Surface configuration enables PbSe quantum dot solar cells with efficiency beyond 12%

Lead selenide (PbSe) quantum dots (QDs) are promising materials for optoelectronic devices owing to their strong confinement and high multiple exciton generation. Nevertheless, their full potential remains unrealized, hampered by the challenges of complex synthesis and insufficient passivation. Here, we have devised an optimized surface configuration strategy based on a directly synthesized semiconductive QD ink system. By integrating tailored passivation through a bifunctional molecule, we significantly improved both the optoelectronic properties and the colloidal stability of the QD inks. Consequently, the photovoltaic devices attained a power conversion efficiency (PCE) of 12.07%, marking the highest reported value among all PbSe QD solar cells. Additionally, the QD inks exhibit colloidal stability for over two months, demonstrating outstanding long-term performance. These results emphasize the efficacy of this method in producing high-performance, enduring PbSe QDs for optoelectronic applications.