Enhanced photovoltaic output of bifacial perovskite solar cells via tailoring photoelectric balance in rear window layers with 1T-WS₂ nanosheet engineering

Abstract

The development of high-quality rear window layers (RWLs) with excellent photoelectric properties is key to achieving a high photovoltaic (PV) output from bifacial perovskite solar cells (b-PSCs). Herein, we propose...

A multifunctional strategy of two-dimensional WS2modified absorbers for efficient planar perovskite solar cells

“…1d, the Raman modes of the E 1 2g and the A 1 g are two characteristic peaks observed at 348 cm À1 and 411 cm À1 , corresponding to the inplane vibration and out-of-plane vibration of the W-S phononic film, respectively. [20][21][22] Moreover, the distance between the two characteristic peaks is approximately 63 cm À1 , indicating that the WS 2 NS maybe a low-layer structure. [20][21][22] Subsequently, X-ray photoelectron spectroscopy (XPS) of the commercial WS 2 NS powder was employed to detect the chemical composition and electronic states of the sample, and the corresponding high-resolution XPS spectra of tungsten (W) and sulfur (S) are provided in Fig.…”

“…[20][21][22] Moreover, the distance between the two characteristic peaks is approximately 63 cm À1 , indicating that the WS 2 NS maybe a low-layer structure. [20][21][22] Subsequently, X-ray photoelectron spectroscopy (XPS) of the commercial WS 2 NS powder was employed to detect the chemical composition and electronic states of the sample, and the corresponding high-resolution XPS spectra of tungsten (W) and sulfur (S) are provided in Fig. 1e and f, respectively.…”

“…The excellent photovoltaic parameters and negligible hysteresis shown by the champion device can be ascribed to the synergistic effect of WS 2 on the perovskite film-forming quality, defect passivation, and charge dynamics. 20,37 displays the steady-state current density and efficiency of the devices by applying a constant bias voltage referred from the maximum output power density points (V MPP ). The V MPP of the PVK-C and PVK-W devices is 0.86 and 0.92 V, respectively.…”

“…15,16 A plethora of recent reports has unambiguously demonstrated that 2D tungsten disulfide (WS 2 ) materials were used as charge transporting layers and/or interlayers in PSCs and organic solar cells (OSCs) due to their high transmittance, high mobilities, and tunable band gaps (band gaps in the range of 1.1-2.1 eV), which shows superior performance to other 2D semiconductors in improving the PCE, dark storage, illumination, and thermal stability. [17][18][19][20] Song et al utilized the high hole mobility of 2D WS 2 (approximately 116 cm 2 V À1 s À1 at room temperature) to replace the conventional organic PEDOT:PSS hole transporting layer (HTL), greatly improving the efficiency and stability of inverted planar PSCs. 17 Furthermore, Gong et al and Yan et al introduced ultra-thin 2D WS 2 interlayers to guide van der Waals type quasi-epitaxial perovskite growth, which effectively suppressed the formation of native defects within perovskites and accelerated detrapping charge extraction, thereby reducing carrier recombination and ultimately improving the photovoltaic performance and stability of the inverted planar PSCs.…”

“…The high transmittance and conductivity of the WS 2 -based HTL were utilized to realize the synchronous improvement of bidirectional photovoltaic performance, which opens a new idea for the wide application of 2D WS 2 in more efficient and stable n–i–p planar PSCs. 20 Therefore, it is urgent to explore a more comprehensive, simple, and multifunctional method to simultaneously boost the film-forming quality (including grain boundaries and surface/interface quality) and electronic properties of absorbers by using 2D WS 2 , and ultimately create more efficient and stable planar PSCs.…”