CdS nanocrystallites sensitized ZnO nanorods with plasmon enhanced photoelectrochemical performance

The Effects of Exposure Methods on the Toxicity of Zinc Oxide Nanoparticles

In recent years, with the widespread use of zinc oxide (ZnO) nanoparticles (NPs), more and more attentions are being given to its biological toxicity, the toxicity of ZnO NPs under different exposure methods is necessary to investigate. In this study, we prepared two ZnO dispersions with different particle sizes, namely small-size ZnO (S-ZnO) and Bigsize ZnO (B-ZnO), using polycarboxylic acid as dispersant. Mice were poisoned by intravenous injection and inhalation, respectively. The respiration coefficient, superoxide dismutase (SOD), Zn content in the organs of the mice were detected. It was discovered that ZnO NPs with smaller particle diameter can cause more serious toxicity in vivo after intravenous exposure and respiratory exposure. In addition, the mice showed symptoms of dyspnea after respiratory exposure and a massive number of fibroblasts were found in the alveolar structure of the lungs. In the intravenous injection group, the content of Zn in the liver and spleen of mice increased significantly, resulting in organ edema, and the organ coefficient of mice increased. Finally, the increase of GSH/GSSG indicated that cells were regulated under the antioxidant mechanism, which accelerated the removal of H2O2 from cells. In addition, the increase of GSH+GSSG content also indicated that ZnO NPs stimulated the creation of reactive oxygen species (ROS) in organs of experimental animals.

The investigation of CdS-quantum-dot-sensitized Ag-deposited TiO2 NRAs in photoelectrochemical hydrogen production

The synthesis of CdS/Ag/TiO2 for photoelectrochemical hydrogen production was carried out using electrochemical deposition and the SILAR method.

Challenges and prospects about the graphene role in the design of photoelectrodes for sunlight-driven water splitting

Graphene and its derivatives have emerged as potential materials for several technological applications including sunlight-driven water splitting reactions. This review critically addresses the latest achievements concerning the use of graphene as a player in the design of hybrid-photoelectrodes for photoelectrochemical cells. Insights about the charge carrier dynamics of graphene-based photocatalysts which include metal oxides and non-metal oxide semiconductors are also discussed. The concepts underpinning the continued progress in the field of graphene/photoelectrodes, including different graphene structures, architecture as well as the possible mechanisms for hydrogen and oxygen reactions are also presented. Despite several reports having demonstrated the potential of graphene-based photocatalysts, the achieved performance remains far from the targeted benchmark efficiency for commercial application. This review also highlights the challenges and opportunities related to graphene application in photoelectrochemical cells for future directions in the field.

A ClO-mediated photoelectrochemical filtration system for highly-efficient and complete ammonia conversion

The ability to convert excess ammonia in water into harmless N₂ is highly desirable for environmental remediation. We present a chlorine-oxygen radical (ClO)-mediated photoelectrochemical filtration system for highly efficient and complete ammonia removal from water. The customized photochemical device comprised a Ag-functionalized TiO₂nanotube array mesh photoanode and a Pd-Cu co-modified nickel foam (Pd-Cu/NF) cathode. Under illumination, holes generated at the anode catalyzed the conversion of H₂O and Cl^- to HOand Cl, respectively. In turn, these radicals then reacted further, yielding ClO, which selectively decomposed ammonia. The cathode enabled further reduction of anodic byproducts such as NO₃^- to N₂. The complete oxidation of all dissolved ammonia was achieved within 15 min reaction under neutral conditions, where N₂ was the dominant product. The impact of key parameters was assessed, which enabled the discovery of optimal reaction conditions and the proposal of the underlying working mechanism. The flow-through configuration demonstrated a 5-fold increase of ammonia oxidation rate compared to the conventional batch reactor. The role of ClO in the oxidation of ammonia was verified with electron paramagnetic resonance and scavenger studies. This study provided greater mechanistic insights into photoelectrochemical filtration technology and demonstrated the potential of future nanotechnology for removing ammonia.