quantum efficiency (EQE) of blue QLEDs increase from 2.92 cd A–1 and 5.89% in neat PVK to 5.75 cd A–1 and 11.75% for the 4 wt % DPPE:PVK HTL. Furthermore, the QLEDs incorporating DPPE:PVK HTLs exhibited exceptional resistance to efficiency degradation (EQE = 8.83%@L = 12,000 cd m–2 for 4 wt % DPPE:PVK as the HTL and EQE = 2.80%@L = 12,000 cd m–2 for neat PVK as the HTL). A more in-depth analysis reveals that enhanced device performance results from the chelating and bridging effect of the bidentate ligand Lewis base DPPE. These effects strengthen the binding of free metal ions in the blue QDs, reduce the charge barriers, enhance the contact between the HTLs and the QD active layer, and ultimately improve hole injection.
研究领域:
材料科学
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光电技术
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化学工程
✓ 已验证
产品关联
DOI
PubMed
高影响因子
APPLIED CATALYSIS B-ENVIRONMENTAL
·
2025
·
IF 21.1
Chunyu Zhang,Guang Yang,Xueqing Gao,Zhiyun Li,Yifan Li,Siyuan Wang,Junyong Wang,Xunhua Zhao,Kai Zhang,Yu Kang,Yi Cui
Surface OH species on electrocatalysts play a pivotal role in affecting the hydrogen evolution reaction (HER). Herein, we highlight the critical role of surface OH basicity in regulating interfacial water structure and OH desorption behavior. By annealing Ru/Ni(OH) 2 at various temperatures, we successfully tailored the electronic state of surface OH species, with the catalyst annealed at 300 °C (Ru-Ni-300) exhibiting superior HER performance, achieving a current density of 100 mA/cm 2 at an exceptionally low overpotential of 71 mV. X-ray photoelectron spectroscopy demonstrates that the electron-rich surface OH species on Ru-Ni-300 exhibit strong Lewis basicity. The enhanced OH basicity facilitates the formation of hydrogen-bond networks with interfacial water through electron donation, which in turn promotes OH desorption kinetics. Quasi-in-situ XPS and density functional theory calculations further elucidated that the increased electron density on surface OH species reduces OH adsorption energy, thus accelerating HER performance. These findings unveil a direct correlation between surface OH basicity and HER efficiency, offering new insights into tailoring surface environments for advanced water-splitting electrocatalysts.
研究领域:
电化学
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材料科学
✓ 已验证
DOI
高影响因子
JOURNAL OF ALLOYS AND COMPOUNDS
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2025
·
IF 6.3
Jiangning Li,Gangyi Zeng,Guangyao Liu,Weijian Yuan,Lingling Wen,Tiantian Wang,Xuelin Zhang,Xin Li
Lewis base molecules as common additives provide a promising strategy for regulating the nucleation and growth of high-performance perovskite solar cells (PSCs). However, the more complex nucleation pathways encountered by all-air-processed PSCs present more formidable challenges. Herein, we propose a post-adding strategy that incorporated the weakly alkaline molecule additive diazine into the perovskite precursor only introducing diazine prior to the spin-coating step to delay Lewis adduct generation and slow down the crystallization rate of perovskite in ambient air. Specifically, the diazine contained electron-rich N atoms not only can suppress the charged defects of perovskite films, but also improve the energy level alignment between the light absorption layer and the transport layers. By optimizing the concentration of diazine, the resulting PSCs fabricated in air without control atmosphere achieve a champion PCE of over 21 % and a high V OC of 1.2 V. Furthermore, the unencapsulated devices maintain over 80 % of their initial PCE after 1920h in the full ambient air condition (25 ± 5 % RH). This post-adding strategy of diazine provides a new view for finding suitable Lewis base additives and optimizing the fabrication conditions to realize efficient and stable all-air-processed PSCs.
