Hybrid organic-inorganic materials are a new class of material used as interfacial layers in polymer solar cells. A hybrid material, composed of antimony as inorganic part and diaminopyridine as organic part, is synthesized and described as a new material for electron extraction layer in polymer solar cells and compared to the recently demonstrated hybrid materials using bismuth instead of antimony. The hybrid compound is solution-processed onto the photoactive layer based on a classical blend, composed of PTB7-Th low bandgap polymer as donor mixed with PC70BM fullerene as acceptor material. By using a regular device structure and an aluminum cathode, the solar cells exhibited a power conversion efficiency of 8.42%, equivalent to the reference device using ZnO nanocrystals as interfacial layer, and strongly improved compared to bismuth-based hybrid material. The processing of extraction layers up to a thickness of 80 nm of such hybrid material reveals that the change from bismuth to antimony has strongly improved the charge extraction and transport properties of the hybrid materials. Interestingly, nanocomposites made of the hybrid material mixed with ZnO nanocrystals in a 1:1 ratio further improved the electronic properties of the extraction layers, leading to power conversion efficiency of 9.74%. This was addressed to a more closely packed morphology of the hybrid layer, leading to further improved electron extraction. It is important to note that these hybrid electron extraction layers, both pure and ZnO-doped, also greatly improved the stability of solar cells, both under dark storage in air and under lighting under inert atmosphere compared to solar cells treated with ZnO intermediate layers.