Magnetron Sputtered Zinc Oxide Nanorods as Thickness-Insensitive Cathode Interlayer for Perovskite Planar-Heterojunction Solar Cells

Abstract

Suitable electrode interfacial layers are essential to the high performance of perovskite planar heterojunction solar cells. In this letter, we report magnetron sputtered zinc oxide (ZnO) film as the cathode interlayer for methylammonium lead iodide (CH3NH3PbI3) perovskite solar cell. Scanning electron microscopy and X-ray diffraction analysis demonstrate that the sputtered ZnO films consist of c-axis aligned nanorods. The solar cells based on this ZnO cathode interlayer showed high short circuit current and power conversion efficiency. Besides, the performance of the device is insensitive to the thickness of ZnO cathode interlayer. Considering the high reliability and maturity of sputtering technique both in lab and industry, we believe that the sputtered ZnO films are promising cathode interlayers for perovskite solar cells, especially in large-scale production.

Under the spotlight: The organic–inorganic hybrid halide perovskite for optoelectronic applications

“…These flexible transparent electrodes include poly(ethylene terephthalate) (PET)/ITO, polyethylene naphthalate (PEN)/ITO, PET/IZO, PET/AZO/Ag/AZO, etc. [71,106,[142][143][144][145][146][147][148][149]. Titanium foil has also been employed as both a substrate and electrode, coupled with a transparent conductive carbon nanotube network as the top transparent electrode [138].…”

“…Arylamine derivatives have received a great interest, showing comparative or even better performances than spiroOMeTAD [104,162,163,174,200,201,202,203,204,205,206]. Besides, other molecular design is appearing recently [149,[207][208][209][210][211]. Inspired by the success of OPV materials, some acceptor-donor-acceptor (A-D-A) type small molecules have been synthesized and employed as HTLs, showing high conductivities and tunable energy alignments [208,210,211].…”

“…The compact layer has been fabricated through various approaches such as electro-deposition [106], magnetron sputtering [149], and sol-gel approaches [148]. In some cases, device performance is insensitive to the thickness of the ZnO layer, which is ascribed to the high electrical conductivity of the ZnO film [149]. Over 15% PCE was observed for devices based on the ZnO with perovskite films fabricated through two-step methods, effectively omitting a prolonged heating process [148].…”

One-Dimensional Electron Transport Layers for Perovskite Solar Cells

“…Hydrothermal growth of ZnO NRs is most commonly used compared to other methodologies like the galvanic cell-based methods [136], electrochemical methods [76,139,140], and magnetron sputtering [133] because of its flexibility in morphology tuning by adjusting conditions like growth time, growth temperature, precursor concentration, and addition of capping agents in the precursor [60,62,141]. In the hydrothermal growth of ZnO NRs, a thin seed layer of ZnO is deposited over the substrate by spin coating, sputtering, or chemical vapor deposition.…”

Electron transport layer driven to improve the open-circuit voltage of CH3NH3PbI3 planar perovskite solar cells

“…These chemical processes mold different morphologies at nanoscale, e.g., nanorods [28] and nanoparticles [29], with a better infiltration and absorption for perovskite films. Nevertheless, to further simplify these chemical approaches for large-scale film fabrication, a few advanced deposition techniques have been developed, for instance, the plasma-enhanced chemical vapor deposition (PECVD) [30] and sputtered method [31]. However, all the perovskite films fabricated on ZnO substrate have a low annealing temperature and short annealing time, as the hydroxide in ZnO can accelerate the decomposition of the perovskite films.…”