研究领域:
材料科学
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能源技术
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化学工程
✓ 已验证
产品关联
DOI
高影响因子
Advanced Science
·
2022
·Vol. 9
·期 11
·2105556
·
IF 17.521
Bin Li,Feng-Fan Lu,Xiao-Wen Gu,Kai Shao,Enyu Wu,Guodong Qian
Developing efficient and stable water adsorbents for adsorption-driven heat transfer technology still remains a challenge due to the lack of efficient strategies to enhance low-pressure water uptakes. The authors herein demonstrate that the immobilization of Lewis basic nitrogen sites into metal–organic frameworks (MOFs) can improve water uptake and target benchmark coefficient of performances (COPs) for cooling and heating. They present the water sorption properties of a chemically stable MOF (termed as Zr-adip), designed by incorporating hydrophilic nitrogen sites into the adsorbent MIP-200. Zr-adip exhibits S-shaped sorption isotherms with an extremely high water uptake of 0.43 g g −1 at 303 K and P / P 0 = 0.25, higher than MIP-200 (0.39 g g −1 ), KMF-1 (0.39 g g −1 ) and MOF-303 (0.38 g g −1 ). Theoretical calculations reveal that the incorporated N sites can serve as secondary adsorption sites to moderately interact with water, providing more binding sites to strengthen the water binding affinity. Zr-adip achieves exceptionally high COPs of 0.79 (cooling) and 1.75 (heating) with a low driving temperature of 70 °C, outperforming MIP-200 (0.78 and 1.53) and KMF-1 (0.75 and 1.74). Combined with its ultrahigh stability, excellent cycling performance, and easy regeneration, Zr-adip represents one of the best water adsorbents for adsorption-driven cooling and heating.
研究领域:
材料科学
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能源技术
✓ 已验证
产品关联
DOI
PubMed
高影响因子
JOURNAL OF COLLOID AND INTERFACE SCIENCE
·
2023
·
IF 9.9
Guodong Zhao,Ya Liu,Jingyu Pan,Chang Liu,Yinghe Hu,Zhe Gao,Xupin Zhuang
Excessive CO 2 emissions and the resultant global warming present significant environmental challenges, posing threats to human health and public safety. Metal–organic frameworks (MOFs), known for their high specific area and large porosity, hold the promise for CO 2 capture. However, a major obstacle is the low loading mass of MOFs and the limited interface affinity and compatibility between MOFs and substrates. In this study, we present an electrospinning-assisted in-situ synthesis dual metallic framework strategy for preparing flexible Zn/Co-ZIF nanofibrous membranes (NFMs). This method achieves the high loading mass of MOFs and introduces abundant Lewis basic sites, thereby enhancing the CO 2 adsorption. The dual metallic Zn/Co-ZIF NFMs exhibit remarkable features, including high MOF loading mass (70.23 wt%), high specific surface area (379.63 m 2 g −1 ), large porosity (92.34 %), high CO 2 adsorption capacity (4.43 mmol/g), high CO 2 /N 2 adsorption selectivity (37), and high CO 2 /CH 4 adsorption selectivity (31). Moreover, the dual metallic Zn/Co-ZIF NFMs demonstrate robust structural stability and durability attributed to the excellent interface affinity between MOFs and NFMs, retaining 96.56 % of their initial capacity after 10 adsorption–desorption cycles. This work presents a prospective direction for developing flexible dual metallic MOF NFMs for the efficient capture of CO 2 .
研究领域:
材料科学
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环境科学
✓ 已验证
产品关联
DOI
PubMed
高影响因子
CHEMISTRY-A EUROPEAN JOURNAL
·
2024
·
IF 3.9
Fan Zhang,Yuanming Li,Xi Zhou,Qiang Zhao,Xuelian Li,Feng-Lian Zhang,Yi-Feng Wang,Xiaoguo Zhou
Graphical The reaction rate constants of a Lewis base-boryl radical, 4-dimethylaminopyridine (DMAP)-BH 2 •, with several methyl chlorobenzoates and chlorinated acetanilides are measured. Compared with the abstraction of the chlorine atom, the radical-addition to the carbonyl oxygen atom is more favorable as the rate-determining step in the whole reaction. The advanced strategy using Lewis base-boryl radicals (LBRs ) has recently been proposed for the addition of alkyl substituents to the full-carbon quaternary center of an organic molecule. However, as the rate-determining step in the whole route, reaction rate constants of LBRs with substrates are extremely lacking. In this paper, 4-dimethylaminopyridine (DMAP)-BH 2 ⋅ was selected as a representative of LBRs, and its reactions with six monochloro-substituted substrates, including three methyl chlorobenzoates and three chlorinated acetanilides were studied in experiments and theoretical calculations. The bimolecular reaction rate constants, k q , were determined using laser flash photolysis approach. By comparing activation energies along the two addition pathways, we have clarified the rate-determining step as the attacking to carbonyl oxygen instead of chlorine atom. Furthermore, noncovalent interaction (NCI) analyses on these substrates indicate that weak interactions, such as hydrogen-bonding and van der Waals interactions, have significant influence on the reactivity of these substrates. Our study provides concrete clues to extend this synthetic strategy.
