MOLECULAR CRYSTALS AND LIQUID CRYSTALS
·
2022
·
IF 0.672
Limin Wu,Jinming Chu,Fei Wang,Wei Liu,Yongmin Guo,Yi Li,Baozong Li,Yonggang Yang
A series of azobenzene liquid crystals containing one amino acid residue were synthesized. They exhibit smectic mesophases. The compounds derived from alanine can self-assemble into twisted nanoribbons. The molecules organized in a monolayer structure within the nanoribbon. Circular dichroism characterization indicated that the neighboring liquid crystal cores packed in a chiral structure. FT-IR spectra indicated that the nanoribbons were caused by H-bonding and association of hydrocarbon chains.
研究领域:
材料科学
·
生物化学
✓ 已验证
产品关联
DOI
高影响因子
CHEMICAL ENGINEERING JOURNAL
·
2024
·
IF 13.3
Yuan Cao,Yao Wu,Yiming Huang,Hongping Xiang,Lanyue Zhang
4D printing, combining the advantages of 3D printing and stimuli-responsive materials, provides a precise and rapid fabrication method for complex-shaped smart objects. In this study, the photoisomerization characteristic of azobenzene is used to develop 4D printable resins composed of azobenzene-based acrylates (AZO) and other acrylate compounds, which can be UV-cured and 3D printed into objects with photo and thermal dual responsiveness. UV-curing kinetics reveal that AZO competes with the photoinitiator for photons during photopolymerization, reducing the generation of reactive oxygen species and subsequently affecting the mechanical properties of UV-cured resin. The optimum content of AZO in 4D printing resins is 0.5 wt%, producing 3D printed objects with excellent mechanical properties, including a maximum stress of 25.2 MPa and a strain of 100 %. This ensures the successful formation of complex-shaped objects in the 3D printing process. Moreover, the objects printed with this photosensitive resin demonstrate exceptional shape memory capabilities, achieving a 100 % shape recovery ratio over three cycles of thermal stimulation. The printed openwork spheroid with a concave shape can successfully revert to its original form after 48 s of irradiation with 365 nm UV light. The degree of shape recovery can be precisely controlled by adjusting the UV irradiation time and position. Therefore, these photo/thermal dual-responsive 4D objects show great application prospects in medical devices and smart materials.
研究领域:
材料科学
·
化学工程
✓ 已验证
产品关联
DOI
高影响因子
MACROMOLECULAR CHEMISTRY AND PHYSICS
·
2019
·Vol. 220
·期 12
·1900061
·
IF 2.622
Liang Zhao,Lin Zhang,Zelai Zheng,Ying Ling,Haoyu Tang
Homopolypeptide bearing azobenzene and triethylene glycol spacers, and 1-butylimidazolium pendants, namely P(Azo-OEG 3 -ImX) (X = Cl, I, BF 4 ) are prepared by 1,3-dipolar cycloaddition and subsequent ion-exchange reaction. Both 1 H NMR and FTIR confirm the polymer structures and reveal a high grafting efficiency (97%). P(Azo-OEG 3 -ImI) shows reversible upper critical solution temperature (UCST)-type thermoresponsive property in ethanol while P(Azo-OEG 3 -ImI/BF 4 ) shows a UCST in ethanol/water solvent mixtures. P(Azo-OEG 3 -ImI) shows UCST-type phase transitions in ethanol or ethanol/water solvent mixtures. After UV irradiation, the UCST-type cloud point temperature ( T cp ) remains constant in ethanol. However, it decreases after UV irradiation and increases after visible light irradiation in ethanol/water solvent mixtures due to the trans – cis isomerization of azobenzene moieties. P(Azo-OEG 3 -ImCl/I) shows NaI-induced UCST in water. The T cp of the P(Azo-OEG 3 -ImCl/I) aqueous solution is highly related to the polymer/salt concentration and nature of counteranions. P(Azo-OEG 3 -ImCl) also shows reversible light-responsive properties in NaI aqueous solutions. Higher NaI concentration is needed to induce a UCST for P(Azo-OEG 3 -ImCl) after UV irradiation. Moreover, ciprofloxacin-loaded hydrogel containing P(Azo-OEG 3 -ImCl) shows more efficient drug release while the UV irradiation leads to slightly low drug release.
