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

Abstract

Efficient hole transport layer (HTL) is crucial for realizing efficient perovskite solar cells (PSCs). In this study, nickel‐oxide (NiOX) thin‐films are investigated as a potential HTL for PSCs. The NiOX films are prepared by electron‐beam physical vapor deposition at low temperatures. The crystalline properties and the work function are determined by X‐ray diffraction and photoelectric yield spectroscopy. The transmission and the complex refractive index of the films are determined by optical spectroscopy and ellipsometry. Furthermore, PSCs are fabricated and characterized. The short‐circuit current density (Jsc) of the PSC is limited by the optical loss due to the NiOx front contact. The optical losses of the front contact are quantified by optical simulations using finite‐difference time‐domain simulations, and a solar cell structure with improved light incoupling is designed. Furthermore, the electrical characteristics of the solar cell are simulated by finite element method simulations. As a result, it is found that the optical losses can be reduced by 70%, and the light incoupling can be improved so that the JSC can be increased by up to 12%, allowing for the realization of PSCs with an energy conversion efficiency of 22%. Findings from the numerical simulations are compared with experimentally realized results.

Improved Nanophotonic Front Contact Design for High‐Performance Perovskite Single‐Junction and Perovskite/Perovskite Tandem Solar Cells

“…The optical constants of materials were either determined through ellipsometry measurement or adopted from the earlier published work. [18,35] The complex refractive index of materials is provided in Supporting Information (Figure S4, Supporting Information). The optical wave propagation for the device was modeled for a wavelength ranging from 300 to 800 nm close to the perovskite absorber bandgap.…”

“…More details on the FEM simulation can be found in the Section S2, Supporting Information, and the literature. [35,55] Furthermore, several key electronic properties of the material needed for FEM calculation were compiled from previous experimentally determined values reported in the literature [18] and are summarized in Table S1, Supporting Information.…”

“…[6,32] In contrast, substrate configuration enables the fabrication of solar cells on various substrates, including plastic and other flexible substrates. [33][34][35] Furthermore, substrate configuration also permits fabricating the PSC as a top cell on a bottom cell in the case of perovskite-based high-efficiency TSCs. [23,[36][37][38] In both superstrate and substrate cases, the perovskite absorber is sandwiched between ETL and HTL.…”

Геттерирующие Свойства Никеля В Кремниевых Фотоэлементах

“…Введенные атомы никеля легко формируют кластеры как в приповерхностной области, так и в объеме [1]. Эти кластеры действуют как геттерирующие центры [17,18] для различных неконтролируемых примесей (O, Cu, Fe, Au) и других дефектов различной природы. Геттерирующие свойства кластеров в приповерхностной области будут очень заметными из-за высокой концентрации атомов никеля.…”

Performance Analysis of Calcium-Doped Titania (TiO2) as an Effective Electron Transport Layer (ETL) for Perovskite Solar Cells

“…Perovskite solar cells (PSCs) have shown rapid and immense enhancement in power conversion efficiency (PCE), majorly attributed to carrier mobility [2]. The PSCs have exceptional optoelectronic properties due to low cost [3], rapid extraction, the transportability of the electron transport layer (ETL), and the electron blocking properties of the hole transport layer (HTL) [4][5][6]. Studies have shown that the engineering of interfaces and contact layers leads to the enhanced photovoltaic performance of PSCs [7].…”