Dual-mode catalytic degradation of diclofenac by copper oxide-modified TiO2/MnOx composites: insights from dark and UV-A activation

Result code in IS VaVaI

<a href="https://www.isvavai.cz/riv?ss=detail&h=RIV%2F61388980%3A_____%2F25%3A00636947" target="_blank" >RIV/61388980:_____/25:00636947 - isvavai.cz</a>

Alternative codes found

RIV/44555601:13440/25:43899158 RIV/44555601:13520/25:43899158 RIV/61989592:15640/25:73631910 RIV/61989100:27640/25:10258736

Result on the web

<a href="https://hdl.handle.net/11104/0368580" target="_blank" >https://hdl.handle.net/11104/0368580</a>

DOI - Digital Object Identifier

<a href="http://dx.doi.org/10.1039/d4cy01400f" target="_blank" >10.1039/d4cy01400f</a>

Result language

angličtina

Original language name

Dual-mode catalytic degradation of diclofenac by copper oxide-modified TiO2/MnOx composites: insights from dark and UV-A activation

Original language description

Diclofenac sodium (DCF), a widely used nonsteroidal anti-inflammatory drug, is a persistent pharmaceutical contaminant that resists removal by conventional wastewater treatment. In this study, CuO-modified TiO2/MnOx composites were developed as multifunctional catalysts for DCF degradation under both dark and UV-A conditions. The materials exhibited dual-mode reactivity through distinct mechanisms: (i) non-radical oxidative degradation under dark conditions, and (ii) radical-mediated photocatalysis under UV-A irradiation. Under illumination, the formation of an interfacial p-n-p heterojunction between CuO, MnOx, and TiO2 generated internal electric fields that directed charge carrier migration-electrons flowing from the conduction band of TiO2 toward CuO and MnOx domains, and holes in the reverse direction. This spatial charge separation suppressed recombination and sustained redox cycling between Cu2+/Cu+ and Mn4+/Mn3+, promoting continuous ROS generation. In the absence of light, DCF degradation proceeded via non-radical oxidative pathways involving surface-bound reactive oxygen species and redox-active metal centers. Surface-sensitive XPS and hydroxyl quantification (TOTH) revealed elevated Mn3+/Mn4+ ratios, enriched surface-associated lattice oxygen, and highOH group densities for the most active catalysts. These features collectively facilitated pollutant adsorption, oxygen activation, and sustained interfacial electron transfer. LC-MS/MS analysis confirmed a consistent degradation pathway across both regimes, involving hydroxylation, decarboxylation, and dechlorination of DCF. The Cu/5Ti5Mn-HT and Cu/8Ti2Mn-HT catalysts achieved exceptional dark-phase degradation efficiencies (similar to 99.8% and similar to 99.4%, respectively), while Cu/TiO2 exhibited the highest UV-A photocatalytic performance (similar to 42%). These findings demonstrate the synergistic advantage of redox-active metal oxides and interfacial design, establishing CuO-MnOx-TiO2 composites as promising candidates for advanced pharmaceutical pollutant remediation.

Czech name

—

Czech description

—

Type

J_imp - Article in a specialist periodical, which is included in the Web of Science database

CEP classification

—

OECD FORD branch

10402 - Inorganic and nuclear chemistry

Project

<a href="/en/project/LM2023066" target="_blank" >LM2023066: Nanomaterials and Nanotechnologies for Environment Protection and Sustainable Future</a><br>

Continuities

I - Institucionalni podpora na dlouhodoby koncepcni rozvoj vyzkumne organizace

Publication year

2025

Confidentiality

S - Úplné a pravdivé údaje o projektu nepodléhají ochraně podle zvláštních právních předpisů

Name of the periodical

Catalysis Science &Technology

ISSN

2044-4753

e-ISSN

2044-4761

Volume of the periodical

15

Issue of the periodical within the volume

15

Country of publishing house

GB - UNITED KINGDOM

Number of pages

19

Pages from-to

4438-4456

UT code for WoS article

001508894400001

EID of the result in the Scopus database

2-s2.0-105008730851