研究领域:
高分子化学
·
材料科学
✓ 已验证
DOI
高影响因子
ACS Applied Materials & Interfaces
·
2020
·
IF 8.758
Hairus Abdullah,Yu-Rou Ko,Dong-Hau Kuo,Noto Susanto Gultom
La–Sn-codoped Zn(O,S) catalysts were synthesized with different amounts (0%, 2.5%, 5%, and 10%) of Sn and a constant amount (10%) of La to improve the photocatalytic hydrogenation reaction (PHR) of azobenzene to aniline. The as-prepared catalysts were carefully characterized and tested for a hydrogenation reaction. The incorporation of Sn significantly enhanced the PHR activities since the incorporated Sn in the Zn(O,S) lattices could increase the conductivity of the catalysts to improve the charge transfer during the catalytic reaction as indicated with EIS measurement. Further measurement with a photoresponse of La–Sn-codoped Zn(O,S) catalysts also exhibited relatively higher intensities as compared to those of La-doped Zn(O,S) and Sn-doped Zn(O,S) catalysts. On the basis of the measurement results of EIS and transient photo current, the La–Sn-codoped Zn(O,S) with the best properties was further utilized for PHR to convert azobenzene to aniline. GC–MS measurement confirmed that 15 ppm azobenzene could be totally converted to aniline in only 60 min which was achieved with a catalyst that was prepared with 5%-Sn and 10%-La doping. The relatively short reaction time indicated that the as-prepared catalyst had a strong reduction capability able to cleave the strong bonding of N═N in azobenzene. The reaction kinetic of the N═N bond cleavage was elucidated based on solvation, adsorption, pinning, and photocatalytic hydrogenation processes on the catalyst surfaces.
研究领域:
材料科学
·
环境科学
·
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
Jiaxin Li,Ganceng Yang,Yanqing Jiao,Hongyan Sun,Jiaqi Wang,Yue Liu,Chungui Tian,Haijing Yan,Honggang Fu
Selective electroreduction of nitrobenzene (NB) to generate valuable azoxybenzene (AOB) is an important electrochemical N-N coupling reaction, but suffering from low selectivity at low potential. Herein, we constructed a Mo-incorporated NiFe bimetallic nitride on nickel foam (Mo-Fe 2 Ni 2 N/NF), effectively catalyzing selective electroreduction of NB (NSR) to generate AOB. Experimental and theoretical findings reveal that incorporating Mo into Fe 2 Ni 2 N triggers a rational charge redistribution, which induces a moderate hydrogen affinity, alongside enhances the adsorption of nitrosobenzene and phenylhydroxylamine intermediates so as to lower energy barrier of potential-determining step (PDS) for formation of AOB and higher energy barriers of PDS for formation of by-products (amine and azobenzene) can be achieved, thus leading to desired tandem reactions of partial hydrogenation reduction and bimolecular coupling for selective electrosynthesis of AOB. As a result, Mo-Fe 2 Ni 2 N/NF exerts an ultralow potential (0.341 V@100 mA cm −2 ) along with 100 % conversion of NB and 97.2 % yield of AOB. Remarkably, an anion exchange membrane flow electrolyzer of pairing cathodic NSR with anodic benzylamine oxidation by using Mo-Fe 2 Ni 2 N/NF cathode and Mo x Ni y N/NF anode is integrated, and simultaneous synthesis of value-added, easy-separation AOB and benzonitrile can be accomplished with low voltage (1.50 V@100 mA cm −2 ) and high productivity (> 90 %), highlighting its large potential for industrial application. This work showcases a new route to design efficient electrocatalysts for organic electrosynthesis via manipulating adsorption of key reaction species of constructing multicomponent nitrides.
研究领域:
材料科学
·
电化学
·
有机合成
✓ 已验证
产品关联
DOI
高影响因子
CRYSTENGCOMM
·
2012
·Vol. 15
·期 7
·1339-1344
·
IF 3.842
Wei Wang,Zhenyu Feng,Wei Jiang,Jinhua Zhan
Porous CuO–Ag nanofibers have been synthesized via a combination of the electrospinning technique and the PVP-assisted sol–gel technique in the absence of any templates. The thermal behavior of the as-spun fibers was characterized by TG-DSC while FT-IR was employed to prove the removal of the polymer, which resulted in a porous structure. The structure and morphology of the resultant products were characterized by XRD, TEM and SEM. Porous CuO–Ag nanofibers fabricated on a Si substrate exhibited large Raman enhancement ability, which was also investigated. The SERS signals on the obtained substrate had perfect temporal stability under continuous laser radiation and a good uniform response, enabling quantitative detection of analyte azobenzene. The log–log plot of the SERS intensity to the azobenzene concentration exhibited a good linear relationship.
