TRANSITION METAL CHEMISTRY
·
2019
·Vol. 44
·期 8
·779-787
·
IF 1.016
Li Laiming,Li Youxin,Assefa Aschenaki,Bao James J.
Platinum was immobilized on magnetic silica gel by means of boronic, nitric, carboxylic or sulfuric acid ligands to give four heterogeneous Pt nano-catalysts, designated as Fe 3 O 4 @SiO 2 -BA@Pt, Fe 3 O 4 @SiO 2 -NA@Pt, Fe 3 O 4 @SiO 2 -CA@Pt and Fe 3 O 4 @SiO 2 -SA@Pt, respectively. Particles of these mono-dispersible Pt catalysts were 10–20 nm in size and could be separated for recycling by means of a magnet. Fe 3 O 4 @SiO 2 -BA@Pt (0.174 mmol/g Pt) showed the best catalytic activity and selectivity, which were better than Speier’s catalyst. Its turnover numbers were up to 1.7 × 10 6 and 1.1 × 10 6 for hydrosilylation of 1-hexene or styrene, respectively. This material could also catalyze the hydrosilylation of a broad range of alkenes and alkynes as substrates and methyldichlorosilane or triethoxysilane as silanes. Similar yields of 1-hexyl-methyldichlorosilane at the first and eighth runs (96.5% and 95.2%, respectively), together with a final Pt content of 0.171 mmol/g indicated the outstanding stability of Fe 3 O 4 @SiO 2 -BA@Pt under the catalytic reaction conditions.
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高影响因子
JOURNAL OF MATERIALS SCIENCE-MATERIALS IN ELECTRONICS
·
2022
·Vol. 33
·期 30
·23515-23523
·
IF 2.779
Yao Zhongxiang,Bi Gang,Yin Juxin,Chen Zeyu,Cai Chunfeng
Due to the narrow band gap and high quantum confinement effects, Group IV–VI PbSe semiconductor materials have wide applications in infrared detectors. The morphology and size of nanomaterials affect the physical and chemical properties of PbSe semiconductor materials. Here, we developed a synthesized and grew PbSe-branched, I-shaped, and L-shaped nanorods method with uniform distribution by modulating the reaction environment. The results suggested that the arm length of the nanorods increased along the < 100 > axes with reaction time. The directional attachment of nanoparticles along the {100} plane was enhanced by appropriately increasing the reaction temperature. NH 4 Cl could promote the orientational attachment of PbSe nanocrystals along the {100} planes to form I-shaped and L-shaped nanorods. The PbSe-branched nanorod arms were uniformly distributed between 4.2 and 21 nm corresponding to an absorption spectrum between 1086 and 1574 nm and photoluminescence between 1301 and 1621 nm. This indicates that the optical properties are tunable in the near-infrared. Therefore, this research expands the potential applications of PbSe nanostructures in tunable infrared lasers, bioimaging, and solar cells, among others.
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高影响因子
Carbon Letters
·
2020
·Vol. 31
·期 1
·29-37
·
IF 1.992
Wang Qi,Lv Yaying,Zhu Tao
Biomass porous carbons derived from Laminaria japonica were prepared by KOH and H 3 PO 4 activation methods, respectively. The results indicated that the chemical activation had an apparent effect on the molecular framework and space of materials. To enhance the selective adsorption for organic acids, biomass carbons were modified by dopamine combined with N -(2-aminoethyl)-3-aminopropyltrimethoxysilane. The SEM and BET results illustrated the effect of the chemical activation approach on the morphology and porous texture. The biomass porous carbon using KOH activation method had the highest surface area (up to 1558 m 2 /g). Compared with unmodified materials, the modified materials showed higher adsorption capacity for organic acids (27.90 μg/mL for chlorogenic acid and 25.47 μg/mL for caffeic acid). It was suggested that modification of porous carbons might be a viable pathway to increase the specific adsorption affinity and efficiency for organic acids in dried jujube samples.
