The influence of the polymer-stabilizer molecular weight on the spectral luminescence properties of composite sols and coatings containing PbS quantum dots

Abstract

The influence of the polyvinylpyrrolidone (PVP) molecular weight on the stability and spectral luminescence properties of sols of lead sulfide nanocrystals and the related composite coatings has been studied. It is shown that the spectral properties of PbS sols stabilized with low-molecular (PVP) and the related coatings are determined to a great extent by the formation of large particle aggregates in these materials and, accordingly, high level of light scattering. It is effective to use low-molecular PVP for preparing powder materials containing PbS quantum dots (QDs), because it allows one to perform fast powder precipitation and form small semiconductor particles. High-molecular PVP provides high aggregative and sedimentation stabilities of semiconductor nanocrystal sols. This polymer is effective for use in preparing stable QD sols and homogeneous coatings transparent in the visible spectral range.