Sulphur vacancies-VS2@C3N4 drived by in situ supramolecular self-assembly for synergistic photocatalytic degradation of real wastewater and H2 production: Vacancies taming interfacial compact heterojunction and carriers transfer

A series of Bi2S3@ZIF-8 core–shell heterostructures has been synthesized using in situ self-assembly, which exhibit enhanced photocatalytic degradation of Rhodamine B under visible-light irradiation, reaching 25.3 times that observed for pristine Bi2S3 and 26.7 times that found for commercial Degussa P25.

Download Full-text

In vitro and in vivo polysaccharides assembly: ultrastructural and cytochemical study of growing plant cell wall components.

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s0424820100083035 ◽

1978 ◽

Vol 36 (2) ◽

pp. 434-435

Author(s):

D. Reis ◽

B. Vian ◽

J. C. Roland

Keyword(s):

Cell Wall ◽

Self Assembly ◽

Plant Cell Wall ◽

Higher Plants ◽

Three Dimensional ◽

Cytochemical Study ◽

Wall Components

Wall morphogenesis in higher plants is a problem still open to controversy. Until now the possibility of a transmembrane control and the involvement of microtubules were mostly envisaged. Self-assembly processes have been observed in the case of walls of Chlamydomonas and bacteria. Spontaneous gelling interactions between xanthan and galactomannan from Ceratonia have been analyzed very recently. The present work provides indications that some processes of spontaneous aggregation could occur in higher plants during the formation and expansion of cell wall.Observations were performed on hypocotyl of mung bean (Phaseolus aureus) for which growth characteristics and wall composition have been previously defined.In situ, the walls of actively growing cells (primary walls) show an ordered three-dimensional organization (fig. 1). The wall is typically polylamellate with multifibrillar layers alternately transverse and longitudinal. Between these layers intermediate strata exist in which the orientation of microfibrils progressively rotates. Thus a progressive change in the morphogenetic activity occurs.

Download Full-text

Probing the Dynamic Self-Assembly Behaviour of Photoswitchable Wormlike Micelles in Real Time

10.26434/chemrxiv.7098695 ◽

2018 ◽

Author(s):

Elaine A. Kelly ◽

Judith E. Houston ◽

Rachel Evans

Keyword(s):

Real Time ◽

Absorption Spectroscopy ◽

Self Assembly ◽

Uv Light ◽

Wormlike Micelles ◽

Tetraethylene Glycol ◽

Light Illumination ◽

First Time ◽

Dependent Processes

Understanding the dynamic self-assembly behaviour of azobenzene photosurfactants (AzoPS) is crucial to advance their use in controlled release applications such asdrug delivery and micellar catalysis. Currently, their behaviour in the equilibrium cis-and trans-photostationary states is more widely understood than during the photoisomerisation process itself. Here, we investigate the time-dependent self-assembly of the different photoisomers of a model neutral AzoPS, <a>tetraethylene glycol mono(4′,4-octyloxy,octyl-azobenzene) </a>(C8AzoOC8E4) using small-angle neutron scattering (SANS). We show that the incorporation of in-situUV-Vis absorption spectroscopy with SANS allows the scattering profile, and hence micelle shape, to be correlated with the extent of photoisomerisation in real-time. It was observed that C8AzoOC8E4could switch between wormlike micelles (transnative state) and fractal aggregates (under UV light), with changes in the self-assembled structure arising concurrently with changes in the absorption spectrum. Wormlike micelles could be recovered within 60 seconds of blue light illumination. To the best of our knowledge, this is the first time the degree of AzoPS photoisomerisation has been tracked in-situthrough combined UV-Vis absorption spectroscopy-SANS measurements. This technique could be widely used to gain mechanistic and kinetic insights into light-dependent processes that are reliant on self-assembly.

