Algae Extraction Controllable Delamination of Vanadium Carbide Nanosheets with Enhanced Near-Infrared Photothermal Performance

The two-dimensional (2D) vanadium carbide (V2C) MXene has shown great potential as a photothermal agent (PTA) for photothermal therapy (PTT). However, the use of V2C in PTT is limited by the harsh synthesis condition and low photothermal conversion efficiency (PTCE). Herein, we report a completely different green delamination method using algae extraction to intercalate and delaminate V2AlC to produce mass V2C nanosheets (NSs) with a high yield (90 %). The resulting V2C NSs demonstrated good structural integrity and remarkably high absorption in near infrared (NIR) region with a PTCE as high as 48 %. Systemic in vitro and in vivo studies demonstrate that the V2C NSs can serve as efficient PTA for photoacoustic (PA) and magnetic resonance imaging (MRI)-guided PTT of cancer. This work provides a cost-effective, environment-friendly, and high-yielding disassembly approach of MAX, opening a new avenue to develop MXenes with desirable properties for a myriad of applications.