scholarly journals Visible-Light-Mediated Amination of π-Nucleophiles with N-Aminopyridinium Salts

2019 ◽  
Author(s):  
Katarzyna Goliszewska ◽  
Katarzyna Rybicka-Jasińska ◽  
Jakub Szurmak ◽  
Dorota Gryko
Keyword(s):  
Visible Light ◽  
Carbonyl Compounds ◽  
Uv Light ◽  
Light Irradiation ◽  
Pyridinium Salts ◽  
Nitrenium Ions ◽  
Uv Light Irradiation

Under UV light irradiation <i>N</i>,<i>N</i>-(diphenylamino)pyridinium salts generate nitrenium ions. Herein, we report that in the presence of a photoredox catalyst nitrogen-centered radicals form which then react with enol equivalents to give amino carbonyl compounds in excellent yields.<br>

scholarly journals Visible-Light-Mediated Amination of π-Nucleophiles with N-Aminopyridinium Salts

2019 ◽  
Author(s):  
Katarzyna Goliszewska ◽  
Katarzyna Rybicka-Jasińska ◽  
Jakub Szurmak ◽  
Dorota Gryko
Keyword(s):  
Visible Light ◽  
Carbonyl Compounds ◽  
Uv Light ◽  
Light Irradiation ◽  
Pyridinium Salts ◽  
Nitrenium Ions ◽  
Uv Light Irradiation

Under UV light irradiation <i>N</i>,<i>N</i>-(diphenylamino)pyridinium salts generate nitrenium ions. Herein, we report that in the presence of a photoredox catalyst nitrogen-centered radicals form which then react with enol equivalents to give amino carbonyl compounds in excellent yields.<br>

scholarly journals Degradation of Paracetamol by Photolysis Using C-N-codoped TiO2

Molekul ◽  
2017 ◽  
Vol 12 (2) ◽  
pp. 189
Author(s):  
Vanny Yulia Safitri ◽  
Adlis Santoni ◽  
Diana Vanda Wellia ◽  
Khoiriah Khoiriah ◽  
Safni Safni
Keyword(s):  
Water Pollution ◽  
Visible Light ◽  
Uv Light ◽  
Light Irradiation ◽  
Solar Light ◽  
Tio2 Catalyst ◽  
Codoped Tio2 ◽  
Uv Light Irradiation ◽  
Optimum Weight ◽  
Visible Light Degradation

Paracetamol is generally used as analgesic and antipyretic drugs. Contamination paracetamol in the environment can occur because of waste material disposal from production site and immediate disposal of household that cause water pollution. Paracetamol is degraded by photolysis method under irradiation 10 watt UV-light (λ=365 nm), visible-light (Philips LED 13 watt 1400 lux) and solar-light with and without addition C-N-codoped TiO2catalyst. The solution is analyzed by UV-Vis spectrophotometer at λ 200-400 nm. Optimum weight of C-N-codoped TiO2 catalyst obtained is 20 mg under UV-light photolysis. Paracetamol 4 mg/L is degraded 45.48% after 120 minutes under UV-light irradiation without catalyst, and increases to be 69.31% by using 20 mg catalyst. While degradation percentage of paracetamol is 16.96 % without catalyst, the percentage increases to be 34.29% after using 20 mg catalyst for 120 minutes photolysis under visible-light. Degradation of paracetamol by solar light achieves only 12.27% in absance of catalyst for 120 minutes irradiation, but it increases significantly until 70.39% in presence of 20 mg catalyst.

Construction of ZnxCd1−xS/CeO2 composites for enhanced photocatalytic activity and stability by chemical precipitation method

2021 ◽  
pp. 2150334
Author(s):  
Yi-Feng Chai ◽  
Zhong-Hua Zhu ◽  
Ming-Wei Liu ◽  
Jing Zeng ◽  
Gui-Fang Huang ◽  
...  
Keyword(s):  
Photocatalytic Activity ◽  
Methyl Orange ◽  
Visible Light ◽  
Visible Light Irradiation ◽  
Uv Light ◽  
Chemical Precipitation ◽  
Charge Carriers ◽  
Light Irradiation ◽  
Precipitation Method ◽  
Uv Light Irradiation

Development photoinduced photocatalysts is a significant approach to improve photocatalytic activity and stability. Herein, we successfully prepared Zn[Formula: see text]Cd[Formula: see text]S/CeO2 composites by a facile method. It is found that the Zn[Formula: see text]Cd[Formula: see text]S/CeO2 composites show significant enhancement in photocatalytic activity for methyl orange (MO) degradation under visible and UV light irradiation. The degradation efficiency reaches up to 3.7 times higher than that of pure CeO2 under visible light irradiation. Moreover, the Zn[Formula: see text]Cd[Formula: see text]S/CeO2 samples have almost no loss of photocatalytic activity after five recycles, indicating good photocatalytic stability of the samples. The attractive photocatalytic activity of the Zn[Formula: see text]Cd[Formula: see text]S/CeO2 samples could be attributed to the robust charge carriers transfer and separation.

