Substrate-free crystalline 2d bismuthene

Abstract

The present disclosure generally relates to compositions comprising substrate-free crystalline 2D bismuthene, and the method of making and using the substrate-free crystalline 2D bismuthene.

1 . A method of preparing substrate-free crystalline 2D bismuthene nanoflakes, wherein the method comprises a reductive reaction of NaBiO 3  with a capping polymer and a polyol. 
     
     
         2 . The method of  claim 1 , wherein the method comprises steps:
 dissolving the capping polymer in the polyol to form a mixture of the capping polymer and the polyol;   heating the mixture to an elevated temperature for a period of time and then cooling the mixture to ambient temperature;   adding NaBiO 3  to the mixture of the capping polymer and the polyol, and heating the newly formed mixture to an elevated temperature for a period of time; and   cooling the reaction mixture to ambient temperature, thus forming the substrate-free crystalline 2D bismuthene nanoflakes.   
     
     
         3 . The method of  claim 2 , wherein the polyol is ethylene glycol, the capping polymer is polyvinylpyrrolidone (PVP). 
     
     
         4 . The method of  claim 2 , wherein the substrate-free crystalline 2D bismuthene nanoflakes are characterized by a substantially equilateral triangle shape. 
     
     
         5 . The method of  claim 2 , wherein the substrate-free crystalline 2D bismuthene nanoflakes are characterized by an X-ray diffraction pattern (CuKα radiation, λ=1.54056 A) comprising a peak at 26.16 (2θ±0.1°), and optionally one or more peaks selected from the group consisting of 36.99, 38.64, 47.67, and 55.14 (2θ±0.1°). 
     
     
         6 . The method of  claim 2 , wherein the substrate-free crystalline 2D bismuthene nanoflakes are characterized by a thickness between 3.8 nm to 4.5 nm.