Hierarchical hollow nanostructured core@shell recyclable catalysts γ-Fe₂O₃@LDH@Au₂₅-x for highly efficient alcohol oxidation

Abstract

Magnetically recyclable 3D hierarchical hollow nanostructured Au25 nanocluster catalysts, assembled by an Au25Capt18 precursor method, exhibit an extraordinary catalytic performance for the aerobic oxidation of alcohol by molecular oxygen upon strong Au25NCs–LDH–magnetic core synergy.

γ‐Fe2O3@Cu3Al‐LDH‐TUD as a new Amphoteric, Highly Efficient and Recyclable Heterogeneous Catalyst for the Solvent‐free Synthesis of Dihydropyrano[3,2‐c]pyrazoles and dihydropyrano[3,2‐c]chromens

“…The γ‐Fe 2 O 3 @Cu 3 Al‐LDH nanoparticles were prepared following the previously reported procedure . Briefly, FeCl 2 .4H 2 O (0.318 g, 1.6 mmol) and FeCl 3 .6H 2 O (0.7568 g, 2.8 mmol) were dissolved in 320 ml deionized water (Fe +2 /Fe +3 ratio = 1/1.75) in a 500 ml round bottom flask and stirred with magnetic stirrer.…”

Discrimination of 1‐ and 2‐Propanol by Using the Transient Current Change of a Semiconducting ZnFe2O4 Chemiresistor

“…The changes in transient current of the ZnFe 2 O 4 chemiresistor are measured at different temperatures (260-320°C) for detecting equal concentrations (200 ppm) of the two structural isomers of propanol. [4][5][6][7][8][9]15] In the present work, we have studied the response of ZnFe 2 O 4 based SMO chemiresistor towards equal concentrations (200 ppm) of two isomeric VOCs namely 1-propanol and 2-propanol at four different operating temperatures (i. e. 260, 280, 300 and 320°C). First-principles calculations and kinetic studies on the interaction of 1-and 2propanol over ZnFe 2 O 4 provide further insight in support of the experimental evidence.…”

“…catalyzed aerobic oxidations of organic molecules are attractive as a cost-effective and greener route for the synthesis of fine chemicals as compared to the traditional liquid phase reactions. [4][5][6][7][8][9]15] In the present work, we have studied the response of ZnFe 2 O 4 based SMO chemiresistor towards equal concentrations (200 ppm) of two isomeric VOCs namely 1-propanol and 2-propanol at four different operating temperatures (i. e. 260, 280, 300 and 320°C). [7][8][9][10] Unlike physisorption based charge transfer sensors, semiconducting metal oxide (SMO) based chemiresistors are mostly operative at high temperature and their resistance/conductance changes in exposure to reducing gases or vapors.…”

“…[1][2][3][4][5][6] Several metal-oxides that are used as a catalyst for the aerobic oxidation of organic molecules are semiconductors (e. g. TiO 2 , ZnO, Fe 2 O 3 ) and also act as chemiresistors for the detection of vapor phase organic analytes. catalyzed aerobic oxidations of organic molecules are attractive as a cost-effective and greener route for the synthesis of fine chemicals as compared to the traditional liquid phase reactions.…”

“…[1][2][3][4][5][6] Several metal-oxides that are used as a catalyst for the aerobic oxidation of organic molecules are semiconductors (e. g. TiO 2 , ZnO, Fe 2 O 3 ) and also act as chemiresistors for the detection of vapor phase organic analytes. [4][5][6][7][8][9]15] In the present work, we have studied the response of ZnFe 2 O 4 based SMO chemiresistor towards equal concentrations (200 ppm) of two isomeric VOCs namely 1-propanol and 2-propanol at four different operating temperatures (i. e. 260, 280, 300 and 320°C). [11][12][13][14] Investigating the operation principle of SMO chemiresistors, it is identified that their transient current in response cycle is basically the reflection of collective interactions (e. g., adsorption, diffusion, and aerobic oxidation) of target analyte on the respective metal-oxide surface.…”