Solar RRL
·
2021
·Vol. 6
·期 4
·2100995
·
IF 8.582
Chunyan Wang,Jihuai Wu,Shibo Wang,Zhongliang Yan,Xuping Liu,Guodong Li,Liqiang Chen,Sijia Zhu,Weihai Sun,Zhang Lan
Interface engineering has been proven to be an effective method to improve the performance and stability of perovskite solar cells (PSCs). Herein, 5-chloroindole (Cl-indole) is introduced into the interface of a SnO 2 electron transport layer and perovskite light-absorbing layer to improve the photovoltage performance of the device. The results show that Cl−indole can not only form hydrogen bonds with iodine in the perovskite to optimize the interface contact but also coordinate and passivate the Pb 2+ and Sn 4+ interface defects to alleviate carrier nonradiative recombination. Compared with the pristine SnO 2 -based planar PSCs with a power conversion efficiency (PCE) of 20.58%, the Cl−indole-modified SnO 2 -based device achieves a PCE of 22.47%. Meanwhile, the stability of the modified device is effectively improved and the hysteresis effect is reduced. This work demonstrates a promising strategy for high-efficient and stable PSCs by optimizing interface contact and passivating interface defects.
✓ 已验证
产品关联
DOI
高影响因子
ACS Sustainable Chemistry & Engineering
·
2021
·
IF 8.198
Biao Zhu,Yang Qin,Jiawei Du,Fazhi Zhang,Xiaodong Lei
Electrocatalytic biomass valorization with renewable energy input represents a promising way to produce sustainable and non-fossil-based carbon products. The oxidative production of furandicarboxylic acid (FDCA) from bio-based 5-hydroxymethylfurfural (HMF) has attracted one of the most attention. Herein, spinel CuMn2O4 with an urchin-like nanostructure was synthesized by a hydrothermal method and subsequently soaked in ammonia water to create oxygen vacancies. The as-prepared material was used as an efficient electrocatalyst to oxidize HMF to FDCA. It was confirmed that CuMn2O4 etched with ammonia has an excellent electrocatalytic performance: at a current density of 20 mA/cm2, the potential of HMF oxidation was 1.31 V vs RHE in 1.0 M KOH solution with 10 mM HMF prior to the takeoff of the competing reaction, O2 evolution. Long-term chronoamperometry demonstrated that a 100% conversion of HMF and a 96% Faradaic efficiency of yield of FDCA were achieved. Our results indicated that it is feasible to employ the earth-abundant transition metal-based electrocatalyst CuMn2O4 to selectively oxidize biomass with higher energy conversion efficiency than water splitting as well as to produce valuable products in a H-type electrochemical cell.
✓ 已验证
产品关联
DOI
高影响因子
Biomass Conversion and Biorefinery
·
2021
·Vol. 13
·期 12
·10701-10710
·
IF 4.987
Zeng Qin,Du Zhenyu,Luo Ligang
In this study, different bimetallic (Ru, Pd, and Pt) catalysts over a variety of supports (activity carbon, γ-Al 2 O 3 , TiO 2 , HZSM-5) were employed to improve the kraft lignin depolymerization process using isopropanol as in situ hydrogen source. The effect of catalysts was firstly investigated, which suggested that 1wt%Ru-1wt% Pd/HZSM-5 promoted the hydrogenolysis and hydrodeoxygenation effect on conversion of kraft lignin (95.86 wt%) and the selectivity of aliphatic alcohol (26.92 wt%) and hydrocarbon monomers (35.73 wt%), respectively. The effect of temperature and reaction time were also discussed, which indicated that the high temperature (250 to 310 °C) promoted the hydrogenolysis process; while the temperature is higher than 310 °C, the repolymerization process was appeared, leading to the decreasing yield of total monomers. For the influence of reaction time, it was noted that the optimal reaction time to acquired high yield and selectivity of aliphatic alcohol and hydrocarbon monomer was 120 min. It was also conducted FTIR and 2D HSQC NMR analysis to understand the effective depolymerization of the major linkages with attacked by the Ru-Pd/HZSM-5 catalyst, which was corresponding with the results with GC–MS. Graphical abstract
✓ 已验证
产品关联
DOI
高影响因子
Nanoscale
·
2021
·Vol. 14
·期 2
·250-262
·
IF 7.79
Jian Tian,Lixue Qi,Quan Zhang,Guowu Zhan,Daohua Sun,Qingbiao Li
Inspired by the alveolar configuration, an alveoli-like ZSM-5 and the corresponding platinum encapsulated nanocomposite (Pt@PZ5) were fabricated via a dual-template method and a controlled selective desilication–recrystallization strategy. The dimensions of the central cavity, interconnected zeolitic vesicles, and mesoporous shell could be tuned by adjusting the synthesis parameters, as verified by scanning electron microscopy, transmission electron microscopy, nitrogen physisorption investigations, X-ray photoelectron spectroscopy, and X-ray diffraction techniques. Thanks to these properties and merits, the alveoli-like Pt@PZ5 showed the highest catalytic performance with excellent stability, obtaining 100% benzene conversion at 180 °C. Adsorption experiments combined with a finite-element simulation study uncovered that the alveolar architecture could expedite the accumulation of reactants and boost mass transfer; the conversion of intermediates in the voids could be further facilitated, giving optimal catalytic performance. Additionally, the alveolar architecture is resistant to metal sintering (5–20 nm) and leaching, even after calcination at 850 °C for 360 min. This work provides an alveolar concept into the rational design of efficient catalysts for fundamental catalytic action.
