MATERIALS CHEMISTRY AND PHYSICS
·
2020
·
IF 3.408
Yanling Cheng,Kexu Li,Shihong Wei,Hainan Zhang,Shengkai Yang,Xiong Huang,Sidney Lin,Kevin P. Plucknett,Huatay Lin
Nano-sized AlN powders were successfully synthesized using a wet chemical route, with dicyandiamide as the nitrogen source reagent. The influence of dicyandiamide/metal precursor molar ratio on the purity, crystallization, microstructure, and optical properties of the calcined powders were studied. The underlying reaction mechanisms, along with the intermediates formed during the reactions, were also investigated. The compositions and morphologies of the as-received and prepared powders were subsequently characterized using XPS , FTIR , XRD , SEM, and TEM. The optical properties of the prepared powders were measured by ultraviolet–visible spectroscopy (UV–Vis). The precursor components decompose, and follow a complex reaction sequence as a function of temperature, finally leading to AlN formation at 800 °C. Increasing AlN content is achieved between 800 and 890 °C. Essentially only AlN arises following calcination at 900 °C. The AlN crystallite size and degree of crystallization further increase when calcining at 1000 °C. This work demonstrates a promising route to produce nano-sized AlN powders with favorable microstructures and optical properties.
研究领域:
材料科学
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化学
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DOI
高影响因子
JOURNAL OF COLLOID AND INTERFACE SCIENCE
·
2023
·
IF 9.9
Miao Fu,Liuquan Lin,Xin Wang,Xiaoming Yang
Achieving the long-lived and strong room-temperature phosphorescence (RTP) is challengeable but desirable, especially for the enhanced phosphorescence and metal-free nanomaterials. Herein, we initially synthesized the green-fluorescence carbon dots (pm-CDs), and further obtained the composite of pm-CDs@DCDA with a long RTP lifetime of 1.01 s through embedding pm-CDs in dicyandiamide (DCDA). And the bright and long-lived afterglow of pm-CDs@DCDA with 365 nm of UV light excitation was observed by the naked eyes for more than 17 s either emerging as the dry solid or in water. Importantly, the phosphorescence intensity and lifetime of pm-CDs@DCDA were remarkably promoted owing to the intermolecular hydrogen bonds and the rigid environment, hence facilitating the intersystem crossing (ISC) process and restricting the non-radiative transition of triplet excitons. Taking advantage of the superior solid-state luminescence of pm-CDs@DCDA, we further innovatively prepared the white light-emitting diodes (WLEDs) with the tunable color temperatures by regulating the mass of pm-CDs@DCDA coated on the chips. This proposed study originally employed DCDA as a matrix to separate and immobilize pm-CDs, which built up a new avenue to improve the RTP property and offered a promising application in WLEDs.
研究领域:
材料科学
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光学
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产品关联
DOI
PubMed
高影响因子
JOURNAL OF MATERIALS RESEARCH
·
2024
·
IF 2.7
Shen Wenting,Du Jiaxin,Mei Xiangyu,Liu Su,Liu Fujian,Si Yinsong
Graphitic carbon nitride (g-C 3 N 4 ), owing to its unique structure, has emerged as a hotspot in the semiconductor photocatalytic hydrogen production. However, the intrinsic poor crystallinity of g-C 3 N 4 , which leads to poor hydrogen production efficiency, remains a significant drawback. This study introduces a novel approach for synthesizing highly crystallized g-C 3 N 4 by optimizing precursor mass and employing a fixed temperature polymerization technique. Our research focuses on the intermediate stage polymerization at 220 °C using varying masses of dicyandiamide (DCY) precursors. The results indicate that an increase in the mass of the DCY precursor leads to g-C 3 N 4 with a more regular microstructure and enhanced crystallinity. The photocatalytic hydrogen production rate of this g-C 3 N 4 reached up to 3779 μmol·h −1 ·g −1 , which is five times that of the original g-C 3 N 4 .This research holds significant implications for improving the photocatalytic hydrogen production performance of intrinsic g-C 3 N 4 . Graphical abstract
研究领域:
材料科学
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能源化学
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产品关联
DOI
高影响因子
Catalysts
·
2025
·Vol. 15
·期 5
·459
·
IF 4
Dan Wang,Yanan Liu,Kun Wan,Danning Feng,Yan Pei,Minghua Qiao,Xiaoxin Zhang,Baoning Zong
The electrocatalytic reduction of O2via two-electron reaction (2e-ORR) to H2O2represents a promising alternative to the current anthraquinone process, since it is advantageous in the sustainable and decentralized production of H2O2. Herein, we report the development of oxygen and nitrogen-rich few-layered graphene-like materials (ms-dcda) by the one-step carbonization of biomass-sourced monosaccharides (D-glucose, D-fructose, D-galactose, D-ribose, D-xylose, L-arabinose, and D-mannose) with the aid of dicyandiamide for electrochemical O2reduction to H2O2. The ms-dcdamaterials were porous and possessed wrinkled morphology typical of graphene nanosheets. In H2O2production via 2e-ORR in an acidic electrolyte, these ms-dcdamaterials were all active and stable catalysts, among which glu-dcdaderived from D-glucose and dicyandiamide displayed the lowest onset potential of 0.553 V and the highest selectivity of up to 91.6%. The catalyst was also highly stable in chronoamperometric tests. Selective chemical titration of the C–OH and C=O groups revealed that the latter is far more active and selective than the former in 2e-ORR. Moreover, a positive correlation between the contents of C=O and pyrrolic N and the H2O2partial current suggests that the pyrrolic N group also contributes to 2e-ORR. This work affords a facile strategy for the sustainable fabrication of metal-free carbon-based catalysts efficient for H2O2electrosynthesis.
