Design of wave-optical structured substrates for ultra-thin perovskite solar cells

Abstract

Photonic micro/nano-structures in the wave-optics regime have shown to be a promising strategy for effective broadband light capture in ultra-thin devices, opening a window of opportunity for cheap, efficient, lightweight and flexible photovoltaics (PV). Here we design, from an optical standpoint, a novel industrially-attractive concept where light trapping is obtained by conformably depositing the solar cell materials onto previously-patterned photonic substrates. This solution is applied and optimized for perovskite solar cells (PSCs) with distinct thicknesses of the perovskite absorber -the conventional (500 nm) and ultra-thin (300 nm) in view of enhanced flexibility -yielding photocurrent improvements up to 22.8% in superstrate cell configuration and 24.4% in substrate-type configuration; thereby coming relatively close to the fundamental Lambertian limits. Furthermore, these structures also show an omni-direction optical response for incidence angles up to 70º for all cases, therefore demonstrating the viability of this light trapping method for implementation in flexible PV devices operating under bending. The photonic-enhanced ultra-thin solar cells designed here ultimately support the reduction of material usage in PSC technology, which is especially beneficial to mitigate lead usage, without impacting the device's performance.

Light-intensity and thickness dependent efficiency of planar perovskite solar cells: charge recombinationversusextraction

“…We note also recent reports that also highlight increased reflection losses in thinner devices. 43,44 The measured J SC is in good agreement with the calculated J SC at 0.1 sun for all devices. In contrast, as light intensity increases the measured J SC is considerably lower than calculated J SC for the thicker devices.…”

Spray Pyrolyzed TiO2 Embedded Multi-Layer Front Contact Design for High-Efficiency Perovskite Solar Cells

“…No scattering or diffraction is noticeable in the planar configuration of the PSC, which also suggests that a significant portion of incident light is lost only due to high reflections. Such reflections can be minimized, and photon absorption can be enhanced in the PSC using multi-layer photonic structures [ 45 ]. The PSC integrated with a front photonic structure can further reduce the UV radiation, improving device stability [ 25 , 45 ].…”

“…Such reflections can be minimized, and photon absorption can be enhanced in the PSC using multi-layer photonic structures [45]. The PSC integrated with a front photonic structure can further reduce the UV radiation, improving device stability [25,45]. However, optical simulations do not provide electrical parameter values for the solar cell; hence, FEM simulations were adapted to investigate the electrical effects of the solar cell by allowing a J-V characteristic curve.…”

Electrical and Optical Properties of Nickel‐Oxide Films for Efficient Perovskite Solar Cells

“…[4,7,8] Typically, planar PSC structures in superstrate configuration facilitate easy fabrication techniques with a low-cost solution. [9][10][11][12][13] On the other hand, PSCs in substrate configuration allows depositing as a top cell for fabricating perovskite/ silicon tandem solar cells Efficient hole transport layer (HTL) is crucial for realizing efficient perovskite solar cells (PSCs). In this study, nickel-oxide (NiO X ) thin-films are investigated as a potential HTL for PSCs.…”