The in situ etching assisted synthesis of Pt–Fe–Mn ternary alloys with high-index facets as efficient catalysts for electro-oxidation reactions

Small particles of a low-melting phase embedded in a solid matrix with a higher melting point offer the possibility of studying the mechanisms of melting and solidification directly by in-situ observation in a transmission electron microscope. Previous studies of Pb, Cd and other low-melting inclusions embedded in an Al matrix have shown well-defined orientation relationships, strongly faceted shapes, and an unusual size-dependent superheating before melting.[e.g. 1,2].In the present study we have examined the shapes and thermal behavior of eutectic Pb-Cd inclusions in Al. Pb and Cd form a simple eutectic system with each other, but both elements are insoluble in solid Al. Ternary alloys of Al (Pb,Cd) were prepared from high purity elements by melt spinning or by sequential ion implantation of the two alloying additions to achieve a total alloying addition of up to lat%. TEM observations were made using a heating stage in a 200kV electron microscope equipped with a video system for recording dynamic behavior.

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MOF-derived M-OOH with rich oxygen defects by in-situ electro-oxidation reconstitution for highly efficient oxygen evolution reaction

Journal of Materials Chemistry A ◽

10.1039/d1ta01638e ◽

2021 ◽

Author(s):

Zhikai Shi ◽

Zebin Yu ◽

Ronghua Jiang ◽

Jun Huang ◽

Yanping Hou ◽

...

Keyword(s):

Oxygen Evolution ◽

Oxygen Evolution Reaction ◽

Energy Production ◽

Low Cost ◽

Highly Efficient ◽

Oxygen Defects ◽

Electro Oxidation

The oxygen evolution reaction (OER) is an important half-reaction in the field of energy production. However, how effectively, simply, and greenly to prepare low-cost OER electrocatalysts remains a problem. Herein,...

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Carbon Nitride Quantum Dots Modified TiO2 Inverse Opal Photonic Crystal for Solving Indoor VOCs Pollution

Catalysts ◽

10.3390/catal11040464 ◽

2021 ◽

Vol 11 (4) ◽

pp. 464

Author(s):

Jie Yu ◽

Angel Caravaca ◽

Chantal Guillard ◽

Philippe Vernoux ◽

Liang Zhou ◽

...

Keyword(s):

Quantum Dots ◽

Carbon Nitride ◽

Sol Gel ◽

Green Energy ◽

Inverse Opal ◽

Oxidation Reactions ◽

Composite Photocatalyst ◽

Colloidal Photonic Crystals ◽

Inverse Opal Structure

Indoor toxic volatile organic compounds (VOCs) pollution is a serious threat to people’s health and toluene is a typical representative. In this study, we developed a composite photocatalyst of carbon nitride quantum dots (CNQDs) in situ-doped TiO2 inverse opal TiO2 IO for efficient degradation of toluene. The catalyst was fabricated using a sol-gel method with colloidal photonic crystals as the template. The as-prepared catalyst exhibited excellent photocatalytic performance for degradation of toluene. After 6 h of simulated sunlight irradiation, 93% of toluene can be converted into non-toxic products CO2 and H2O, while only 37% of toluene is degraded over commercial P25 in the same condition. This greatly enhanced photocatalytic activity results from two aspects: (i) the inverse opal structure enhances the light harvesting while providing adequate surface area for effective oxidation reactions; (ii) the incorporation of CNQDs in the framework of TiO2 increases visible light absorption and promotes the separation of photo-generated charges. Collectively, highly efficient photocatalytic degradation of toluene has been achieved. In addition, it can be expanded to efficient degradation of organic pollutants in liquid phase such as phenol and Rhodamine B. This study provides a green, energy saving solution for indoor toxic VOCs removal as well as for the treatment of organic wastewater.

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