Nanotechnology is the study of objects whose size varies in the range of nanometers--that is a billion times smaller than a meter. Although humans have been known to use nanotechnology since the ninth century, its role became prominent with the rise of information technology, with most of our current technologies like the smart phones, satellites and rovers on mars, depending on nanotechnology. We have just started uncovering the properties of the different elements and molecules at this scale, giving rise to new technologies as we do. In the Indian Institute of Science, Bengaluru, a team of researchers has been looking at the behavior of impurities in nanomaterials.. At the nanometer scale a single molecule of impurity could interact with several nanoparticles that form the material, thus affecting its efficiency. On the other hand, if we could control the behavior of the impurity within the material it could lead to new discoveries and spawn new technologies. The study shows that the position of the impurity during the formation of the nanomaterial decided the fate of the impurity, which could help in developing self purifying nanocrystals, where the impurities are expelled during the formation of the nano crystal. Or by controlling the position of the impurity, during the nanocrystal growth, new types of soft nano materials could be also designed. The study could be a stepping stone towards understanding and exploiting the role of impurities within nanomaterials.