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高影响因子
Discover Nano
·
2023
·Vol. 18
·期 1
·1-12
·
IF 0
Zhou Houpu,Chen Mengwei,Liu Chenguang,Zhang Rui,Li Jing,Liao Sainan,Lu Haifei,Yang Yingping
Photodetectors (PDs) suffer from dark current due to defects in the perovskite photosensitive layer. Contact between the photosensitive layer and carbon electrodes could result in recombination of carriers at the interface. In this work, CsPbI 3 quantum dots (QDs) were added between the photosensitive layer and the carbon electrode as the interfacial layer to passivate the surface defects of perovskite layer and improve the energy level matching at the interface. The effect of QDs concentrations on the passivation of the perovskite layer was investigated. It was found that the photoluminescence intensity of perovskite films was the strongest and the decay lifetime was the longest when the QDs concentration was 3 mg/mL. Owing to QDs passivation, the dark current of perovskite PD decreased by 94% from \(2.04\; \times \;10^{ - 9}\) to \(1.17\; \times \;10^{ - 10}\) A. The responsivity ( R ) at 605 nm improved by 27% from 0.29 to 0.37 A/W at 0 V bias voltage. The specific detectivity ( D* ) increased by 420% from \(8.9\; \times \;10^{11}\) to \(4.7\; \times \;10^{12}\) Jones.
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Biomass Conversion and Biorefinery
·
2021
·Vol. 13
·期 5
·3871-3880
·
IF 4.987
Zhang Liqiang,Li Shanshan,Yang Zhengda,Wang Xinwei,Li Dawei,Lin Riyi
To explore a new way of utilizing lignin and deepen the understanding of mechanism of two-step pyrolysis (TSP) of biomass, the effects of the first step pyrolysis temperature (T1) and residence time (RT1) on TSP of lignin were studied by using pyrolysis gas chromatography/mass spectrometry (Py-GC/MS). TSP of lignin was also compared with one-step pyrolysis (OSP) of lignin. The results indicated that higher pyrolysis temperature promoted the break of ether linkage among the structural elements of lignin and the removal of side chains. With T1 increasing, the contents of monophenols (MPs), catechols (CPs), monocyclic aromatic hydrocarbons (MAHs), and polycyclic aromatic hydrocarbons (PAHs) increased in the first step, while the contents of methoxyphenols with double bond in the side-chain (MPBSs) and methoxyphenols with no double bond in the side-chain (MPSs) increased firstly and then decreased. In the second step, with T1 increasing the contents of MPs and CPs increased firstly and then decreased, the contents of MAHs and PAHs increased significantly, and the contents of MPBSs and MPSs decreased. Higher T1 increased the yields of the most identified compounds of the first step, but decreased the yields of MPs, CPs, MPBSs, and MPSs in the second step. RT1 had great effects on the pyrolysis behaviors and product distribution of TSP of lignin, and the content of MAHs and PAHs in the second step increased significantly with RT1 increasing. Compared with OSP, the yields of MAHs and PAHs could increase in the second step. TSP of lignin could improve the selectivity of value-added chemicals remarkably, such as guaiacol, vanillin, acetovanillone in the first step, and the selectivity of benzene, toluene, m-xylene, phenol, o-cresol, and p-cresol in the second step.
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高影响因子
JOURNAL OF MATERIALS SCIENCE
·
2021
·Vol. 56
·期 29
·16324-16338
·
IF 4.22
Gao Qiaofeng,Pan Pengju,Shan Guorong,Du Miao
Smart hydrogels have attracted widespread attention and have displayed comprehensive applications in many fields. The development of a novel type of bilayer hydrogel with synergistic function of anisotropic deformation and photochromic property is extremely challenging. Many previous researches have focused on multiple response hydrogels. However, it hardly achieves the synergy of deformation and color-changing through a method with the advantages of simplicity, stability, practicality, and precise control. Herein, a near-infrared light (NIR) photothermal thermoresponsive graphene oxide/poly( N -isopropylacrylamide- β -cyclodextrin) (PNIPAM- β -CD/GO) hydrogel layer and a reversible photochromic ammonium molybdate tetrahydrate/poly( N -isopropylacrylamide- co - β -cyclodextrin) (PNIPAM- β -CD/Mo 7 ) hydrogel layer were combined to obtain a bilayer hydrogel through the host–guest interactions between β -CD and the isopropyl group of NIPAM, exhibiting integrate anisotropic shape deformation and reversible photochromic behaviors. The designed actuators can undergo complex deformation owing to volume shrinkage caused by the photothermal effect under NIR of the PNIPAM- β -CD/GO layer, while the PNIPAM- β -CD/Mo 7 hydrogel layer shows the characteristics of quickly color changing within 5 s when irradiated by a UV light source. The multiple responsiveness of hydrogels on temperature, NIR irradiation, and UV irradiation displays valuable advantages in multifunctional smart materials, such as intelligent soft robots. Graphical abstract
