Tellurophene-based metal-organic framework nanosheets for high-performance organic solar cells

Two-dimensional metal organic framework nanosheets demonstrate various applications in chemical separation and purification, biological recognition and sensing, catalysis, and optoelectronics, though the exfoliation of metal organic framework nanosheets with good dispersibility are challenging. Here we report an efficient method for exfoliating a novel tellurophene-based two-dimensional metal organic framework with a branched polymer surfactant polyethylenimine ethoxylate to prepare single- and few-layer nanosheets. Furthermore, the hybrid ink is directly integrated as an electron extraction layer for high-performance organic solar cells, which exhibits enhanced power conversion efficiency in comparison to the polyethylenimine ethoxylate-based ones due to the suppressed charge recombination, tunable work function and improved conductivity. This contribution not only reports a novel method to prepare stable two-dimensional metal organic framework nanosheets but also opens an avenue for their applications in solar cells.