This doctoral thesis focuses on the development of homogeneous single-entity photocatalytic systems based on transition metal complexes for applications in sustainable chemical processes. These systems aim to contribute to current global challenges related to hydrogen storage in the form of Liquid Organic Hydrogen Carriers (LOHCs) and the production of value-added chemicals through light-driven catalytic transformations. To this end, a series of platinum-group organometallic complexes were synthesized and characterized, and their catalytic performance was evaluated under visible-light irradiation in different reaction platforms. The results demonstrate that single-induced transition metal photocatalysis enables chemical transformations under mild reaction conditions while offering improved efficiency and selectivity compared to conventional thermal approaches and dual photocatalytic systems. In addition, mechanistic investigations based on experimental studies provided valuable insight into the underlying reaction pathways and the role of light within the catalytic cycles.