研究领域:
有机化学
·
物理化学
✓ 已验证
DOI
PubMed
高影响因子
Nanoscale Advances
·
2020
·Vol. 2
·期 11
·5396-5402
·
IF 0
Zhou Liu,Shuzhen Wu,Xiaojie Yang,Yijun Zhou,Jiaren Jin,Junmei Sun,Li Zhao,Shimin Wang
Carrier recombination and charge loss at the interfaces of perovskite layers have a significant influence on high-performance planar perovskite solar cells (PSCs). We employed two-dimensional graphitic carbon nitride (g-C3N4), which is a heat-resistant n-type semiconductor, to modify the electron-transport layer/perovskite and perovskite/hole-transport layer interfaces, respectively. g-C3N4 could passivate the surface trap states of the methylammonium lead iodide light absorber through the formation of a Lewis adduct between N and the under-coordinated Pb, and it could also remarkably reduce the grain boundaries between perovskite crystal particles. A maximum power conversion efficiency (PCE) of 19.67% (Voc = 1.14 V, Jsc = 21.45 mA cm−2, FF = 0.807) could be obtained from planar PSCs with long-term stability using dual-positioned g-C3N4. Therefore, we consider that ultrathin semiconductor films with a Lewis base nature are suitable as dual-functional transport materials for devices. This work provides new guidance for dual-interfacial modification to improve the PCE and stability of devices.
研究领域:
材料科学
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新能源
·
半导体器件
·
界面工程
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光电子学
✓ 已验证
DOI
Advanced Energy Materials
·
2024
·Vol. 14
·期 26
·2401114
·
IF 24.4
Qin Li,Junjie Ma,Xuanchen Xu,Peng Gao,Meng Cai,Mengqi Han,Jing Yang,Yiqiang Zhang,Yanlin Song
The improvement of photovoltaic and stability performance of tin (Sn)-based halide perovskite solar cells is impeded by notorious oxidation issues and Anderson localization. Despite previous implements in antioxidation through the incorporation of Lewis base additives, there still exist ongoing uncertainties surrounding its complex interaction mechanisms. A perplexing phenomenon regarding accelerated oxidation in acrylic acid is discovered that deviates from conventional Lewis base–acid reaction. The underlying insights into the deprotonation of acrylic acid followed by the formation of a “tripod” ionic bonding form are provided, which results in amplifying the delocalization effect of electrons of Sn 2+ . Furthermore, with the assistance of acrylamide and acrolein, synergistic enhancement in terms of the antioxidation and suppression of Anderson localization can be achieved — a concept referred to as “Dual Synergistic Engineering”. This suppresses the oxidation of Sn 2+ and reduces Sn 4+ content by ≈76%. Meanwhile, the diffusion length is prolonged significantly from 195.9 to 458.9 nm. The optimized all-inorganic Sn/Pb-based perovskite solar cells exhibit a power conversion efficiency of above 14% with enhanced stability. These findings provide an alternative viewpoint for comprehending the impact of chemical interaction on oxidation and crystal growth in Sn/Pb-based perovskites.
研究领域:
材料科学
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光伏技术
·
钙钛矿太阳能电池
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固体物理
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化学键合
·
半导体材料
✓ 已验证
DOI
高影响因子
危险品化学品经营许可证（带存储）