The ability to design anisotropic nanoparticles with tailored aspect ratio and to order them into large 3-D arrays is an important challenge that scientists have to face to create functionalized nanomaterials. Our approach to control the size and shape of nanoparticles as well as the overall texture of nanoparticulate thin films is to tune their direct aqueous hydrolysis-condensation growth onto substrates by monitoring the interfacial thermodynamics of nanocrystals as well as their kinetics of heteronucleation. Growing materials at very low interfacial tension, i.e. at thermodynamically stable conditions, allows the experimental control of the extension and rate of the nucleation stage and therefore different sizes, shapes, and orientations can be generated onto various substrates. Consequently, the design of novel devices with tailored and engineered three-dimensional architecture can be obtained without template, surfactant, or applied field. Such ideas will be demonstrat ed and illustrated on the design of transition metal oxides at nano-, meso-, and microscale, their growth as 2-D and 3-D arrays with controlled orientations onto various substrates, and their applications for energy technologies.