✓ 已验证
产品关联
DOI
PubMed
高影响因子
FUEL
·
2021
·
IF 6.609
Guo Qiu,Biaohua Chen,Ning Liu,Chongpin Huang
5-Hydroxymethylfurfural (5-HMF), an important and value-added platform chemical, has inspired increasing attention. In this study, hafnium-tin composite oxides (Sn-HfO 2 ) were prepared by one-pot coprecipitation process and used as effective synergistic catalysts for 5-HMF synthesis from the conversion of glucose. Pyridine-FTIR results reveal that Sn-HfO 2 catalysts have strong Lewis and weak Brønsted acid sites. With 0.5Sn-HfO 2 as the catalyst, the highest yield of 5-HMF obtained from glucose was 75.5% with 99.5% conversion at 170 °C for 2 h in a methyl isobutyl ketone (MIBK)/water biphasic system. Furthermore, the catalytic system also possesses excellent performance in converting other carbohydrates. The catalysis mechanism for the isomerization of glucose to fructose was explored by the density functional theory (DFT) method, indicating that Lewis acidic Hf active sites and proton mediator Sn-O species synergistically catalyzed the isomerization process, effectively lowering the reaction energy barrier. The cooperative action of terminal Hf-OH and Sn-OH also facilitated the formation of 5-HMF in fructose dehydration. 0.5Sn-HfO 2 could be reused for four runs without significant loss of catalytic activity. This approach provides the feasibility of composite oxides as synergistic catalysts for carbohydrate conversion to 5-HMF.
✓ 已验证
产品关联
DOI
高影响因子
FUEL
·
2021
·
IF 6.609
Nai-Yu Yao,Jing-Pei Cao,Jing-Ping Zhao,Zi-Meng He,Xiao-Bo Feng,Tian-Long Liu,Ze-Ying Wang,Xiao-Yan Zhao
A series of Zn-containing HZSM-5 (HZ5) with hierarchical pores (xZn(DS)) were obtained by adding different amounts of Zn(NO 3 ) 2 solution in a hydrothermal synthesis process. The performances of xZn(DS) in catalytic reforming of cellulose pyrolysis volatiles were investigated at 500 °C. The results showed that the addition of Zn during synthesis increased in the total pore volume of xZn(DS) and reduced the content of strong acid sites, and introduced new weak acid sites. The Zn species were highly dispersed inside the zeolite, and enhanced the accessibility of acid sites, so that the yields of light aromatic hydrocarbons and monocyclic aromatic hydrocarbons (MAHs) over 0.7Zn(DS) (The molar ratio of ZnO/Al 2 O 3 in the synthesis process of xZn(DS) was 0.7) were higher than those over S-HZ5 (Zn was not added in the synthesis process) and commercial HZ5. Compared with S-HZ5, the yield of MAHs over 0.7Zn(DS) increased from 92.8 to 114.1 mg/g and the coke yield decreased by 2.9%. The selectivity of MAHs over 0.7Zn(DS) was 87.7%, which was 5.3% higher than that over S-HZ5. Simultaneously, the increase in mesopores of xZn(DS) accelerated the mass transfer process, shortened the diffusion path and improved the anti-coking performance of the catalysts. In addition, this study also proposed a possible mechanism for the catalyst to adjust the distribution of aromatic products and provided a new idea for promoting the selective production of MAHs for the pyrolysis of cellulose.
