Due to the forthcoming shortage of natural resources, the demand for more efficient and eco-friendly chemical processes for the conversion of energy and substance, especially with respect to carbon management, is growing rapidly. Therefore, a search for high-performance solar energy conversion systems to end the current carbon economy era is of paramount importance in both academic and industrial sectors. In this regard, this talk aims to bring together experts from a variety of disciplines in order to discuss the latest fundamental progress in solar water splitting by doping-treated bismuth vanadate (BiVO4) and printable and flexible photovoltaics by oCVD (Oxidative Chemical Vapor Deposition) polymers. oCVD is a solvent-free conformal vacuum-based technique to enable thin-film fabrication of insoluble polymers at moderate vacuum (~ 0.1 Torr) and low temperature (25 – 150 °C). Moreover, oCVD carries the well-cited vacuum processing benefits, such as easy patterning, well-defined thickness control, large-area uniformity, and inline integration with other standard vacuum processes (e.g., vacuum thermal evaporation). Based on these technical advantages from oCVD, polyselenophene, poly(3,4-dimethoxy-thiopehne), and polythiophene have been successfully incorporated into organic photovoltaics as donor, neutral hole transporter, and photoactive neutral hole transporter, respectively. Efficient, sustainable, and large-scale solar hydrogen harvest requires the development of suitable photocatalysts for photoelectrochemical (PEC) cells and artificial water photolysis systems, both of which are able to cost-effectively convert sunlight energy into gaseous hydrogen (H2). To develop such appropriate photocatalysts, their atomic structure control is of primary importance since their functionalities (e.g., electronic band frame, electric properties, kinetics, etc.) are governed by their atomic structure. In this regard, BiVO4’s atomic structure has been engineered via phosphorus, indium and molybdenum doping. The significantly enhanced photo-responsive characteristics of doping-treated BiVO4 have been studied within experimental and theoretical domains.