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Highlights Additive-assisted layer-by-layer (LBL) deposition enables organic solar cells to achieve an unprecedented power conversion efficiency of 20.8%, the highest efficiency to date. The gradient fibrillar morphology enabled by additive-assisted LBL processing promotes the formation of bulk p-i-n structure, improving exciton and carrier diffusion, and reducing recombination losses. The wrinkle pattern morphology achieved by additive-assisted LBL processing is constructed to enhance the light capture capability.

Organic solar cells based on narrow bandgap small-molecule acceptors (SMAs) with highly crystalline characteristics have attracted great attentions for their superiority in obtaining high photovoltaic efficiency. Employing highly crystalline SMAs to enhance power conversion efficiencies (PCEs) by regulating and controlling morphology and compatibility of donor and acceptor materials has turned out to be an effective approach. In this study, we synthesized three different crystalline SMAs by using fluorine substitution on alkoxyphenyl conjugated side chains to modulate the relationship of crystallinity and morphologies, namely ZY1 (zero F atoms), ZY2 (two F atoms), and ZY3 (four F atoms). The three SMAs show the broad absorption edges and similar frontier orbital energy levels, generating the analogical (over 0.9 ​V) open circuit voltage (VOC) of the polymer solar cells (PSCs). As a result, the PM6:ZY2-based PSCs yield a PCE of 10.81% with a VOC of 0.95 ​V, a short-circuit current density (JSC) of 16.154 ​mA ​cm−2, and a fill factor (FF) of 0.71, which is higher than that of 9.17% (PM6:ZY1) and 6.37% (PM6:ZY3). And the PCE (17.23%) of the PM6:Y6:ZY2 based ternary PSCs is also higher than that of 16.32% PM6:Y6 based binary device. Obviously, the results demonstrate that adding fluorine atoms on the conjugated side chains to construct high crystalline materials is a positive strategy to effectively increase the efficiencies of binary and ternary PSCs.

The title complex, [Cd(C14H6O8S2)(C10H8N2)2]n, exhibits a chain-like polymeric structure with 9,10-dioxoanthracene-1,5-disulfonate anions bridging CdII atoms in a bis-monodentate mode. The CdII atom shows a distorted octahedral environment, with four N atoms from two chelating 2,2′-bipyridine ligands forming the equatorial plane and two sulfonate O atoms from two 9,10-dioxoanthracene-1,5-disulfonate anions occupying the apical positions. Weak C—H...O hydrogen-bonding contacts and π–π interactions [centroid–centroid distances = 3.6920 (12) and 3.7095 (12) Å] connect the complex molecules into a three-dimensional supramolecular framework.

The title compound, [MoF2O2(C12H8N2)], has non-crystallographic mirror symmetry. The MoVI atom shows a distorted octahedral environment, with the phenanthroline N atoms and the two oxide groups forming the equatorial plane and the F atoms occupying the apical positions. Weak C—H...O and C—H...F hydrogen-bonding contacts and π–π interactions [centroid–centroid distance = 3.662 (1) Å] connect the complex molecules into a three-dimensional supramolecular framework.