Functional materials for photovoltaics and hydrogen energy

Photovoltaics and Hydrogen Energy: An Overview
The photovoltaic effect, where light exposure causes materials to produce electricity, is used in photovoltaics (PV) like silicon-based solar cells. Hydrogen energy sources, on the other hand, utilize hydrogen's electrochemical reactions in fuel cells for power generation, producing only water as a byproduct. Challenges exist in both sectors, including efficiency, cost, and sustainability. Alternative solutions like perovskite solar cells (PSCs) and organic solar cells (OSCs) show promise in PV, achieving power conversion efficiencies up to 25.7%, despite stability and efficiency concerns. Hydrogen energy heavily relies on fuel cells and electrolysers, with ongoing efforts to find cost-effective and durable alternatives to traditional platinum-group metal catalysts. Despite advancements, challenges persist in efficiency, durability, and scalability of these technologies. Continued focus on functional materials development is key to overcoming these issues for a sustainable energy future.

Functional Materials in Photovoltaics
The emergence of innovative materials such as perovskites and organic semiconductors has revolutionized photovoltaic technology. The adaptability of perovskites and the solution processability of organic semiconductors, paired with their high absorption coefficients and effective exciton transport, have pushed the efficiency boundaries of photovoltaics. Significant progress has been made using these materials. Notably, perovskite solar cells (PSCs) have demonstrated power conversion efficiencies (PCEs) rivalling those of traditional monocrystalline silicon cells. Furthermore, the integration of perovskite with silicon or organic semiconductors in tandem architectures has resulted in even greater efficiencies. Advancements in interfacial materials and manufacturing processes also promise to mitigate surface recombination and facilitate the production of flexible and lightweight cells. Case studies further illuminate the potential of these materials. A notable example includes a 16% PCE demonstrated by a tandem solar cell comprising perovskite and organic semiconductors. Another achievement by the NREL is the record 29.15% efficiency in a perovskite-silicon tandem solar cell. These successes underscore the significant potential of these material combinations, however, overcoming challenges related to stability, scalability, and environmental impact remains crucial for the future success of these promising photovoltaic materials.