Controlled Deposition and Performance Optimization of Perovskite Solar Cells Using Ultrasonic Spray‐Coating of Photoactive Layers

Abstract

This study investigated a new film-deposition technique, ultrasonic spray-coating, for use in the production of a photoactive layer of perovskite solar cells. Stable atomization and facile fabrication of perovskite thin films by ultrasonic spray-coating were achieved in a one-step method through manipulating the ink formulation (e.g., solution concentration, precursor composition, and mixing solvent ratio) and the drying kinetics (e.g., post-annealing temperature). The performance of the perovskite solar cells was mainly influenced by the intrinsic film morphology and crystalline orientation of the deposited perovskite layer. By suitable optimization of the spreading and drying conditions of the ink, ultrasonic spray-coated perovskite photovoltaic devices were obtained with a maximum power conversion efficiency of 11.30 %, a fill factor of 73.6 %, a short-circuit current of 19.7 mA cm , and an open-circuit voltage of 0.78 V, respectively. Notably, the average power efficiency reached above 10 %, attributed to the large flower-like perovskite crystal with orientation along the (1 1 2)/(2 0 0) and (2 2 4)/(4 0 0) directions. Thus, the ultrasonic spray-coating method for perovskite photoactive layers, combining advantages of good photovoltaic performance results and benefits from cost and processing, has the potential for large-scale commercial production.

Perovskite Solar Cells: From the Laboratory to the Assembly Line

“…Stable atomization and facile fabrication of perovskite thin films by USC were also exploited by Chang et al,w ho got aP CE of 11.3 %t hanks to the optimization of the spreadinga nd drying conditions of the ink. [139] Heo et al fabricated planar type CH 3 NH 3 PbI 3Àx Cl x PSCs via spray coating with ac ontrolled composition of the solvents, leadingt oc ells with aP CE of 17.8 %( forward scan) and 18.3 % (reverses can) under 1sun conditions. [140] By controlling the ratio of DMF (a quickly evaporating solvent) and g-butyrolactone (GBL, as lowly evaporating solvent), they were able to obtain the largestp erovskite crystal grains by balancing the inward flux of the spray solution with the outward flux of the evaporating solvent ( Figure 7B).…”

A Review of Perovskites Solar Cell Stability

“…The organic–inorganic perovskite with an ABX 3 structure where A is cesium (Cs), methyl ammonium (MA), or formamidinium (FA); B is Pb or Sn; and X is Cl, Br, or I, have recently emerged as an intriguing class of semiconductors . There are various techniques in which perovskites can be processed such as spray coating, a nozzle is used to disperse tiny liquid droplets onto substrates the perovskite layer can also be deposited by ultrasonic spraying . Dip coating, a nonconventional method to create the meniscus edge, is pulling a substrate out of a precursor ink and sheering a cover plate over the deposition substrate, two‐step deposition in which the lead halide thin film is first deposited then converted to the perovskite by reaction with organic halide salts.…”

Scalable solution coating of the absorber for perovskite solar cells

“…Many of the methods originally developed for passive coatings are now being tested for fabrication of functional films in perovskite solar cells. Examples include airbrush coating [2][3][4][5][6][7] , ultrasonic spray coating [8][9][10][11][12][13][14] , ink-jet printing [15][16][17] , slot-die coating [18][19][20][21][22][23][24] , doctor blade coating [25][26][27] , screen printing [28,29] , electrospray coating [30] , and so on.…”

“…[33] . Ultrasonic spray has also been implemented for perovskite absorbers by several groups [8][9][10][11][12][13][14] .…”