Download Full-text

In situ Time-Resolved Small-Angle X-ray Scattering Reveals the Formation Kinetics of Polyelectrolyte Complex Micelles

10.26434/chemrxiv.9876395.v1 ◽

2019 ◽

Author(s):

Hao Wu ◽

Jeffrey Ting ◽

Siqi Meng ◽

Matthew Tirrell

Keyword(s):

Small Angle ◽

Self Assembly ◽

Electrostatic Interactions ◽

Polyelectrolyte Complex ◽

Time Resolved ◽

X Ray ◽

X Ray Scattering ◽

Kinetics Of ◽

Ray Scattering

We have directly observed the in situ self-assembly kinetics of polyelectrolyte complex (PEC) micelles by synchrotron time-resolved small-angle X-ray scattering, equipped with a stopped-flow device that provides millisecond temporal resolution. This work has elucidated one general kinetic pathway for the process of PEC micelle formation, which provides useful physical insights for increasing our fundamental understanding of complexation and self-assembly dynamics driven by electrostatic interactions that occur on ultrafast timescales.

Download Full-text

An in situ diffuse reflectance FTIR investigation of photocatalytic degradation of 4-chlorophenol on a TiO2 powder surface

Chemical Physics Letters ◽

10.1016/0009-2614(93)85166-l ◽

1993 ◽

Vol 205 (1) ◽

pp. 55-61 ◽

Cited By ~ 118

Author(s):

Ulick Stafford ◽

Kimberly A. Gray ◽

Prashnat V. Kamat ◽

Arvind Varma

Keyword(s):

Photocatalytic Degradation ◽

Diffuse Reflectance ◽

Tio2 Powder ◽

Powder Surface ◽

Reflectance Ftir ◽

Ftir Investigation

Download Full-text

Development of In Situ Self-Assembly Nanoparticles to Encapsulate Lopinavir and Ritonavir for Long-Acting Subcutaneous Injection

Pharmaceutics ◽

10.3390/pharmaceutics13060904 ◽

2021 ◽

Vol 13 (6) ◽

pp. 904

Author(s):

Irin Tanaudommongkon ◽

Asama Tanaudommongkon ◽

Xiaowei Dong

Keyword(s):

Sustained Release ◽

Trough Concentration ◽

Self Assembly ◽

Subcutaneous Injection ◽

Drug Loading ◽

Entrapment Efficiency ◽

Long Acting

Most antiretroviral medications for human immunodeficiency virus treatment and prevention require high levels of patient adherence, such that medications need to be administered daily without missing doses. Here, a long-acting subcutaneous injection of lopinavir (LPV) in combination with ritonavir (RTV) using in situ self-assembly nanoparticles (ISNPs) was developed to potentially overcome adherence barriers. The ISNP approach can improve the pharmacokinetic profiles of the drugs. The ISNPs were characterized in terms of particle size, drug entrapment efficiency, drug loading, in vitro release study, and in vivo pharmacokinetic study. LPV/RTV ISNPs were 167.8 nm in size, with a polydispersity index of less than 0.35. The entrapment efficiency was over 98% for both LPV and RTV, with drug loadings of 25% LPV and 6.3% RTV. A slow release rate of LPV was observed at about 20% on day 5, followed by a sustained release beyond 14 days. RTV released faster than LPV in the first 5 days and slower than LPV thereafter. LPV trough concentration remained above 160 ng/mL and RTV trough concentration was above 50 ng/mL after 6 days with one subcutaneous injection. Overall, the ISNP-based LPV/RTV injection showed sustained release profiles in both in vitro and in vivo studies.

