The tri-nuclear Pt(II)-Ru(II)-Pt(II)(RuPt2) and Re(I)-Ru(II)-Re(II)(RuRe2) complexes, synthesized from mononuclear Ru(II) complex were explored for efficient energy conversion through water splitting and CO2 reduction. The catalysts show excellent activity, serving as promising platforms for sustainable energy applications. The study focuses on designing, stepwise synthesis of the catalysts with insights into the multiple components’ contribution to enhanced catalytic performance. Photophysical and electrochemical analyses highlight the role of the complexes as photocatalysts, where the Ru(II)-polypyridyl unit acts as photosensitizer and the Pt(II)/ Re(I)-polypyridyl units as catalytic sites. Synergistic effects among the components lead to stability, improved performance and emphasizes the significance of multi-nuclear M-Ru(II)-M[M= Pt(II), Re(I)] catalysts in promoting cleaner and more sustainable energy sources.