研究领域:
材料科学
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电化学
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催化
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产品关联
DOI
高影响因子
FOOD CHEMISTRY
·
2017
·
IF 4.529
Hongwu Wang,Yanqing Liu,Su Yao,Peijie Zhu
In this work, a highly selective molecular imprinted polymer (SBA-15@MIP) was prepared using dicyandiamide (DCD) as the template molecule and mesoporous silica SBA-15 as the carrier. The resulting polymers were characterized by scanning electron microscopy and FT-IR spectra. A highly ordered mesoporous nanostructure was observed for the fabricated polymer. The performance tests showed that the adsorption capacity of SBA-15@MIP for DCD was higher than those of non-imprinted mesoporous silica polymer (SBA-15@NIP) and SBA-15. SBA-15@MIP was successfully used as the solid-phase extraction (SPE) sorbent coupled with HPLC for trace DCD determination in bovine milk and milk powder. Under selected conditions, a favorable linearity between 1 μg/mL and 100 μg/mL was obtained and the detection limit was estimated to be 0.08 μg/mL (bovine milk) and 0.10 μg/mL (milk powder). These results indicated that SBA-15@MIP could be used as an efficient SPE adsorbent for enrichment of DCD in bovine milk and milk powder.
研究领域:
分析化学
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食品科学
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产品关联
DOI
PubMed
高影响因子
INTERNATIONAL JOURNAL OF MOLECULAR SCIENCES
·
2016
·Vol. 17
·期 11
·1750
·
IF 3.257
Dadong Liang,Yan Wang,Songyang Li,Yuqing Li,Miliang Zhang,Yang Li,Weishuai Tian,Junbo Liu,Shanshan Tang,Bo Li,Ruifa Jin
With the aid of theoretical calculations, a series of molecularly imprinted polymers (MIPs) were designed and prepared for the recognition of dicyandiamide (DCD) via precipitation polymerization using acetonitrile as the solvent at 333 K. On the basis of the long-range correction method of M062X/6-31G(d,p), we simulated the bonding sites, bonding situations, binding energies, imprinted molar ratios, and the mechanisms of interaction between DCD and the functional monomers. Among acrylamide (AM),N,N’-methylenebisacrylamide (MBA), itaconic acid (IA), and methacrylic acid (MAA), MAA was confirmed as the best functional monomer, because the strongest interaction (the maximum number of hydrogen bonds and the lowest binding energy) occurs between DCD and MAA, when the optimal molar ratios for DCD to the functional monomers were used, respectively. Additionally, pentaerythritol triacrylate (PETA) was confirmed to be the best cross-linker among divinylbenzene (DVB), ethylene glycol dimethacrylate (EGDMA), trimethylolpropane trimethylacrylate (TRIM), and PETA. This is due to the facts that the weakest interaction (the highest binding energy) occurs between PETA and DCD, and the strongest interaction (the lowest binding energy) occurs between PETA and MAA. Depending on the results of theoretical calculations, a series of MIPs were prepared. Among them, the ones prepared using DCD, MAA, and PETA as the template, the functional monomer, and the cross-linker, respectively, exhibited the highest adsorption capacity for DCD. The apparent maximum absorption quantity of DCD on the MIP was 17.45 mg/g.Keywords:dicyandiamide;molecular imprinting;molecularly imprinted polymer;computer simulation
研究领域:
化学
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材料科学
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计算化学
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产品关联
DOI
PubMed
高影响因子
THERMOCHIMICA ACTA
·
2025
·
IF 3.5
Yuxin Yang,Chunhua Lou,Huixiao Wang,Jingjing Yu
In this study, dicyandiamide (DCD) was modified with o-aminoacetophenone to synthesize a new curing agent for epoxy resin (EP), called o-acetylphenylguanidine (o-APG). The experimental results showed that the yield of o-APG could reach 85.79% under the optimal ratio. The structure of o-APG was characterized via Fourier transform infrared spectroscopy, X-ray photoelectron spectroscopy, X-ray diffraction analysis, and nuclear magnetic resonance spectroscopy. The result deduced that the compatibility of o-APG with EP was significantly improved because reacted to form the group. The curing kinetics of the reaction of EP cured with o-APG was investigated via differential scanning calorimetry (DSC) by using the methods of Kissinger, Ozawa, Starink, and Friedman. The DSC analysis result showed that curing temperature was reduced by about 50 °C compared with the DCD-cured EP.
