Recent advances in perovskite solar cells (PSCs) have resulted in greater than 23% efficiency with superior advantages such as flexibility and solution‐processability, allowing PSCs to be fabricated by a high‐throughput and low‐cost roll‐to‐roll (R2R) process. The development of scalable deposition processes is crucial to realize R2R production of flexible PSCs. Gravure printing is a promising candidate with the benefit of direct printing of the desired layer with arbitrary shape and size by using the R2R process. Here, flexible PSCs are fabricated by gravure printing. Printing inks and processing parameters are optimized to obtain smooth and uniform films. SnO 2 nanoparticles are uniformly printed by reducing surface tension. Perovskite layers are successfully formed by optimizing the printing parameters and subsequent antisolvent bathing. 2,2′,7,7′‐Tetrakis‐( N , N ‐di‐4‐methoxyphenylamino)‐9,9′‐spirobifluorene is also successfully printed. The all‐gravure‐printed device exhibits 17.2% champion efficiency, with 15.5% maximum power point tracking efficiency for 1000 s. Gravure‐printed flexible PSCs based on a two‐step deposition of perovskite layer are also demonstrated. Furthermore, a R2R process based on the gravure printing is demonstrated. The champion efficiency of 9.7% is achieved for partly R2R‐processed PSCs based on a two‐step fabrication of the perovskite layer.

The reaction of SeCl2 with tert-butylamine in various molar ratios in THF at -78 degrees C has been investigated by 77Se NMR spectroscopy. In addition to the known Se-N heterocycles Se6(NtBu)2 (1) and Se9(NtBu)6 (2), the acyclic imidoselenium(II) dichlorides ClSe[N(tBu)Se]nCl (4, n = 1; 5, n = 2) and two new cyclic selenium imides [Se3(NtBu)2]n (3, n = 1 or 2) and Se3(NtBu)3 (6) have been isolated and identified. An X-ray analysis shows that 6 is a six-membered ring in a chair conformation with magnitude of d(Se-N) = 1.833 A. Crystal data: 6, trigonal, P3c1, a = 9.8660(3) A, c = 20.8427(7) A, V = 1757.0(1) A3, Z = 6. The 1H, 13C, and 77Se NMR data for 1-6 are reported, and some reassignments of earlier literature data for 1-3 (n = 1) are made. The decomposition of tBuN=Se=NtBu at 20 degrees C in toluene was monitored by 77Se NMR. The major products are 6 and 3. The Se(IV)-N systems tBuNSe(mu-NtBu)2E (7, E = SO2; 8, E = SeO) were prepared by the reaction of a mixture of SeCl4 and excess tBuNH2 with SO2Cl2 or SeOCl2, respectively. Compound 8 is also generated by the cycloaddition reaction of tBuNSeNtBu with tBuNSeO. Both 7 and 8 consist of slightly puckered four-membered rings. The mean terminal and bridging Se-N distances in 7 are 1.665(2) and 1.948(2) A, respectively. The corresponding values for 8 are 1.687(4) and 1.900(4) A, and d(Se=O) = 1.628(4) A. Crystal data: 7, monoclinic, P2(1)/c, a = 18.669(4) A, b = 12.329(2) A, c = 16.463(3) A, beta = 115.56(3) degrees, V = 3418.4(11) A3, Z = 4; 8, triclinic, P1, a = 6.372(1) A, b = 9.926(2) A, c = 14.034(3) A, alpha = 99.320(3) A, beta = 95.764(3) A, gamma = 103.876(3) A, V = 841.3(3) A3, Z = 2.

The selenium(IV) diimide AdN=Se=NAd (Ad = 1-adamantyl) adopts a monomeric structure with a Z,E configuration in the solid state whereas the seleninylamine OSe(mu-NBut)2SeO crystallizes as the cis-dimer.