Search

Series of Er3+/Yb3+/Fe3+-tridoped NaBiF 4 nanoparticles were synthesized through a simple precipitation reaction method at room temperature. The effect of the Fe3+ ions on the microstructure and upconversion (UC) luminescence properties of the developed samples were studied in detail. Through the Fe3+ ions doping engineering, the enhancement in both green and red UC emission intensities were observed and the optimal doping concentration for Fe3+ ions was revealed to be 30 mol%. Owing to the fluorescence intensity ratio technology, the optical thermometric performances of the resultant products in the temperature range of 303–543 K were investigated and the maximum sensor sensitivity of the studied nanoparticles was 0.0053 K−1 at 543 K. Moreover, the internal heating behaviors of the obtained nanoparticles were investigated and the product temperature was improved to 399 K when the pump power was set at 260 mW. Our systematic and complementary studies suggested that the Er3+/Yb3+/Fe3+-tridoped NaBiF 4 nanoparticles with splendid UC behaviors were poised as next-generation promising candidates for nanothermometer and optical heaters. • The Er3+/Yb3+/Fe3+-tridoped NaBiF 4 nanoparticles were successfully prepared at room temperature. • With introducing of Fe3+, both microstructure and UC emission performance of studied samples were tailored. • The maximum sensor sensitivity of the synthesized nanoparticles as high as 0.0053 K−1 at 543 K. • The prepared nanoparticles can convert the excitation light source into heat. [ABSTRACT FROM AUTHOR]

• Pt nanoparticles embedded at the interface between CdS and NaNbO 3. • 18%CdS/2%Pt/N-NaNbO 3 nanorods shows the highest activity of 14,218 μmol⋅ g−1⋅ h−1. • The unique Z-scheme charge transfer mechanism is proposed. • The Pt nanoparticle bridge plays the important role. The development of heterojunction photocatalysts is still limited by poor interfacial charge carriers separation efficiency. In this work, we have successfully designed CdS/Pt/N-NaNbO 3 multilayer bridged nanostructure by embedding of Pt nanoparticles (NPs) into the interface between CdS quantum dots (CdS QDs) and perovskite N-doped NaNbO 3. The Pt NPs not only play the role of bonding CdS QDs and NaNbO 3 , but also provide a motive force for the charge carriers transfer and enormously shorten the migration path. Apart from the efficient Z-scheme charge transmission path of the CdS/Pt/N-NaNbO 3 nanorods, strong visible light absorption (400−800 nm) can also be tailored by N doping and introducing of Pt NPs, CdS QDs, demonstrated by the UV–vis. DRS measurement. As expected, the photocatalytic hydrogen evolution rate of 18 %CdS/2%Pt/N-NaNbO 3 nanorods is 134 and 28 times higher than that of bare NaNbO 3 nanorods and CdS QDs, respectively, under visible light (λ > 420 nm). This is the highest value so far reported among the NaNbO 3 -based photocatalysts. This study has important implications for photocatalytic hydrogen evolution and novel fabrication of NaNbO 3 -based materials. [ABSTRACT FROM AUTHOR]

Bacterial biofilms pose a serious threat to human health, as they prevent the penetration of antimicrobial agents. Developing nanocarriers that can simultaneously permeate biofilms and deliver antibacterial agents is an attractive means of treating bacterial biofilm infections. Herein, photosensitive metal–organic framework (MOF) nanoparticles were developed to promote the penetration of antibiotics into biofilms, thereby achieving the goal of eradicating bacterial biofilms through synergistic photodynamic and antibiotic therapy. First, a ligand containing benzoselenadiazole was synthesized and incorporated into MOF skeletons to construct benzoselenadiazole-doped MOFs (Se-MOFs). The growth of the Se-MOFs could be regulated to obtain nanoparticles (Se-NPs) in the presence of benzoic acid. The singlet oxygen (1O2) generation efficiencies of the Se-MOFs and Se-NPs were evaluated. The results show that the Se-NPs exhibited a higher 1O2 generation efficacy than the Se-MOF under visible-light irradiation because the small size of the Se-NPs was conducive to the diffusion of 1O2. Afterward, an antibiotic drug, polymyxin B (PMB), was conjugated onto the surface of the Se-NPs via amidation to yield PMB-modified Se-NPs (PMB-Se-NPs). PMB-Se-NPs exhibit a synergistic antibacterial effect by specifically targeting the lipopolysaccharides present in the outer membranes of Gram-negative bacteria through surface-modified PMB. Benefiting from the synergistic therapeutic effects of antibiotic and photodynamic therapy, PMB-Se-NPs can efficiently eradicate bacterial biofilms at relatively low antibiotic doses and light intensities, providing a promising nanocomposite for combating biofilm infections. [ABSTRACT FROM AUTHOR]