Decorating of Ag and CuO on Cu Nanoparticles for Enhanced High Catalytic Activity to the Degradation of Organic Pollutants

Abstract

Metal/semiconductor composites are promising catalysts with superior catalytic activity. In this work, a Cu/CuO-Ag composite with structure that consisted of Ag and CuO nanoparticles (NPs) decorated on the surface of Cu were fabricated via a facile in situ method. With characterization by transmission electron microscopy (TEM), X-ray diffraction (XRD), X-ray photoelectron spectroscopy (XPS), energy dispersive X-ray spectroscopy (EDX), and inductively coupled plasma atomic emission spectrometry (ICP-AES), the structure and components of the Cu/CuO-Ag composite were well-defined. The Cu/CuO-Ag composite exhibited superior catalytic activities for the reduction of 4-nitrophenol (4-NP) in the presence of NaBH with just a trace amount of Ag NPs (1.28 wt %). The reduction reaction is completed in 75 s with an apparent rate constant k of 4.60 × 10 s. The Cu/CuO-Ag composite also showed excellent durable catalytic stability, as no significant activity loss was detected in the consecutive five reaction runs. With the aid of the Sabatier principle and volcano plot, the opportune chemical adsorption energy of the reagent 4-NP on the Cu/CuO-Ag composite was inferred to be the key to its high reaction rate. The CuO NPs as a semiconductor with narrow band gap also could help the Cu/CuO-Ag composite to capture the electrons/hydride ions and increase opportunities for 4-NP to be reduced. Furthermore, the Cu/CuO-Ag composite exhibited outstanding activity on the oxidative degradation of methylene blue (MB). This work enriched the bimetal/semiconductor catalyst system and supplied new insight into the catalysis mechanism.

In situ synthesis and properties of Ag NPs/carboxymethyl cellulose/starch composite films for antibacterial application

“…The Ag 3d characteristic peak consisted of a bimodal of Ag 3d 5/2 at 365 eV and Ag 3d 3/2 at 371 eV. The binding energy difference between the two characteristic peaks was 6 eV, which confirmed that the Ag element in as‐prepared ACS films existed in the form of elemental silver . The characteristic peaks of Ag 3d 5/2 and Ag 3d 3/2 of elemental silver were distributed at 368.3 and 374.3 eV, respectively .…”

Reduced graphene oxide decorated on Cu/CuO-Ag nanocomposite as a high-performance material for the construction of a non-enzymatic sensor: Application to the determination of carbaryl and fenamiphos pesticides

“…XRD patterns of Cu/CuO, Cu/ CuO-Ag and Cu/CuO-Ag/rGO composites were presented in Fig.1B. According to XRD patterns, Cu/CuO NPs have five diffraction peaks observed at 38°, 43°, 50°, 58°and 75°that indicating the presence of Cu and CuO without any other impurities [23]. In the spectrums of Cu/ CuO-Ag nanocomposite, the presence of Ag in the composition was showed with three peaks that show in the Fig.1B.…”

“…Composite of Cu/CuO-Ag was synthesized by the method similar to that previously reported [23,24] into the mix solution. Then, the products after 6 h reaction were collected and washed several times with water and ethanol and finally dried under vacuum.…”

CuO/Al₂O₃ Catalyst Preparation Conditions for Removal of Nitrobenzene by Heterogeneous Fenton-Like System

“…Regarding copper as a heterogeneous catalyst, catalytic performance is good and cost is low. A previous study found that γ-Cu/Al 2 O 3 has a good degradation effect on aromatic organic pollutants [12][13][14][15]. But it has been limited in water treatment processes due to the longer reaction time, the larger amount of copper dissolved and the H 2 O 2 .…”