The continuous rise in atmospheric carbon dioxide (CO2) level poses a major environmental and technological challenge, driving the urgent need for scalable CO2 utilization strategies. This thesis explores functional molecules based on main group elements as a versatile platform for sustainable CO2 conversion and energy device stabilization. In chapter 1, the scientific motivation and current limitations of CO2 capture and utilization are discussed, with emphasis on catalytic valorization approaches such as the cycloaddition of CO2 to epoxides and hydrogenation to value-added products. The role of main-group element chemistry and Frustrated Lewis Pairs (FLPs) in overcoming the challenges associated with transition metal catalysts is introduced, alongside the potential of functional molecular additives in stabilizing next-generation photovoltaic devices such as perovskite solar cells (PSCs). In Chapter 2, a metal-free catalytic system comprising thermally activated silica gel and tetrabutylammonium iodide (TBAI) is developed for the cycloaddition of CO2 to epoxides. This catalyst enables the production of cyclic carbonates with high yields. A continuous-flow reactor was designed and optimized for industrial integration, operating efficiently under mild conditions and compatible with modeled industrial flue gas, with life cycle and economic assessments supporting its practical viability and sustainability. Chapter 3 introduces a Hammett parameter-guided strategy for designing triarylborane Lewis acids to enhance FLPs catalysis. By tuning electronic properties, a family of boranes with improved Lewis acidity was synthesized, achieving much higher turnover numbers for catalytic CO2 hydrogenation under metal-free conditions. Building on this, Chapter 4 reports the synthesis of a covalent triazine framework (B_CTF) embedding both triarylborane (Lewis acid) and triazine (Lewis base) units within a porous network. While the intrinsic FLPs activity of this B_CTF was limited by weak basicity, post-functionalization with an iridium complex restored catalytic activity, providing a proof-of-concept for heterogeneous FLP platforms. Chapter 5 expands the application of boron-based molecules beyond catalysis into energy materials. Functional triarylboranes and boronic acids were applied as additives in perovskite PSCs, either as passivating interfacial layers or precursor additives. These boron compounds stabilized the formamidinium cation and led to improvements in both device efficiency and long-term thermal stability. In summary, this work advances functional molecule design for CO2 valorization and energy technologies, offering scalable, metal-free approaches for tackling key challenges in the transition to a low-carbon future.