Photocatalytic Degradation of Carbaryl over Novel MWNT-TiO2 Nanocomposite under Visible Light Irradiation

2011 ◽  
Vol 233-235 ◽  
pp. 476-480
Author(s):  
Ke Dai ◽  
Hai Bo Chen ◽  
Xu Li ◽  
Hao Chen ◽  
Qiao Yun Huang
Keyword(s):  
Visible Light ◽  
Visible Light Irradiation ◽  
Ring Opening ◽  
Uv Light ◽  
Light Irradiation ◽  
Photodegradation Efficiency ◽  
Uv Light Irradiation ◽  
Ring Opening Reaction ◽  
Visible Light Driven ◽  
Direct Growth

The MWNT-TiO2nanocomposite was synthesized via direct growth of TiO2nanoparticles on the surface of the functionalized MWNTs by the hydrothermal treatment and utilized as the photocatalyst in the carbaryl degradation under both visible light and UV light irradiation. Visible-light-driven activity and enhanced UV-light-driven activity are both achieved as the composite MWNTs with TiO2can efficiently enhance the light absorption and charge separation and then photocatalytic activity. The photodegradation efficiency of carbaryl was examined by HPLC and IC techniques, which demonstrates that carbaryl can be readily degraded under visible light irradiation. Based on the obtained experimental results, assisted with the computer simulation of carbaryl molecule on PM3 level, it is presumed that the degradation of carbaryl starts with the break of N21-C23 and C19-N21 bonds and ends in the generation of naphthalen-1-ol before the ring-opening reaction.

scholarly journals Photocatalytic activity under visible light irradiation of cement based materials containing TiO2-xNy nanoparticles

2019 ◽  
pp. 87-96
Author(s):  
Ludovic I. Dorkis ◽  
Juan David Cohen ◽  
Jorge I. Tobón
Keyword(s):  
Visible Light ◽  
Rhodamine B ◽  
Uv Light ◽  
Light Irradiation ◽  
Efficiency Coefficient ◽  
Photocatalytic Efficiency ◽  
X Ray Diffraction ◽  
Cement Pastes ◽  
Uv Light Irradiation ◽  
Munk Function

Self-cleaning activity of Portland cement pastes blended with nanoparticles of titanium oxynitride (TiO2−xNy) was studied. Samples with various amounts of TiO2−xNy (1% and 3%) were evaluated under irradiation of UV and visible light, and with two curing ages (65 hour and 28 days). Rhodamine B was the pigment used and its loss of color on the cement pastes was carried out using a Spectrometer UV/Vis measuring the coordinates CIE (Commission Internationale de l’Eclairage) L∗, a∗, b∗. Discoloration of Rhodamine B on the surface of the samples was established as the photocatalytic efficiency coefficient (ε). In addition, samples with TiO2 nanoparticles (1% and 3%) were studied under the same conditions and their performances were compared with TiO2-xNy. The presence of nitrogen in the tetragonal structure of TiO2 was evidenced by X-ray diffraction (XRD), ultraviolet-visible diffuse reflectance spectrophotometry and Carbon, Hydrogen and Nitrogen (CHN) analysis. The band gap for TiO2 and TiO2-xNy was determined by the transformed Kubelka-Munk function ( [F (R∞) hv]1/2). The results have shown a similar behavior for both additions under UV light irradiation, with 3% being the addition with the highest photocatalytic efficiency obtained in the early ages of curing time.  TiO2−xNy showed activity under irradiation with visible light, unlike TiO2, which could only be activated under UV light.  At the late curing ages, the samples with 3% of TiO2-xNy showed the highest efficiency under irradiation of UV and visible light.

Retracted Article: Synthesis of Fe3+-incorporated open-framework gallium borate catalyst for photocatalytic CO2 reduction driven by visible light irradiation

2018 ◽  
Author(s):  
Qiaoqi Li ◽  
Lili Zhang ◽  
Pu Su Zhao ◽  
Jingzhou Yin ◽  
Jun Xia ◽  
...  
Keyword(s):  
Visible Light ◽  
Water Splitting ◽  
Visible Light Irradiation ◽  
Uv Light ◽  
Co2 Reduction ◽  
Light Irradiation ◽  
Relevant Study ◽  
Open Framework ◽  
Uv Light Irradiation ◽  
Retracted Article

Gallium borates semiconductors have been developed as effective photocatalysts for water splitting driven by UV light irradiation, but there is no relevant study for the CO2 photoreduction application. Herein, we...

scholarly journals Novel TiO2/GO/CuFe2O4 nanocomposite: a magnetic, reusable and visible-light-driven photocatalyst for efficient photocatalytic removal of chlorinated pesticides from wastewater

RSC Advances ◽  
2020 ◽  
Vol 10 (57) ◽  
pp. 34806-34814 ◽  
Author(s):  
A. M. Ismael ◽  
A. N. El-Shazly ◽  
S. E. Gaber ◽  
M. M. Rashad ◽  
A. H. Kamel ◽  
...  
Keyword(s):  
Visible Light ◽  
Photocatalytic Degradation ◽  
Ball Milling ◽  
Uv Light ◽  
Low Cost ◽  
Light Irradiation ◽  
Chlorinated Pesticides ◽  
Uv Light Irradiation ◽  
Photocatalytic Removal ◽  
Visible Light Driven

A TiO2/GO/CuFe2O4 heterostructure photocatalyst is fabricated by a simple and low cost ball milling pathway for enhancing the photocatalytic degradation of chlorinated pesticides under UV light irradiation.

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