Tannin-based carbon xerogel as a promising co-catalyst for photodegradation processes based on solar light: a case study using the tin (IV) oxide/carbon xerogel composite

Covalent Triazine Frameworks (CTFs) are a class of Porous Organic Polymers which attracts continuously growing interest because of their outstanding chemical and physical properties. However, the control of extended porous organic frameworks’ structures at the molecular scale for a precise adjustment of their properties has hardly been achieved so far. Here, we present a series of bipyridine-based CTFs synthesized through polycondensation, in which the sequence of specific building blocks is well controlled. The reported synthetic strategy allows to tailor the physicochemical features of the CTF materials, including nitrogen content, apparent specific surface area and opto-electronic properties. Based on a comprehensive analytic investigation, we demonstrate a direct correlation of the CTF bipyridine content with the material features such as specific surface area, bandgap, charge separation and surface wettability with water. The entirety of those parameters dictates the catalytic activity as demonstrated for the photocatalytic hydrogen evolution reaction (HER). The material with the necessary balance between opto-electronic properties and highest hydrophilicity enables HER production rates of up to 7.2 mmol·h-1·g-1 under visible light irradiation and in the presence of a platinum co-catalyst.

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Electrochemical assessment of pigment-binding-pigment interactions in oil paint deterioration: a case study on indigo and Prussian blue

10.21203/rs.3.rs-23531/v1 ◽

2020 ◽

Author(s):

Antonio Doménech-Carbó ◽

María Teresa Doménech-Carbó ◽

Laura Osete-Cortina ◽

Margherita Donnici ◽

Nuria Guasch-Ferré ◽

...

Keyword(s):

Prussian Blue ◽

Uv Radiation ◽

Paint Film ◽

Solar Light ◽

Radical Scavenger ◽

Binding Media ◽

Synthetic Oil

Abstract The degradation of synthetic oil paint film specimens containing indigo and Prussian blue pigments and pictorial samples from the Sant Francesc de Paula painting from the museum of Cardedeu (Catalonia, Spain) has been studied by voltammetry of immobilized particles. This technique, combined with SEM-EDX, ATR-FTIR and CG-MS techniques permits to propose a dual scheme for the degradation of the pigments when submitted to natural, UV and UV solar light aging. Under ‘ordinary’ conditions, Prussian blue acts as a radical scavenger moderating the production of ROS produced in the binding media by the action of UV radiation, resulting in the formation of Berlin green and indigo adducts with radicals. In the case of localized areas of the Sant Francesc de Paula paint, strong degradation occurs where Prussian blue acts as a promoter of the indigo oxidation to isatin, thus resulting in a considerable chromatic shift.

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Engineering a highly dispersed co-catalyst on a few-layered catalyst for efficient photocatalytic H2 evolution: a case study of Ni(OH)2/HNb3O8 nanocomposites

Catalysis Science & Technology ◽

10.1039/c7cy01792h ◽

2017 ◽

Vol 7 (23) ◽

pp. 5662-5669 ◽

Cited By ~ 23

Author(s):

Yuzhou Xia ◽

Weihang Chen ◽

Shijing Liang ◽

Jinhong Bi ◽

Ling Wu ◽

...

Keyword(s):

Photocatalytic Activity ◽

H2 Evolution ◽

Co Catalyst ◽

Highly Dispersed ◽

Photocatalytic H2 Evolution ◽

Layered Catalyst

Ni(OH)2 has been highly dispersed on HNb3O8 nanosheets and the composites exhibited greatly enhanced photocatalytic activity.

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TiO2/Nb2O5/carbon xerogel ternary photocatalyst for efficient degradation of 4-chlorophenol under solar light irradiation

Ceramics International ◽

10.1016/j.ceramint.2020.02.249 ◽

2020 ◽

Vol 46 (10) ◽

pp. 14505-14515 ◽

Cited By ~ 1

Author(s):

Nicolas Perciani de Moraes ◽

Fernanda Azzoni Torezin ◽

Gustavo Viégas Jucá Dantas ◽

Juliana Giancoli Martins de Sousa ◽

Ricardo Bertholo Valim ◽

...

Keyword(s):

Light Irradiation ◽

Solar Light ◽

Carbon Xerogel ◽

Solar Light Irradiation

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Photocatalytic hydrogen evolution using nanocrystalline gallium oxynitride spinel

Journal of Materials Chemistry A ◽

10.1039/c4ta03676j ◽

2014 ◽

Vol 2 (45) ◽

pp. 19247-19252 ◽

Cited By ~ 12

Author(s):

H. A. Naveen Dharmagunawardhane ◽

William R. Woerner ◽

Quiyan Wu ◽

Huafeng Huang ◽

Xianyin Chen ◽

...

Keyword(s):

Hydrogen Evolution ◽

Light Irradiation ◽

Solar Light ◽

Catalyst Loading ◽

Co Catalyst ◽

Photocatalytic Hydrogen Evolution ◽

Simulated Solar Light ◽

Solar Light Irradiation

Photocatalytic hydrogen evolution from water was observed over nanocrystalline gallium oxynitride spinel under simulated solar light irradiation (320 nm <λ< 800 nm). Up to 8 μmol h−1of H2was evolved without co-catalyst loading.

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