The identification of materials that can efficiently harvest sunlight and store solar energy in chemical bonds will build renewable energy generation potential and also replace the polluting and energy-intensive processes currently used to manufacture many important chemicals. The goal of this research is to demonstrate photocatalytic transformations using novel nanostructures composed of 2D materials (graphene, carbon nitride), polymer templating agents, and inorganic nanocrystals (titania). These graphene composites will be built using bottom-up strategies that exploit inherent interactions between the graphene and carbon nitride sheets, and from well-defined titania nanocrystals sandwiched between the layers of the two 2D semiconductors. The nanocrystals are used to absorb light and speed up reactions by serving as a photocatalyst and will be designed to control charge flow and adsorption and reaction sites to maximize efficiency. The characteristics observed through this research will identify materials for use in the sustainable photocatalytic conversion of water and CO2 and also inform fundamental knowledge around novel photocatalytic systems which can be extended to other solar energy applications.