Multifunctional long afterglow nanoparticles with enhanced photothermal effects for in vivo imaging and tumor-targeting therapy.

Considering the excellent properties such as deep tissue penetration, high signal-to-noise ratio, and in-situ recharge and reactivation, near-infrared luminescence long afterglow nanoparticles show considerable promise for biological application, especially in multifunctional imaging, targeting, and synergistic therapeutic. In this paper, Zn3Ga4GeO11: 0.1 % Cr3+, 1 % Yb3+, 0.1 % Tm3+@Ag-FA (ZGGO@Ag-FA, ZGA-FA) nanoparticles were synthesized by in-situ growth of Ag nanoparticles on the surface of long afterglow nanoparticles, and further modified with folic acid. Through precise adjustments, the luminescent properties of ZnGa2O4 were enhanced and notably boosted the photothermal effect of Ag by leveraging the upconversion emission of ZGGO, with a photothermal conversion efficiency reaching about 59.9 %. The ZGA-FA nanoparticles are ultra-small, measuring less than 50 nm. The modification with folic acid provides the ZGA-FA nanoparticles with excellent tumor-targeting capabilities, demonstrating effective enrichment and retention in tumor tissues, thus enabling long-term imaging and therapy through in vivo re-excitation. Due to its stable photothermal effect, outstanding near-infrared (NIR) afterglow imaging, and red-light charged characteristics, combined with effective tumor-targeting abilities, the therapeutic strategy proposed by this study has significant potential for clinical applications.

Facile synthesis of an ultrathin ZIF-67 layer on the surface of Sn/Ti co-doped hematite for efficient photoelectrochemical water oxidation.

Hematite is a promising photoanode for photoelectrochemical (PEC) water splitting but its practical performance has been severely hindered by its poor conductivity and sluggish water oxidation kinetics. Metal-organic frameworks (MOFs), considered as efficient oxygen evolution catalysts (OECs), have been widely applied for PEC water splitting in recent years. Here, we modified an ultrathin (about 2 nm) Co-based ZIF-67 layer on the surface of Sn/Ti co-doped α-Fe2O3 by a simple one-step solvothermal method. The resulting photoanode achieved a photocurrent density of 2 mA cm-2 at 1.23 VRHE, which was four-fold that of pristine Fe2O3. Detailed investigations manifest that Sn and Ti co-doping improves the conductivity of hematite, while ZIF-67 coating not only expands the optical-response range, but also accelerates the charge transfer at the semiconductor-electrolyte (S-E) interface to facilitate water oxidation kinetics. This work provides a method to design and study MOF overlayer decorating hematite photoanodes towards improving the PEC performance.