Synthesis of silver nanoparticles on surface-functionalized multi-walled carbon nanotubes by ultraviolet initiated photo-reduction method

Roles of Oxygen Functional Groups in Carbon Nanotubes‐Supported Ag Catalysts for Electrochemical Conversion of CO2 to CO

“…Notably, Ag NPs on CNT−CO are observed with the widest size distribution, and their distribution is not as dense and uniform as that on CNT−COOH and CNT−OH, which means that there is relatively more exposed CNTs surface for Ag/CNT−CO. It can be reasonably speculated that the well dispersion of Ag NPs on CNT−COOH and CNT−OH is attributed to a large number of uniformly distributed surface acidic groups (carboxyl and hydroxyl groups), especially the carboxyl groups, which could serve as the anchoring sites for Ag precursors and facilitates the nucleation of Ag NPs . Similarly, the relatively less acidic groups result in an inferior ability of CNT−CO for loading Ag relative to CNT−COOH and CNT−CO.…”

“…In this work, three catalysts (Ag/CNT−COOH, Ag/CNT−OH and Ag/CNT−CO) were reasonably designed and fabricated by chemically loading Ag NPs on the oxygenic CNTs with precise tuning oxygen functional groups, and the roles of surface oxygen functional groups on CNTs in loading Ag NPs and electrochemical conversion of CO 2 to CO were comprehensively investigated. Specifically, on the nanoscale, Ag NPs loaded on CNT−COOH are observed with the most uniform size and dispersion due to the highest content of surface carboxyl groups, which have been proved to be the effective adsorption sites for the nucleation of Ag NPs . On the molecular level, the relatively lower p K a of carboxyl group endows it with the stronger ability of proton‐donation compared to hydroxyl and carbonyl groups, which may facilitate the formation of key intermediate (*COOH) on Ag/CNT−COOH when the rate‐limiting step for CO 2 ER is the proton‐electron coupling transfer (PECT) process .…”

Efficient Removal of Diclofenac from Aqueous Solution by Potassium Ferrate-Activated Porous Graphitic Biochar: Ambient Condition Influences and Adsorption Mechanism

“…Figure 5b shows the XPS spectrum of O 1 s for Fe@BC, where three peaks cantering at 531.4 eV, 532.5 eV, and 533.3 eV were clearly observed. The peak at 531.4 eV was attributed to signal of Fe-O (presence of lattice oxide oxygen in the oxides) [43], the peak at 532.5 eV suggested the presence of C=O, C-OH, or C-O-C groups [44], and the peak at 533.3 eV was attributed to oxygen in water molecules [45]. As shown in Figure 5c, C 1 s spectrum of the as-prepared sample shows five peaks, where the main sharp peak at 284.7 eV corresponded to C-C bonds with sp 3 hybridization [46], and other four peaks centered at 285.5, 287.7, 293.7, and 296.5 eV were attributed to C=N, C-O, C=O, O=C-O bonds, respectively [47,48].…”

Silver nanoparticles supported on carbon nanotube carpets: influence of surface functionalization

“…Similar observations were made [17,18] when CNT carpets were treated under dry and/or wet oxidizing chemistries prior to AgNP growth. Similarly, non-oxidative methods such as grafting certain polymeric groups [21][22][23] were also seen to increase the AgNP growth and subsequent antibacterial activity. The success of wettability alteration and durability resulting from each method should depend on interatomic bonds created between the graphitic nanotubes and surface functional groups, but is not clearly addressed in all cases.…”