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高影响因子
JOURNAL OF MATERIALS SCIENCE
·
2020
·Vol. 55
·期 24
·10712-10724
·
IF 3.553
Li Wenhua,Chen Qianqiao,Zhong Qin
The nickel sulfide (NiS) nanoparticles were anchored on the mesoporous graphitic carbon nitride (g-C 3 N 4 ) by one-pot calcination with sulfur powder as sulfur source and pore-forming agent. It is the first attempt to use the g-C 3 N 4 /NiS as a counter electrode (CE) for quantum-dot-sensitized solar cells. The g-C 3 N 4 /NiS co-catalyst based on 0.74 wt% NiS loading for S 2− n reduction obtained a low interface charge transfer resistance ( R ct ) of 1.08 Ω. The power conversion efficiency of the QDSSC assembled with ZnSe/CdS/CdSe/ZnSe-sensitized TiO 2 photoanode and g-C 3 N 4 /NiS CE is up to 5.64%, which is 3.05 times as high as that of pure g-C 3 N 4 CE. The enhancement of cell efficiency is attributed to the synergistic effects of excellent morphology of g-C 3 N 4 and its co-catalysis with NiS nanoparticles. The mesoporous architecture contributes a large specific surface area and fast electrolyte transfer channels, and the coupling of g-C 3 N 4 with NiS promotes the transfer of charge between the interface g-C 3 N 4 /NiS and electrolytes. The presented strategy for fabricating mesoporous architecture with g-C 3 N 4 /NiS uses low-cost raw materials and a simple preparation method, which provides a feasible route to enhance the electrocatalytic activity of g-C 3 N 4 .
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高影响因子
Nature Synthesis
·
2022
·Vol. 1
·期 9
·719-728
·
IF 0
Hao Qi,Zhong Hai-xia,Wang Jia-zhi,Liu Kai-hua,Yan Jun-min,Ren Zhou-hong,Zhou Na,Zhao Xiao,Zhang Hao,Liu Dong-xue,Liu Xi,Chen Li-wei,Luo Jun,Zhang Xin-bo
Dual-atom catalysts, combining single-atom catalysts and metal alloys, are promising electrocatalysts for CO 2 reduction but are limited by sluggish CO 2 reduction kinetics and ill-defined dual-atom sites. Here, we develop a catalyst of Ni dual-atom sites via in situ conversion of nanoparticles into dual atoms. We achieve efficient electrocatalytic CO 2 reduction on Ni dual-atom catalysts with a CO partial current density up to ~1 A cm −2 and turnover frequency of 77,500 h −1 at >99% Faradaic efficiency. In situ X-ray absorption and theoretical calculations reveal that during the catalytic process the Ni dual-atom sites trigger the adsorption of hydroxyl (OH ad ), forming electron-rich active centres that endow a moderate reaction kinetic barrier of *COOH formation and *CO desorption. The resultant catalytic microenvironment enables expedited kinetics compared with either the kinetics of bare dual-atom sites or OH ad regulated single-atom sites.
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CELLULOSE
·
2021
·Vol. 28
·期 12
·7953-7968
·
IF 5.044
Xing Xinyi,Li Wenqi,Zhang Jie,Wu Han,Guan Ying,Gao Hui
In this study, the hydrogel was prepared by dissolving and regenerating poplar cellulose in NaOH/urea/water system. The TEMPO-oxidized cellulose hydrogels (TCH) were prepared using microwave-assisted accelerated TEMPO-oxidation system. Polyethyleneimine (PEI) was grafted onto TCH with glutaraldehyde as a cross-linking agent and the products named as TCP. The hydrogels were characterized by SEM, FTIR, XPS, and elemental analyzer. The maximum adsorption capacities of Cu 2+ and Pb 2+ by TCP were 109.89 mg/g and 279.32 mg/g, respectively. TCP was a single molecule adsorption process with better fitting of the Langmuir model. Adsorption kinetics showed that the Pb 2+ adsorption rate of TCP was higher than that for Cu 2+ . The Cu 2+ affinity of TCP was higher than the Pb 2+ . The adsorption capacity of TCP for Cu 2+ and Pb 2+ was 58.26 mg/g and 91.96 mg/g, respectively, after five cycles. This study provided a promising option of preparing an efficient and recyclable adsorbent in treating wastewater containing heavy metal, such as Cu 2+ and Pb 2+ .
