2D Monoelemental Germanene Quantum Dots: Synthesis as Robust Photothermal Agents for Photonic Cancer Nanomedicine

Abstract

As an ew family member of the emerging twodimensional (2D) monoelemental materials (Xenes), germanene has shown promising advantages over the prototypical 2D Xenes,s uch as black phosphorus (BP) and graphene. However,e fficient manufacture of novel germanene nanostructures is still ac hallenge.H erein, as imple top-down approach for the liquid-exfoliation of ultra-small germanene quantum dots (GeQDs) is presented. The prepared GeQDs possess an average lateral size of about 4.5 nm and thickness of about 2.2 nm. The functionalizedG eQDs were demonstrated to be robust photothermal agents (PTAs) with outstanding photothermal conversion efficacy (higher than those of graphene and BPQDs), superior stability,a nd excellent biocompatibility.A saproof-of-principle,2 DG eQDs-based PTAs were used in fluorescence/photoacoustic/photothermalimaging-guided hyperpyrexia ablation of tumors.T his work could expand the application of 2D germanene to the field of photonic cancer nanomedicine.

Tiny 2D silicon quantum sheets: a brain photonic nanoagent for orthotopic glioma theranostics

“…2d and Fig. S5 online), both of which are higher than those of other reported Xenes including BP [21], antimonene [20], germanene QDs [22], boron [19] and GO NSs [24], also higher than the majority of other reported 2D materials (Table S1 online). As illustrated in Fig.…”

“…Among various photonic nanoagents, atomically thin monoelemental 2D materials (Xenes) have captured considerable attention owing to huge specific surface area, strong optical absorption and tunable lateral size [18][19][20][21][22]. Compared with multi-elemental nanomaterials, Xenes maintain simple and precise compositions, and thus their behavior and toxicity in vivo may be more easily evaluated [23].…”

“…Compared with multi-elemental nanomaterials, Xenes maintain simple and precise compositions, and thus their behavior and toxicity in vivo may be more easily evaluated [23]. Until now, graphene [24], black phosphorus (BP) [21], antimonene [20], germanene quantum dots (QDs) [22], and boron NSs [19] have been successively reported as biocompatible photonic agents for cancer theranostics. Particularly, graphene and black phosphorus are the two typical representatives.…”

Two‐dimensional materials of group‐IVA boosting the development of energy storage and conversion

“…Liquid‐phase exfoliation with the aid of sonication is a perfect choice to simply and massively manufacture germanene. Ouyang et al 77 presented a simple top‐down approach in which germanium power splits into ultrasmall germanene quantum dots (Figure 7). The prepared uniform germanene quantum dots were employed as a photothermal agent, exhibiting outstanding photothermal conversion efficacy, superior stability, and excellent biocompatibility.…”

“…B, Transmission electron microscope image and (c) atomic‐force microscopy image of germanene quantum dots. Reproduced with permission: Copyright 2019, Wiley 77 …”