Cadmium Sulfide (CdS) nanostructures are attractive for applications in semiconductor lasers, light emitting diodes, photovoltaic cells and display devices. The present report is concerned with the growth and characteristics of CdS nanostructures for possible applications in charge storage, nano-capacitor, photovoltaic and photosensing devices. The fabrication of hexagonal, well-arranged porous alumina templates and the growth of CdS nanowires in the templates are discussed. The characteristics of needle- and wire-like CdS nanocomposites grown in a polymer matrix are analyzed. The nanocomposite/conducting polymer device exhibits negative resistance and charge storage characteristics. MWCNT-CdS nanostructures embedded in a conducting polymer shows a broad spectral response (400-1000nm), which is attractive for hybrid photovoltaic devices. The growth of core-shell Ge/CdS radial nanowire heterostructures by a combination of vapor-liquid-solid growth and chemical process is reported. The photodiode behavior of Ge/CdS heterojunction and enhancement of photocurrent with a broadband response from visible to near-IR due to the formation radial heterojunctions are discussed in details.