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高影响因子
WATER AIR AND SOIL POLLUTION
·
2024
·Vol. 235
·期 1
·1-13
·
IF 3.8
Wang Degui,Xiao Qiuying,Xiao Yepeng,Cheng Lihua,Chen Hong,Chen Bing,Wang Suhua
Since lead is a non-biodegradable and neurotoxic heavy metal, efficient removal of Pb(II) from water is of great significance. Herein, a new type of functional cellulose with enriched thiourea groups (Thiourea-PC) was synthesized using the leaves of plumeria frangipani, a common agricultural solid waste, as the starting materials and applied for the efficient removal of lead ions from water. The properties of the cellulose-based adsorbent have been carefully analyzed and evaluated using FT-IR, SEM, XPS, and elemental analysis techniques. The results showed that the maximum adsorption capacity of Thiourea-PC was 173.92 mg/g under the optimal conditions. The adsorption mechanism was attributed to the complex reaction between Pb(II) and mercaptan/nitrogen-containing groups, and the adsorption process conformed to Langmuir isothermal adsorption model and Pseudo-second-order kinetic model. It is worth noting that after five cycles of adsorption–desorption, the removal rate of Pb(II) by Thiourea-pc was still high, reaching more than 97%, and it had been successfully applied to the simulated adsorption of actual water samples with excellent selectivity. Adsorbent precursors come from a wide range of sources, are economical and effective, and the resource utilization of biomass waste can be realized through sustainable synthesis.
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高影响因子
IONICS
·
2023
·Vol. 29
·期 9
·3459-3471
·
IF 2.8
Ye Wenbin,Lei Jinxuan,Jiang Chaokui,Feng Zuyong,Xiong Deping,He Miao
Large capacity, high rate, and long-term cycling stabilities have always been pursued by lithium-ion batteries (LIBs). In this work, the straightforward hydrothermal and high-speed ball milling programs were employed to create the SnO 2 -NiO-C anode material. NiO nanoparticles with unique hexagonal crystal structure are an ideal choice for ion cycling and embedding, which can stabilize the structure and prevent SnO 2 from becoming coarser. The graphite encapsulated in the outer layer can effectively prevent volume expansion during the cycling as well. From the research results, SnO 2 -NiO-C exhibits a significant reversible capacity of 1224.3 mAh g −1 after 300 cycles at 0.2 A g −1 , and after the fourth cycle, the coulombic efficiency remains above 97%. And it also possesses a long-term cycling stability of 820.1 mAh g −1 after 1000 cycles at 1.0 A g −1 . Also, a significant rate property can reach 507.1 mAh g −1 even at 5.0 A g −1 . Therefore, the SnO 2 -NiO-C anode material for LIBs is promising because of its excellent electrochemical performance.
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高影响因子
RARE METALS
·
2020
·Vol. 39
·期 3
·289-295
·
IF 2.161
Liu Xiao-Cun,Yang Min
AgBi 3 S 5 is a promising n-type thermoelectric material with low lattice thermal conductivity. In this paper, polycrystalline bulk samples of n-type Ag 1− x Sb x Bi 3 S 5 ( x = 0–0.03) were prepared by high-temperature reaction and pressed by spark plasma sintering (SPS). Electrical conductivity of AgBi 3 S 5 is enhanced significantly due to the increased carrier concentration. There is a remarkable enhancement of power factor from ~ 2.1 μW·cm −1 ·K −2 for undoped AgBi 3 S 5 to ~ 3.3 μW·cm −1 ·K −2 for Ag 0.97 Sb 0.03 Bi 3 S 5 . The Sb lone pair electrons, as indicated from density functional theory (DFT) calculation results, contribute to the Fermi energy and enhance the carrier effective mass. In addition, the point defects enhance phonon scattering and decrease the lattice thermal conductivity. Owing to the enhanced power factor and reduced thermal conductivity, the thermoelectric figure of merit ( ZT ) at 800 K for Ag 0.97 Sb 0.03 Bi 3 S 5 reaches 0.53, which is 70% higher than that of the pristine AgBi 3 S 5 .
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高影响因子
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