✓ 已验证
产品关联
DOI
高影响因子
Molecular Therapy-Nucleic Acids
·
2021
·
IF 8.886
Tingyu Zong,Yanyan Yang,Xiaotong Lin,Shaoyan Jiang,Hui Zhao,Meixin Liu,Yuanyuan Meng,Yong Li,Liang Zhao,Guozhang Tang,Kun Gong,Zhibin Wang,Tao Yu
Accumulating evidence shows that tRNA-derived fragments are a novel class of functional small non-coding RNA; however, their roles in aortic dissection (AD) are still unknown. In this study, we found that 5′-tiRNA-Cys-GCA was significantly downregulated in human and mouse models of aortic dissection. The abnormal proliferation, migration, and phenotypic transition of vascular smooth muscle cells (VSMCs) played a crucial role in the initiation and progression of aortic dissection, with 5′-tiRNA-Cys-GCA as a potential phenotypic switching regulator, because its overexpression inhibited the proliferation and migration of VSMCs and increased the expression of contractile markers. In addition, we verified that signal transducer and activator of transcription 4 (STAT4) was a direct downstream target of 5′-tiRNA-Cys-GCA. We found that the STAT4 upregulation in oxidized low-density lipoprotein (ox-LDL)-treated VSMCs, which promoted cell proliferation, migration, and phenotypic transformation, was reversed by 5′-tiRNA-Cys-GCA. Furthermore, 5′-tiRNA-Cys-GCA treatment reduced the incidence and prevented the malignant process of angiotensin II- and β-aminopropionitrile-induced AD in mice. In conclusion, our findings reveal that 5′-tiRNA-Cys-GCA is a potential regulator of the AD pathological process via the STAT4 signaling pathway, providing a novel clinical target for the development of future treatment strategies for aortic dissection.
✓ 已验证
产品关联
DOI
PubMed
高影响因子
SEPARATION AND PURIFICATION TECHNOLOGY
·
2021
·
IF 7.312
Ruixia Yang,Qiaohong Peng,Bing Yu,Youqing Shen,Hailin Cong
Yolk-shell Fe 3 O 4 @MOF-5 nanocomposites were synthesized by utilizing a simple solvothermal method. The physicochemical properties of the yolk-shell Fe 3 O 4 @MOF-5 nanocomposites were characterized by transmission electron microscopy (TEM), Fourier transform infrared spectroscopy (FTIR), X-ray diffraction (XRD), X-ray photoelectron spectroscopy (XPS), Brunauer–Emmett–Teller (BET) and vibrating sample magnetometer (VSM) methods. The nanocomposites had a catalytic yolk, a hollow cavity and a porous shell. The nanocomposites had relatively high specific surface area of 203 m 2 g −1 and showed superparamagnetic property. The catalytic activities of the yolk-shell Fe 3 O 4 @MOF-5 nanocomposites were evaluated by using methylene blue dye as a model pollutant. It is demonstrated that the yolk-shell Fe 3 O 4 @MOF-5 nanocomposites as a heterogeneous Fenton-like catalyst exhibited excellent catalysis since the internal cavity provided a relatively stable micro-environment for the reaction of the active ·OH radicals and the pollutants on the basis of the confinement effect. Furthermore, the yolk-shell Fe 3 O 4 @MOF-5 nanocomposites could be lightly separated from the pollutant solution by an external magnetic field and maintained good catalytic activity after five recycles, indicating the good stability of the nanocomposites.
