Structural Effects of Metal Single-Atom Catalysts for Enhanced Photocatalytic Degradation of Gemfibrozil

Abstract

The development of efficient catalysts is a highly necessary but challenging task within the field of environmental water remediation. Single-atom catalysts are promising nanomaterials within this respect, but in-depth studies encompassing this class of catalysts remain elusive. In this work, we systematically study the degradation of gemfibrozil, a persistent pollutant, on a series of carbon nitride photocatalysts, investigating both the effect of (i) catalyst textural properties and (ii) metal single atoms on the contaminant degradation. Tests in the absence of the catalyst result in negligible degradation rates, confirming the stability of the contaminant when dispersed in water. Then, photocatalytic tests at optimal pH, solvent, and wavelength reveal a correlation between the support surface area and the degradation. This points to the role of carbon nitride surface nanostructure on gemfibrozil degradation. In particular, the use of silver on mesoporous carbon nitride single-atom catalyst (Ag@mpgC3N4) leads to an unprecedented degradation of gemfibrozil (>90% within 60 min). The possible degradation intermediates and products were identified by mass spectrometry and were inert by cytotoxicity evaluation. We anticipate that, with further refinement and customization, the carbon nitride catalysts reported herein may find broad applications for light-driven degradation of other contaminants of emerging concern.

Nanostructured Carbon Nitride for Continuous-Flow Trifluoromethylation of (Hetero)arenes

“…The improved conversion of pyrrole and the subsequent enhanced yield for the catalytic product provided by the mpgC 3 N 4 catalyst could be easily justified with the increase of the surface area in this material, a key parameter in the light-catalyzed heterogeneous reaction, and considering that the optical properties in the three metal-free materials, i.e., band gap and charge separation, are unaffected by the change of the tridimensional structure. Particularly, the mesopores present in the mpgC 3 N 4 structures generates a tridimensional structure with enhanced surface area (>140 m 2 g –1 ) if compared with the 2D graphitic (5 m 2 g –1 ) and nanosheet (72 m 2 g –1 ) samples; this structural effect leads to an increased contact between light, catalyst, and reactant, which is beneficial for the reaction outcome . More detailed information regarding the formation of each side product in time is provided in the Supporting Information.…”

“…Particularly, the mesopores present in the mpgC 3 N 4 structures generates a tridimensional structure with enhanced surface area (>140 m 2 g –1 ) if compared with the 2D graphitic (5 m 2 g –1 ) and nanosheet (72 m 2 g –1 ) samples; this structural effect leads to an increased contact between light, catalyst, and reactant, which is beneficial for the reaction outcome. 60 More detailed information regarding the formation of each side product in time is provided in the Supporting Information .…”

Single-Atom Sn-Loaded Exfoliated Layered Titanate Revealing Enhanced Photocatalytic Activity in Hydrogen Generation

“…One of the critical challenges in single-atom catalysis is to stabilize the chemical state of the single atom on a semiconductor through the adjacent heteroatoms. Moreover, the single-atom oxidation state alteration is another challenge that is drastically impacted by the crystal structure and chemical composition of the surface of the semiconductor. − …”

“…Moreover, the single-atom oxidation state alteration is another challenge that is drastically impacted by the crystal structure and chemical composition of the surface of the semiconductor. 36 − 38 …”

Constructing Acrylate Copolymer Microspheres with Anisotropic Wrinkled Surface for Conjugating Antibacterial AgNPs

“…[21] As typical functional particles, silver nanoparticles (AgNPs) have been applied in many fields including biomedicae [22] and photocatalytic degradation. [23,24] Especially in the aspect of antibacterial applications, it has broad-spectrum antibacterial activities and good inhibitory effects on Gram-positive and Gram-negative bacteria, fungi, virus, and cancer cells, [25,26] as well as low cytotoxicity to mammalian cells. [27] The antibacterial mechanism was that Ag ions (Ag + ) could enter into the cell wall and attach to DNA, which leaded to the DNA alteration or these ions resist the respiratory chain of enzymes.…”