Band gap, which can be tuned by changing the size of quantum dots (QDs) based on the quantum confinement effect, plays a fundamental role in electrical and optical properties of QDs. However, the tuning of the band gap by changing the size results in a series of intrinsic problems, such as the instability of the extremely small QDs, negative combination with biomolecules because of the large size of QDs, etc. Recently, several new methods have been developed to further study and improve the tuning of the band gap. In this paper, we summarized the recent progress in the fields of tuning the band gap of QDs, including alloyed QDs, core-shell QDs and doped QDs. The review has also prospected the development trend of tuning the band gap as well as their applications.
Graphene,a rapidly rising star on the horizon of material science,has a unique two-dimensional nanostructure as well as exceptional mechanical and electronic properties.Despite its short history,graphene has exhibited great potential in various applications.In order to implement the potential applications,functionalization of graphene is necessary to obtain uniform dispersions for good processability.Two kinds are dominant for functionalization such as covalent and non-covalent methods.The former is based on the formation of covalent bonds,and the latter the interaction among molecules.In this review,we summarized briefly the recent progress of functionalized graphene sheets (FGs) in different fields,such as optoelectronic materials,sensors,energy storage materials,catalytic,reinforcing components and so on,and also prospected the development trend of FGs in the future.
Lü Peng,FENG YiYu,ZHANG XueQuan,LI Yu & FENG Wei School of Materials Science and Engineering,Tianjin University,Tianjin 300072,China