✓ 已验证
产品关联
DOI
高影响因子
Processes
·
2020
·Vol. 8
·期 10
·1273
·
IF 2.753
Sha Wen,Kai Liu,Yi Tian,Yanping Xiang,Xianxiang Liu,Dulin Yin
2,5-diformylfuran (DFF) is an important downstream product obtained by selective oxidation of the biomass-based platform compound 5-hydroxymethylfurfural (HMF). In this study, a phosphorus-doped carbon (P-C) supported vanadium phosphate oxide (VPO) catalyst was successfully prepared and showed remarkably high catalytic activity in the selective oxidation of HMF to produce DFF with air as an oxidant. The effects of the reaction temperature, reaction time, solvent, catalyst amount, and VPO loading amount were investigated. The results showed that an HMF conversion rate of 100% and a DFF yield of 97.0% were obtained under suitable conditions, and DMSO was found to be the most suitable solvent under an air atmosphere.Keywords:vanadium phosphate oxides;5-hydroxymethylfurfural;catalysis;selective oxidation;2,5-diformylfuran
✓ 已验证
产品关联
DOI
高影响因子
GREEN CHEMISTRY
·
2021
·Vol. 23
·期 5
·2058-2068
·
IF 10.182
Changqu Lin,Chaoqun Chai,Yuanzhang Li,Jiao Chen,Yanyu Lu,Hongli Wu,Lili Zhao,Fei Cao,Kequan Chen,Ping Wei,Pingkai Ouyang
Alkaline earth metal salts are environmentally friendly and economical. They have attracted much attention in the process of biomass conversion, especially for isomerization and dehydration. However, the lack of understanding of the alkaline earth metal-mediated catalytic mechanism prevents the achievement of high HMF yields from glucose or fructose. Herein, we performed experimental and theoretical studies on CaCl2-catalyzed glucose-to-fructose isomerization and fructose-to-HMF dehydration. In CaCl2 solution, the highest fructose yield (33.6%) from glucose can be achieved at 80 °C. Meanwhile, the presence of CaCl2 in fructose-to-HMF dehydration notably improved fructose conversion. A “one-pot” isomerization–dehydration of glucose to prepare HMF was designed and 100% conversion and 52.1% HMF yield were obtained. The CaCl2 solution can be reused for five runs while maintaining catalytic activity without regeneration. Through 1H NMR, 13C NMR, DOSY-NMR and DFT calculations, we concluded that the coordination between the C1/C2 sites of the β-glucopyranose tautomer and CaCl2 promoted the 1,2-intramolecular hydride shift of glucose, thus rapidly converting glucose into fructose. Similarly, Ca2+ can complex with the C2/C6-OH of β-D-fructofuranose and stabilize this tautomer, which easily forms HMF. This is the main reason that CaCl2 can promote the preparation of HMF from fructose.
✓ 已验证
产品关联
DOI
高影响因子
CATALYSIS TODAY
·
2020
·
IF 5.825
Mengmeng Jin,Linhao Yu,Hong Chen,Xueli Ma,Kai Cui,Zhe Wen,Zewei Ma,Yushuai Sang,Mengmeng Chen,Yongdan Li
Ce oxide-based catalysts with different molar ratio of Co/Ce (denoted as CoCe-x, x represents the Co to Ce ratio) were examined as the catalyst of 5-hydroxymethylfurfural (5-HMF) oxidation to 2,5-furandicarboxylic acid (FDCA). The Co to Ce ratio, catalyst amount and reaction temperature all have remarkable effects on yield and selectivity. Complete conversion of 5-HMF with 86.3 % selectivity of FDCA has been achieved over the CoCe-0.15 catalyst at 130 °C with 0.6 MPa O 2 pressure (gauge) for 4 h. The good performance is attributed to the high specific surface area and the high oxygen vacancy concentration to promote the mobility and adsorption of oxygen species. In addition, the CoCe-0.15 catalyst is reused for five times without significant activity loss. Finally, the reaction mechanism over the CoCe-0.15 catalyst under base-free condition is discussed. 5-HMF is oxidized by the lattice oxygen via Mars-van Krevelen mechanism with the redox of Ce 4+ /Ce 3+ and Co 3+ /Co 2+ , and the lattice oxygen is replenished by adsorbing and activating O 2 molecules.
✓ 已验证
产品关联
DOI
高影响因子
Optical Materials Express
·
2020
·Vol. 10
·期 12
·3359-3371
·
IF 3.064
Hefu Li,Hefu Li,Hefu Li,Nan Zhao,Yangzhi Wang,Ruibin Zou,Zhenshan Yang,Changqing Zhu,Minghong Wang,Huishan Yu,Huishan Yu
Nanogap-rich silver nanoislands with fascinating optical properties are desirable substrates for surface-enhanced Raman scattering (SERS). Here, we propose a simple and high-throughput approach through the laser molecular beam epitaxy (LMBE) technique for preparing silver nanoislands containing large numbers of intra-nanogaps on a silicon wafer (6×6 cm2). By optimizing the deposition time, the enlarged silver nanoislands with ∼5 nm interstitial gaps of abundance and homogeneity were formed. Remarkably, the optimized SERS substrate with high-density hotspots demonstrated a high analytical enhancement factor (AEF) as large as 1.17×105, excellent reproducibility with relative standard deviation (RSD) of 7.76% over the entire substrate, and good stability after storage for 21 days. The electromagnetic field distribution of the optimized SERS substrate was simulated using the software COMSOL Multiphysics based on the actual SEM image of the fabricated sample, and the calculated enhancement factor (EF) is as high as 109. Furthermore, it can enable sensitive and quantitative detection of malachite green at concentrations as low as 10−8 M. This simple fabrication of silver nanoislands with homogeneous ∼5 nm interstitial gaps provides a practical solution for wafer-scale, sensitive, and reproducible SERS substrates.
✓ 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）