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This report explains a transparent perovskite solar cell that replaces ITO on both electrodes with continuous ultra-thin metal films, together with the wet, low-temperature process used to make the electrodes and the fields where the cell can be applied. The full report is available in Korean. An English summary is provided on this page.
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Summary
Transparent perovskite solar cells can turn surfaces that silicon cannot easily reach, such as building facades, windows and vehicle glass, into generating surfaces. ITO, the usual transparent electrode, brings high-vacuum sputtering, dependence on indium supply and brittleness. Thin metal films grow as islands and usually become continuous only above 20-50 nm, so semitransparent cells have relied on opaque grid electrodes, which in turn demand perovskite grains several micrometres wide so that charge can travel sideways to the grid. The structure covered here removes ITO from both electrodes and builds the device only from continuous 5-8 nm metal films (Ag or electroless Cu) formed on a PEIE amine seed layer. Because continuous metal covers both faces, charge only has to move vertically from where it is generated to the electrode above or below, while the metal film carries the lateral current. The process goal shifts from growing large crystals to making the electrode continuous, and dense columnar perovskite grains that run from top to bottom are enough. The two electrodes use the same metal but are split into hole- and electron-collecting electrodes by designing the dipoles of the interface functional groups in opposite directions (effective work-function difference of at least 1.0 eV, a value stated in the patent claims). A multidentate isolation layer, whose molecules bind the metal at three or more sites, blocks interdiffusion between metal and halide, while an orientation-inducing interface layer and exciton-dissociation interface modules align crystal orientation with the charge-extraction path. The bottom electrode is made by surface-limited electroless plating that reduces Cu only on the PEIE surface. The top electrode is formed in advance on the transparent cover and bonded to the perovskite stack by low-temperature dry lamination between room temperature and 50 °C. Top-electrode formation and encapsulation finish in a single step, and because every step is a solution or dry process at 150 °C or below, vacuum sputtering, indium and high-temperature firing drop out of the process. Applications include transparent power-generating glass that passes visible light and generates from ultraviolet and near-infrared light, a four-terminal tandem overlay placed independently on existing silicon modules, vehicle glazing and greenhouses. The key components correspond to the claims of nine Cools patents. The report walks through the mechanism, quantitative design indicators and manufacturing process of each component, and keeps the nature of each figure as the original states it (design value, claimed value or literature value).
Conclusion
The electrode problem in transparent perovskite cells starts with the vacuum process and indium dependence of ITO, and with the tendency of thin metal to form islands instead of a continuous film. When a semitransparent cell uses grids, charge must be collected sideways, which calls for grains several micrometres wide, and growing uniform grains over large areas becomes an obstacle to volume production. The structure in this report turns the task from growing crystals into making the electrode continuous. When continuous 5-8 nm metal films (design value) on a PEIE amine seed layer cover both faces and carry the lateral current, columnar grains that run from top to bottom are sufficient. The two electrodes are made of the same metal and are split into hole and electron collection by reversing the dipole direction of the interface functional groups. The original gives a work-function difference of at least 1.0 eV as a claimed value, and about 5.3-5.5 eV on the hole side and about 4.0-4.2 eV on the electron side as design settings. A multidentate isolation layer with three or more binding sites blocks metal-halide interdiffusion; the original lists a binding energy of at least 0.13 eV and metal penetration of 5 nm or less after 500 h at 85 °C as claimed design indicators. An orientation-inducing interface layer and exciton-dissociation interface modules align crystal orientation with the charge-extraction path. On the manufacturing side, the bottom electrode is made by surface-limited electroless plating that reduces only the Cu ions anchored on PEIE, and the top electrode is formed on the transparent cover in advance and bonded by low-temperature dry lamination at room temperature to 50 °C and 0.05-0.3 MPa (initial DOE conditions). The electroless solution never touches the perovskite, top-electrode formation and encapsulation are merged into one step, and with every step at 150 °C or below, vacuum sputtering, indium and high-temperature firing drop out of the process. Only the current-collection areas outside the light path are thickened on the same wet line to handle large-area current collection. In application, the cell is an independent transparent generator rather than an accessory to silicon tandems. As power-generating glass that passes visible light and absorbs ultraviolet and near-infrared light, it fits building facades and windows, and the original sets visible transmittance of 90% or more as a target stated in the patents. When combined with silicon, a four-terminal overlay keeps the lifetime risk of perovskite separate from the silicon module. The figures in the report are design values, claimed values and literature values; the original does not present measured device efficiency or lifetime.
Topics
- Solar
