Optimal rare-earth (La, Y and Sm) doping conditions and enhanced mechanism for photocatalytic application of ceria nanorods.

Nanotechnology

Department of Metallurgical Engineering, College of Materials and Metallurgy, Guizhou University, Huaxi, Guiyang, Guizhou, 550025, People's Republic of China. Guizhou Province Key Laboratory of Metallurgical Engineering and Process Energy Saving, Guiyang, Guizhou, 550025, People's Republic of China.

Published: February 2021

Morphological tuning or additional cation doping is one of the potential and simple methods to enhance the photocatalytic properties of ceria, in which rare-earth element doped ceria nanorods (CeO-RE NRs) are expected to be a promising photocatalyst with high activity. But the optimal doping conditions, including the variety and concentration of RE elements are ambiguous, and the contribution of doped RE ions to the enhancement of photocatalytic activity needs to be further studied. In this work, we doped La, Y and Sm with a wide range of 0%-30% into CeO NRs, and investigated the phase, morphology, band gap, oxygen vacancy concentration, PL spectra and photocatalytic activity variation under different doping conditions. All synthesized CeO-RE NRs possessed a good nanorod morphology except the 15 and 30% Y-doped samples. The energy band gaps of the synthesized samples changed slightly; the 10% CeO-RE NRs with the narrowest band gaps possessed the higher photocatalytic performance. The most outstanding photocatalyst was found to be the 10% Y-doped CeO NRs with a methylene blue photodegradation ratio of 85.59% and rate constant of 0.0134 min, which is particularly associated with a significant higher oxygen vacancy concentration and obviously lower recombination rate of photogenerated e/h pairs. The doped RE ions and the promotion of oxygen vacancy generation impede the recombination of photogenerated carriers, which is proposed as the main reason to enhance the photocatalytic property of CeO.

Download full-text PDF

Source
http://dx.doi.org/10.1088/1361-6528/abdf90DOI Listing

Publication Analysis

Top Keywords

doping conditions
12
ceo-re nrs
12
oxygen vacancy
12
ceria nanorods
8
enhance photocatalytic
8
doped ions
8
photocatalytic activity
8
ceo nrs
8
vacancy concentration
8
band gaps
8

Similar Publications

Surface Oxygen Vacancies on Copper-Doped Titanium Dioxide for Photocatalytic Nitrate-to-Ammonia Reduction.

J Am Chem Soc

January 2025

Research Center for Solar Energy Chemistry and Division of Chemical Engineering, Graduate School of Engineering Science, Osaka University, Toyonaka 560-8531, Japan.

Photocatalytic transformation of nitrate (NO) in wastewater into ammonia (NH) is a challenge in the detoxification and recycling of limited nitrogen resources. In particular, previously reported photocatalysts cannot promote the reaction using water as an electron donor. Herein, we report that copper-doped titanium dioxide (Cu-TiO) powders, prepared via the sol-gel method and subsequent calcination, promote NO-to-NH reduction in water.

View Article and Find Full Text PDF

Hydrogen peroxide (HO) electrosynthesis via the 2e oxygen reduction reaction (ORR) is considered as a cost-effective and safe alternative to the energy-intensive anthraquinone process. However, in more practical environments, namely, the use of neutral media and air-fed cathode environments, slow ORR kinetics and insufficient oxygen supply pose significant challenges to efficient HO production at high current densities. In this work, mesoporous B-doped carbons with novel curved BC active sites, synthesized via a carbon dioxide (CO) reduction using a pore-former agent, to simultaneously achieve excellent 2e ORR activity and improved mass transfer properties are introduced.

View Article and Find Full Text PDF

An inevitable overoxidation process is considered as one of the most challenging problems in the direct conversion of methane (CH4) to methanol (CH3OH), which is limited by the uncontrollable cracking of key intermediates. Herein, we have successfully constructed a photocatalyst, the Fe-doped ZnO hollow polyhedron (Fe/ZnOHP), for the highly selective photoconversion of CH4 to CH3OH under mild conditions. In-situ experiments and density functional theory calculations confirmed that the introduction of Fe was able to decrease the energy level of the O 2p orbital, which passivated the activity of lattice oxygen in ZnO nanocrystals.

View Article and Find Full Text PDF

Interfacial mechanisms of enhanced photoluminescence in AgI-doped red light emitting perovskite quantum dot glass.

J Colloid Interface Sci

January 2025

Institute of Optoelectronic Materials and Devices, College of Optical and Electronic Technology, China Jiliang University, Hangzhou 310018 PR China. Electronic address:

Red light emitting perovskite quantum dot (PQD) glass, with narrow-band emission and excellent stability, holds great potential for applications in liquid crystal displays. However, its low photoluminescence quantum yield (PLQY) remains the biggest obstacle limiting its practical application. Additionally, the mechanism behind the enhancement of the PLQY is not well understood, which restricts the further improvement of the PLQY in red light emitting PQD glass.

View Article and Find Full Text PDF

Revealing the Potential-Dependent Rate-Determining Step of Oxygen Reduction Reaction on Single-Atom Catalysts.

J Am Chem Soc

January 2025

Department of Chemistry and Guangdong Provincial Key Laboratory of Catalysis, Southern University of Science and Technology, Shenzhen 518055, Guangdong, China.

Single-atom catalysts (SACs) have attracted widespread attention due to their potential to replace platinum-based catalysts in achieving efficient oxygen reduction reaction (ORR), yet the rational optimization of SACs remains challenging due to their elusive reaction mechanisms. Herein, by employing ab initio molecular dynamics simulations and a thermodynamic integration method, we have constructed the potential-dependent free energetics of ORR on a single iron atom catalyst dispersed on nitrogen-doped graphene (Fe-N/C) and further integrated these parameters into a microkinetic model. We demonstrate that the rate-determining step (RDS) of the ORR on SACs is potential-dependent rather than invariant within the operative potential range.

View Article and Find Full Text PDF

Want AI Summaries of new PubMed Abstracts delivered to your In-box?

Enter search terms and have AI summaries delivered each week - change queries or unsubscribe any time!