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.
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http://dx.doi.org/10.1088/1361-6528/abdf90 | DOI Listing |
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 PDFAdv Mater
January 2025
Extreme Materials Research Center, Korea Institute of Science and Technology, 14-gil 5 Hwarang-ro, Seongbuk-gu, Seoul, 02792, Republic of Korea.
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 PDFAngew Chem Int Ed Engl
January 2025
South China University of Technology, School of Chemistry and Chemical Engineering, Wushan St., 510640, Guangzhou, CHINA.
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 PDFJ 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 PDFJ 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.
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