The last two decades have seen the discovery and the subsequent enormous growth in the field of nano- materials. The impact of size upon the properties of materials is now a well-known and well-proven phenomenon. However, the approach for the preparation of desired nano-materials is of prime importance. The chemical (bottom-up) approach has many-fold advantages over the other conventional and non-conventional preparatory methods. This book, therefore, covers the bottom-up approach for preparation of nano-materials and the subsequent uses as reversible hydrogen storage materials. The precursors are designed at molecular level to prepare the desired nano-materials by different techniques. The resulting nano-material consisting of nano-wires is used for reversible hydrogen storage to meet the future energy requirements. The book consists of parts describing synthesis of molecular precursors and hydrogen storage techniques.