研究领域:
材料科学
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化学工程
✓ 已验证
产品关联
DOI
高影响因子
FOOD CHEMISTRY
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2020
·
IF 6.306
Abid Hussain,Da-Wen Sun,Hongbin Pu
Existing methods for contaminants detection in liquid milk are complex, requires chemicals and time-consuming experimental procedure. In this study, SERS based on bimetallic core shelled nanoparticles was employed for simultaneous and fast detection of thiram and dicyandiamide (DCD) in the milk. Spectra ranging from 400 to 1700 cm −1 were selected to examine thiram (0.5, 1, 2, 5 and 10 ppm) and DCD (20, 40, 80,160 and 320 ppm), by employing 28 nm gold cores and silver-shell thickness of 8 nm. A strong peak at 1379 cm −1 was ascribed to thiram with LOD of 0.21 ppm and R 2 of 0.9896, whereas a band at 929 cm −1 was associated with DCD, delivering LOD of 14.88 ppm and R 2 of 0.9956. The proposed method could achieve results within 34 min and this ecofriendly method can be further employed for simultaneous and rapid screening of other accidental contaminants in milk.
研究领域:
分析化学
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食品科学
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环境科学
✓ 已验证
产品关联
DOI
PubMed
高影响因子
MICROPOROUS AND MESOPOROUS MATERIALS
·
2021
·
IF 5.455
Wei Wu,Wei Zhang,Yu Long,Jiaheng Qin,Jiantai Ma
Carbon material derived from certain MOF usually still has plenty of microporous structures, the mass transfer process is severely limited. In this work, in the assistance of dicyandiamide, nitrogen doped carbon confined atomically dispersed Fe species (Fe–N–C) with interconnected mesoporous pores by a facile one-step pyrolysis process of Fe-doped zeolitic imidazolate framework (Fe-doped ZIF) is prepared. Through simply adjusting the amount of dicyandiamide added, Fe–N–C with various morphologies, pore structures and chemical compositions could be obtained. The specific surface area of the materials increases first and then decreases with the increase content of dicyandiamide, and the pore structure also changes accordingly. Fe–N–C possesses the largest specific surface area with interconnected pore structure when the mass ratio of dicyandiamide to Fe-doped ZIF reaches 1:1 (Fe–N–C–1). And Fe–N–C–1 shows the optimal catalytic activity compared with other catalysts for the transfer hydrogenation of halonitrobenzenes. Moreover, the Fe–N–C–1 exhibits good stability and could be reused without obvious decrease of catalytic activity. This work may afford certain thought for rationally designing high-performance catalysts derived from MOF .