研究领域:
材料科学
·
分析化学
✓ 已验证
产品关联
DOI
高影响因子
MOLECULES
·
2023
·Vol. 28
·期 2
·877
·
IF 4.6
Xuan Chen,Siyu Fang,Ping Xue,Jiming Huang,Mi Tang,Zhengbang Wang
The development of tunable molecule separation membranes requires materials with remote controllability and ultra-high separation capability. In this paper, a novel photoswitchable metal organic framework (MOF) thin film (Cu2(AzoBPDC)2) was prepared by liquid phase epitaxial layer-by-layer assembly to realize the reversible remote-controlled switching. The azobenzene side groups in the Cu2(AzoBPDC)2thin film showed excellent reversible photoswitching performance under UV (365 nm) and Vis (450 nm) irradiation, achieving the remote-controlled mode of the diffusion flux of polar gas molecules in the MOF thin film.Keywords:metal–organic frameworks;azobenzene;photoswitchable;gas separation
研究领域:
材料科学
·
化学工程
·
光化学
✓ 已验证
DOI
PubMed
高影响因子
Materials Research Express
·
2016
·Vol. 3
·期 11
·115701
·
IF 0.968
Si Chen,Yining Chen,Xiaoqian Tong,Bozhen Wu,Meng Ma,Yanqin Shi,Xu Wang
A room temperature optical image storage device based on a novel kind of chiral azobenzene liquid crystal compound (Azo-CC) dopant was reported in this paper, which could realize room temperature photocatalytic phase transition when doping in host liquid crystal E7. With a comparation of the referential achiral compound (Azo-ACC), the chemical structure, liquid crystalline and photoresponsive properties of the compounds were characterized by 1H-NMR, POM and UV–vis, respectively. The result showed that the compound with chiral group (Azo-CC) exhibited better photoresponsive properties than the referential achiral compound (Azo-ACC), indicating the introduction of chiral group is the key factor to provide E7 host room temperature photosensitive properties, which could not only made the liquid crystal molecular reoriented but also could change the whole nematic host liquid crystal to helical-twisted matrix. In addition, to understand the optical-switching behavior into detail, the photoisomerization dynamics of the systems o was also analyzed.
研究领域:
材料科学
·
光学
✓ 已验证
DOI
高影响因子
Polymers
·
2017
·Vol. 9
·期 7
·287
·
IF 3.364
Jinghao Yang,Hao Wen,Haitao Zhuo,Shaojun Chen,Jianfeng Ban
In this paper, we developed a photo-thermo staged-responsive shape-memory polymer network which has a unique ability of being spontaneously photo-responsive deformable and thermo-responsive shape recovery. This new type of shape-memory polyurethane network (A-SMPUs) was successfully synthesized with 4,4-azodibenzoic acid (Azoa), hexamethylenediisocyanate (HDI) and polycaprolactone (PCL), followed by chemical cross-linking with glycerol (Gl). The structures, morphology, and shape-memory properties of A-SMPUs have been carefully investigated. The results demonstrate that the A-SMPUs form micro-phase separation structures consisting of a semi-crystallized PCL soft phase and an Azoa amorphous hard phase that could influence the crystallinity of PCL soft phases. The chemical cross-linking provided a stable network and good thermal stability to the A-SMPUs. All A-SMPUs exhibited good triple-shape-memory properties with higher than 97% shape fixity ratio and 95% shape recovery ratio. Additionally, the A-SMPUs with higher Azoa content exhibited interesting photo-thermo two-staged responsiveness. A pre-processed film with orientated Azoa structure exhibited spontaneous curling deformation upon exposing to ultraviolet (UV) light, and curling deformation is constant even under Vis light. Finally, the curling deformation can spontaneously recover to the original shape by applying a thermal stimulus. This work demonstrates new synergistically multi-responsive SMPUs that will have many applications in smart science and technology.Keywords:azobenzene;polyurethane;shape memory;photo;responsiveness
研究领域:
材料科学
·
高分子化学
✓ 已验证
产品关联
DOI
PubMed
高影响因子
Journal of Physical Chemistry C
·
2023
·
IF 3.7
