This review presents an overview of the dedicated research directions of the Group for Molecular Engineering of Functional Materials (GMF). This includes molecular engineering aspects of sensitizers constructed from ruthenium complexes, organic molecules, porphyrins and phthalocyanines. Manipulation of organometal trihalide perovskites, and charge transporting materials for high performance perovskite solar cells and photo-detectors are also described. Controlling phosphorescence color, and quantum yields in iridium complexes by tailoring ligands for organic light emitting diodes are demonstrated. Efficient reduction of CO2 to CO using molecular catalyst on a protected Cu2O photocathode, and cost-effective water-splitting cell using a high efficiency perovskite solar cell are presented.