Download Full-text

Injectable Drug Delivery System Based on In Situ Self‐Assembly of Liquid Star Polyethylene Glycol–Poly(lactic‐ co ‐glycolic acid)

Advanced NanoBiomed Research ◽

10.1002/anbr.202170033 ◽

2021 ◽

Vol 1 (3) ◽

pp. 2170033

Author(s):

Bat-hen Eylon ◽

Alona Shagan ◽

Ayelet Shabtay-Orbach ◽

Adi Gross ◽

Boaz Mizrahi

Keyword(s):

Drug Delivery ◽

Polyethylene Glycol ◽

Drug Delivery System ◽

Delivery System ◽

Self Assembly ◽

Glycolic Acid ◽

Injectable Drug

Download Full-text

TiO2 Nanowires with Doped g-C3N4 Nanoparticles for Enhanced H2 Production and Photodegradation of Pollutants

Nanomaterials ◽

10.3390/nano11010254 ◽

2021 ◽

Vol 11 (1) ◽

pp. 254

Author(s):

Liushan Jiang ◽

Fanshan Zeng ◽

Rong Zhong ◽

Yu Xie ◽

Jianli Wang ◽

...

Keyword(s):

Environmental Governance ◽

Fossil Fuels ◽

H2 Production ◽

Tio2 Nanowires ◽

Photocatalytic Ability ◽

Production Of Hydrogen ◽

Growth Method ◽

Renewable Hydrogen ◽

Degradation Of Pollutants

With the rapid consumption of fossil fuels, along with the ever-increasing environmental pollution, it is becoming a top priority to explore efficient photocatalysts for the production of renewable hydrogen and degradation of pollutants. Here, we fabricated a composite of g-C3N4/TiO2 via an in situ growth method under the conditions of high-temperature calcination. In this method, TiO2 nanowires with a large specific surface area could provide enough space for loading more g-C3N4 nanoparticles to obtain C3N4/TiO2 composites. Of note, the g-C3N4/TiO2 composite could effectively photocatalyze both the degradation of several pollutants and production of hydrogen, both of which are essential for environmental governance. Combining multiple characterizations and experiments, we found that the heterojunction constructed by the TiO2 and g-C3N4 could increase the photocatalytic ability of materials by prompting the separation of photogenerated carriers. Furthermore, the photocatalytic mechanism of the g-C3N4/TiO2 composite was also clarified in detail.

Download Full-text

An In-Situ Reaction Route to Molecular Level Dispersed Bisimide and ZnO Nanorod Hybrids with Efficient Photo-Induced Charge Transfer

Nanoscale Research Letters ◽

10.1186/s11671-021-03504-3 ◽

2021 ◽

Vol 16 (1) ◽

Author(s):

Chunzheng Lv ◽

Lirong He ◽

Jiahong Tang ◽

Feng Yang ◽

Chuhong Zhang

Keyword(s):

Charge Transfer ◽

Electric Field ◽

Self Assembly ◽

Molecular Level ◽

Surface Photovoltage ◽

Zno Nanorod ◽

In Situ Reaction ◽

Perylene Bisimide ◽

Induced Charge

AbstractAs an important photoconductive hybrid material, perylene/ZnO has attracted tremendous attention for photovoltaic-related applications, but generally faces a great challenge to design molecular level dispersed perylenes/ZnO nanohybrids due to easy phase separation between perylenes and ZnO nanocrystals. In this work, we reported an in-situ reaction method to prepare molecular level dispersed H-aggregates of perylene bisimide/ZnO nanorod hybrids. Surface photovoltage and electric field-induced surface photovoltage spectrum show that the photovoltage intensities of nanorod hybrids increased dramatically for 100 times compared with that of pristine perylene bisimide. The enhancement of photovoltage intensities resulting from two aspects: (1) the photo-generated electrons transfer from perylene bisimide to ZnO nanorod due to the electric field formed on the interface of perylene bisimide/ZnO; (2) the H-aggregates of perylene bisimide in ZnO nanorod composites, which is beneficial for photo-generated charge separation and transportation. The introduction of ordered self-assembly thiol-functionalized perylene-3,4,9,10-tetracarboxylic diimide (T-PTCDI)/ ZnO nanorod composites induces a significant improvement in incident photo-to-electron conversion efficiency. This work provides a novel mentality to boost photo-induced charge transfer efficiency, which brings new inspiration for the preparation of the highly efficient solar cell.

Download Full-text