Ting Qu,Xue Hu,Ying Ou,Jie Wang,Fuqiang Hu,Jing Ni,Fan Cheng,Chunli Gong,Hai Liu
Robust metallic doped semiconducting networks of precise organization, over large scales and small dimensionality, hold great application potential in the basis of photocatalytic materials. Herein, a facile method to fabricate robust Au@TiO2 hierarchical nanoporous network films is reported, which is templated by thermally stable poly(4-vinylpyridine)-block-poly{11-[4-(4-butylphenylazo)phenoxy]undecyl methacrylate} (P4VP-b-PMA(11C)Az) liquid crystalline (LC) block copolymers (BCPs). A P4VP100-b-PMA(11C)Az15 thin film can self-assemble to form ∼50 nm orderly packed PMA(11C)Az periodic spheres in the P4VP matrix via a solvent-annealing process. When these spherical P4VP100-b-PMA(11C)Az15 films with different thicknesses were exposed to the sol–gel titania precursors alcohol solutions with titanium(IV) isopropoxide (TIPT) and titanium tetrachloride (TiCl4; mass ratio, 3:1), titania was well-formed in the P4VP phase during the calcination process. After a further deposition–precipitation (DP) process, ∼10 nm Au nanoparticles were homogeneously doped in robust TiO2 nanoporous network films. The photocatalytic performance of the obtained robust Au@TiO2 films was studied in detail. It displays significantly enhanced visible light photocatalytic activity. The enhancement mechanism was ascribed to the injection of hot electrons of photoexcited Au nanoparticles to robust porous TiO2 films, which was confirmed by 420 nm Xe laser-induced fast photodegradation of rhodamine B.
研究领域:
材料科学
·
化学工程
·
纳米技术
✓ 已验证
产品关联
DOI
高影响因子
EUROPEAN POLYMER JOURNAL
·
2018
·
IF 3.741
Xia Xia,Haojie Yu,Li Wang,Zheng Deng,Kenneth J. Shea,Zain-ul-Abdin
A series of redox- and photo-responsive copolymers, poly(2-(methacryloyloxy)ethyl ferrocenecarboxylate- co -4-methacryloylamino-4′-nitroazobenzene) (P(FcEMA- co -MAAzo)s) were synthesized using free radical polymerization. The synthesized copolymers were characterized by 1 H NMR, FT-IR, gel permeation chromatography (GPC) and thermogravimetric analysis (TGA). Cyclic voltammetry (CV) and Ultraviolet–visible (UV–vis) absorption studies showed redox- and photo-responsive properties of the synthesized copolymers in the solution. P(FcEMA- co -MAAzo)s films were prepared by spin-coating or drop-coating method and these films were found to be redox- and photo-responsive. The color of the prepared films could be adjusted by the redox stimulus, while UV–vis absorption properties of the prepared films could be adjusted by changing wavelength of light. It was found that these synthesized films show potential application for high density information storage.
研究领域:
材料科学
·
化学
✓ 已验证
DOI
高影响因子
RSC Advances
·
2024
·Vol. 14
·期 8
·5417-5424
·
IF 3.9
Jie Yi,Yajing Yang,Xi-ming Song,Yuxuan Zhang
Azobenzene-containing poly(aryl ether)s are a potential type of photoinduced deformable high-performance polymer. However, research on photoinduced deformation of azobenzene-containing poly(aryl ether)s focuses mainly on poly(aryl ether)s containing azobenzene groups in the main chain. In this paper, the photoinduced deformation of poly(aryl ether)s containing azobenzene groups in the side chain was studied for the first time. Two novel poly(aryl ether)s containing azobenzene groups in the side chain were synthesized, and their photoinduced isomerization behavior and photoinduced deformation behavior were studied. It could be seen that the match of the excitation luminescence to the maximum absorption peak of the azobenzene groups was more compatible, and the photoinduced motion of the polymers was faster. In addition, poly(aryl ether)s containing azobenzene groups in the side chain showed highly stable photoinduced deformation. The results of this work will be helpful for designing polymers which could be controlled by lasers of different wavelengths.
研究领域:
材料科学
·
高分子化学
✓ 已验证
产品关联
DOI
PubMed
高影响因子
危险品化学品经营许可证（带存储）