研究领域:
材料科学
·
催化化学
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DOI
高影响因子
ANALYST
·
2022
·Vol. 147
·期 23
·5324-5333
·
IF 5.227
Jie Zhang,Xue-Ji Zhang,Serge Cosnier,Dan Shan
In the rapid development of artificial nanomaterials comparable to biological enzymes, we propose herein a novel concept for the construction of functional materials inspired from chemical evolution. To mimic the formation process of the catalytic system for the origin of life, dicyandiamide (DCD) was used as an elemental molecule for the de novo synthesis of an electrocatalyst. DCD was initially condensed with glucose (Glu) to form carbon dots (CDs) via a hydrothermal method. The self-assembly of the DCD-derived CDs was then modulated by introducing copper ions and a controlled pyrolysis process. Carbonization of the self-organized DCD-CDs/Cu at 300 °C in air produced the resultant catalyst (DCD-CDs/Cu-300) with the crystalline properties of a transitional state from an organic to inorganic matter, possessing a well-tuned chemical composition and the enhanced electrochemical signal of H2O2 reduction. Therefore, the DCD-CDs/Cu-300 modified electrode provides satisfactory analytical performance for trace H2O2 quantification with a wider linear range (1.0 × 10−7 to 1.4 × 10−3 M) and low detection limit (6.4 × 10−8 M, S/N = 3). This facile electrocatalyst construction strategy inspired from chemical evolution is expected to pave the way to form a more unified paradigm by integrating nanotechnology.
研究领域:
材料科学
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分析化学
·
仿生学
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DOI
高影响因子
Nano-Micro Letters
·
2025
·Vol. 17
·期 1
·1-14
·
IF 36.3
Chen Ge,Gan Yunlong,Wang Shiheng,Liu Xueru,Yang Jing,Peng Sihui,Zhao Yingjie,Li Pengwei,Komilov Asliddin,Song Yanlin,Zhang Yiqiang
Organic–inorganic hybrid perovskite solar cells achieve remarkable efficiencies (> 26%) yet face stability challenges. Quasi-2D alternating-cation-interlayer perovskites offer enhanced stability through hydrophobic spacer cations but suffer from vertical phase segregation and buried interface defects. Herein, we introduce dicyanodiamide (DCD) to simultaneously address these dual limitations in GA(MA) n Pb n I 3n+1 perovskites. The guanidine group in DCD passivates undercoordinated Pb 2+ and MA + vacancies at the perovskite/TiO 2 interface, while cyano groups eliminate oxygen vacancies in TiO 2 via Ti 4+ –CN coordination, reducing interfacial trap density by 73% with respect to the control sample. In addition, DCD regulates crystallization kinetics, suppressing low-n-phase aggregation and promoting vertical alignment of high-n phases, which benefit for carrier transport. This dual-functional modification enhances charge transport and stabilizes energy-level alignment. The optimized devices achieve a record power conversion efficiency of 21.54% (vs. 19.05% control) and retain 94% initial efficiency after 1200 h, outperforming unmodified counterparts (84% retention). Combining defect passivation with phase homogenization, this work establishes a molecular bridge strategy to decouple stability-efficiency trade-offs in low-dimensional perovskites, providing a universal framework for interface engineering in high-performance optoelectronics.
研究领域:
材料科学
·
能源化学
·
纳米技术
·
光电工程
✓ 已验证
产品关联
DOI
PubMed
高影响因子
JOURNAL OF POLYMER SCIENCE PART A-POLYMER CHEMISTRY
·
2013
·Vol. 52
·期 3
·375-382
·
IF 3.543
Chun Hua Zhao,Shun Jiang Wan,Lu Wang,Xiang Dong Liu,Takeshi Endo
This study investigates the curing of epoxidized soybean oil (ESO) using dicyandiamide (DICY) and combinations of DICY with several accelerators as curing agents. The differential scanning calorimetry (DSC) results indicated that carbonyldiimidazole (CDI) is a highly efficient accelerator for the ESO-DICY curing system. CDI accelerated ESO-DICY curing system can gel within a short period of 13 min at 190 °C. The activation energies of the ESO-DICY curing systems with and without CDI are 95 and 121 kJ mol −1 , respectively. Similar acceleration effect was observed in the ESO-diglycidyl ether of biphenyl A (DGEBA) blending formulations. When the molar part of the glycidyl epoxy groups of DGEBA was equal to the internal epoxy groups of ESO in the mixture, gelation of the DICY curing system accelerated by CDI was achieved in 3 min at 160 °C. Furthermore, the DSC results with FTIR analysis suggest that the stoichiometric curing molar ratio was 3 ESO epoxy units per 1 DICY molecule. Two epoxy units reacted with DICY to give secondary alcohols, while the other one linked to the nitrile group. © 2013 Wiley Periodicals, Inc. J. Polym. Sci., Part A: Polym. Chem. 2014 , 52 , 375–382
研究领域:
材料科学
·
化学工程
✓ 已验证
DOI
高影响因子
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