<p>➀ Researchers at the University of New South Wales have developed a hydrogen annealing technique that enhances the efficiency of CZTS solar cells, achieving a record 11.4% efficiency.</p><p>➁ The technique involves heating the solar cell material in a hydrogen environment, which redistributes sodium and passivates defects, improving carrier transport.</p><p>➂ This breakthrough could pave the way for more efficient and sustainable solar energy solutions, potentially pushing CZTS efficiency beyond 15%.</p>