Photo-induced charge transfer in Prussian blue analogues as detected by photoacoustic spectroscopy

Enhanced removal of trace thallium by photo-promoted adsorption using Prussian blue@filter papers: Performance and mechanistic insights

Developing highly efficient adsorbents for the removal of trace thallium(I) (Tl+) is crucial for addressing environmental challenges. In this study, we successfully synthesized cubic Prussian blue (PB) loading on filter papers using an intermediate layer (dopamine/polyethyleneimine) via in-situ methods. The as-prepared PB-modified FP demonstrated outstanding anti-interference properties and light-enhanced adsorption performance for Tl+ (0.5 mg/L) under ultraviolet (UV) irradiation, exhibiting twice the effectiveness compared to dark conditions, even in acidic and coexisting ionic environments. This indicated its suitability for treating complex Tl+-contaminated water. Notably, the removal efficiency for trace Tl+ was almost 100%, with a maximum experimental adsorption capacity of 86.2 mg/g after 1-h photo-promoted adsorption under 365 nm UV. Characterization results supported a proposed photo-driven redox mechanism that elucidated the interaction between Tl+ and PB-modified FP. Specifically, the accelerated Fe(III) to Fe(II) redox reaction facilitated Tl+ accommodation on the surface and/or lattice of PB, enhancing Tl+ adsorption by compensating for missed positive charges. This study provides valuable insights into utilizing PB-based materials to enhance the photo-enhanced Tl+ adsorption capacity in a cost-effective, easy-to-synthesize, and environmentally friendly manner.

Photomagnetic Prussian blue nanocubes: Synthesis, characterization, and biomedical applications

Nanoparticles play an important role in biomedicine. We have developed a method for size-controlled synthesis of photomagnetic Prussian blue nanocubes (PBNCs) using superparamagnetic iron oxide nanoparticles (SPIONs) as precursors. The developed PBNCs have magnetic and optical properties desired in many biomedical diagnostic and therapeutic applications. Specifically, the size-tunable photomagnetic PBNCs exhibit high magnetic saturation, strong optical absorption with a peak at approximately 700 nm, and superior photostability. Our studies demonstrate that PBNCs can be used as MRI and photoacoustic imaging contrast agents in vivo. We also showed the utility of PBNCs for labeling and magnetic manipulation of cells. Dual magnetic and optical properties, together with excellent biocompatibility, render PBNCs an attractive contrast agent for both diagnostic and therapeutic applications. The use SPIONs as precursors for PBNCs provides flexibility and allows researchers to design theranostic agents according to required particle size, optical, and magnetic properties.