Visible-light photoredox catalysis has emerged as a central strategy in modern synthetic chemistry, enabling the activation of traditionally inert bonds under mild and environmentally benign conditions. By using visible light as a renewable energy source, these methods have transformed retrosynthetic planning, providing access to radical pathways and novel reactivity profiles that are difficult to achieve with conventional thermal processes. Homogeneous photocatalysis, primarily mediated by transition-metal complexes and organic dyes, has driven the rapid growth of the field through its tunable redox properties and mechanistic clarity. However, challenges such as limited recyclability, reliance on precious metals, and issues of catalyst separation pose significant obstacles to its large-scale and sustainable application. In contrast, heterogeneous photocatalysis offers a more sustainable and scalable approach. Solid-state photocatalysts, including semiconductors and supported nanomaterials, are robust, recyclable, and compatible with continuous-flow processes, making them better aligned with green chemistry principles. Their ability to minimize catalyst leaching and reduce waste further underscores their potential for industrial adoption. Within this context, our research has expanded into visible-light photoredox catalysis for selective C–H bond functionalization. A key highlight of this work is the development of atomically dispersed photocatalysts that enable undirected para-selective functionalization of aromatic systems addressing longstanding challenges in site selectivity. These catalytic systems combine the advantages of homogeneous and heterogeneous catalysis, offering high activity, recyclability, and tunable reactivity. In parallel, we have been actively involved in utilizing CO2 as a sustainable C1 feedstock. Our recent work demonstrates the transformation of CO2 into a reactive oxygen donor for selective oxidative cleavage of alkenes, as well as its application in carboxylation and γ-lactam synthesis. These studies contribute to the broader goal of integrating carbon capture with value-added chemical synthesis. Additionally, we have explored photocatalytic aqueous reforming processes and plastic valorization strategies, highlighting the potential of light-driven catalysis in addressing energy and environmental challenges.