Researchers Reveal 24.2% Efficient Hexagonal Nanowire MAPbI3 Perovskite Solar Cells

Researchers are striving to improve perovskite solar cell technology as a promising route to low-cost, efficient solar energy, and a new study details a significant advance in light absorption and device performance. Kawshik Nath, Bibekananda Nath, and Ahmed Zubair, all from the Department of Electrical and Electronic Engineering at Bangladesh University of Engineering and Technology, demonstrate a high-efficiency hexagonal nanowire perovskite solar cell with broadband light trapping capabilities. Their innovative design not only minimises light reflection but also enhances charge collection, achieving a power conversion efficiency of 24.2% through optimised geometrical parameters and strategic dielectric embedding, representing a substantial step towards scalable, high-performance thin-film solar cells.

This breakthrough centres on a unique hexagonal nanowire (HNW)-based structure incorporating CH3NH3PbI3, engineered to minimise light reflection and maximise charge collection.

The team achieved broadband absorption and robust polarization insensitivity through improved light-matter interaction, a critical step towards more efficient photovoltaic devices. The research employed finite-difference time-domain (FDTD) analysis to meticulously examine the optical properties of the proposed HNW structure.
Optimisation of key geometrical parameters, diameter, period, and fill ratio, allowed for precise tuning of both optical characteristics and overall device performance. To further amplify photon confinement, a dielectric SiO2 sphere was partially embedded within the ITO layer, boosting long-wavelength absorbance and increasing the generation of electron-hole pairs near the active region.

Experiments demonstrate a substantial increase in the optical short-circuit current density, reaching 29.53mA/cm2, indicating a higher generation rate and enhanced absorbance. Electrical performance was rigorously assessed by solving the coupled drift-diffusion and Poisson equations, modelling carrier transport dynamics within the device.

The optimised HNW structure ultimately achieved a notable power conversion efficiency of 24.2%, establishing a strong correlation between effective optical confinement and efficient carrier transport. This innovative HNW perovskite solar cell presents a viable pathway towards high-performance photovoltaic systems and scalable thin-film solar technologies.

The rotational symmetry of the HNW configuration yields polarization-independent absorbance under both transverse electric and transverse magnetic illumination across the visible and near-infrared spectra, offering a significant advantage over conventional designs. These attributes position the proposed structure as a promising candidate for next-generation solar energy harvesting.

Optimisation of hexagonal nanowire geometry and dielectric integration for perovskite solar cell performance is crucial

Scientists engineered a hexagonal nanowire (HNW)-based perovskite solar cell to enhance light absorption and charge-collection efficiency. The research team optimized geometrical parameters of the CH3NH3PbI3-based HNW structure, specifically diameter, period, and fill ratio, to influence both optical properties and overall device performance.

This work pioneered a design incorporating a partially embedded dielectric SiO2 sphere within the ITO layer, intensifying photon confinement and boosting long-wavelength absorbance to increase electron-hole pair generation. To analyse the optical characteristics of the proposed structure, researchers employed the finite-difference time-domain (FDTD) method.

Experiments demonstrated that the optimized HNW structure achieved a high optical short-circuit current density of 29.53mA/cm2, indicating enhanced absorbance and a greater generation rate of charge carriers. Electrical performance was then assessed by solving the coupled drift-diffusion and Poisson equations, modelling the dynamics of carrier transport within the device.

The study further details the fabrication of the HNW structure and the precise placement of the SiO2 sphere to maximise light trapping. This innovative approach resulted in a notable power conversion efficiency of 24.2%, establishing a strong correlation between optical confinement and effective carrier transport.

The team harnessed rotational symmetry within the HNW configuration to yield polarization-independent absorbance across both TE and TM illumination in the visible and near-infrared spectra. This design renders the proposed HNW PSC a promising candidate for high-performance photovoltaic systems and scalable thin-film solar technologies.

Optimised nanowire geometry enhances perovskite solar cell light absorption and efficiency

Scientists have developed a hexagonal nanowire (HNW)-based perovskite solar cell (PSC) demonstrating enhanced light absorption and polarization insensitivity. The research focused on optimizing light-matter interaction and increasing charge-collection efficiency within the device structure. Experiments revealed a peak optical short-circuit current density (Jsc) of 29.53mA/cm2, achieved through careful geometrical design and the incorporation of a dielectric SiO2 sphere.

The team measured the absorbance spectra for varying nanowire diameters, maintaining a fill ratio of 0.5, and found that decreasing the radius from 110nm to 150nm broadened and uniformed absorbance between 450-800nm. This improvement resulted from enhanced light confinement and photonic coupling within the perovskite nanowires.

Data shows a peak optical Jsc of 24.01mA/cm2 was observed at a radius of 150nm, with larger radii exhibiting decreased absorbance, particularly in the 600-800nm range. Further optimization involved varying the fill ratio (FR) while maintaining a constant radius of 150nm. Results demonstrate that FR values between 0.7 and 0.9 improved Jsc and light absorbance, indicating favorable photonic coupling.

The optimum configuration, with a nanowire diameter of 300nm and an FR of 0.9, yielded a peak optical Jsc of 26.09mA/cm2. Subsequent optimization of the electron transport layer (ETL) and hole transport layer (HTL) layers increased this value to 27.02mA/cm2. Measurements confirm that the optimized HNW structure, exhibiting absorbance values greater than 85% between 450 and 780nm, effectively harvests light due to strong light-matter interaction facilitated by the hexagonal structure.

To further enhance performance, a dielectric SiO2 sphere was incorporated, achieving a maximum optical Jsc of 28.2mA/cm2 with an 82nm radius. Partially embedding the SiO2 sphere into the ITO layer redirected light into the perovskite region, increasing electron-hole pair generation. The breakthrough delivers a notable power conversion efficiency of 24.2%, highlighting a strong connection between optical confinement and effective carrier transport. Tests prove the proposed HNW PSC is a viable option for high-performance photovoltaic systems and scalable thin-film solar technology.

Hexagonal nanowire architecture boosts perovskite solar cell performance by enhancing light absorption and charge transport

Researchers have developed a hexagonal nanowire (HNW)-based perovskite solar cell demonstrating enhanced light absorption and charge collection efficiency. The innovative design utilizes the rotational symmetry of the HNW structure to achieve polarization-independent absorbance across the visible and near-infrared spectra, improving light-matter interaction.

Optimisation of the nanowire’s geometrical parameters, alongside the partial embedding of a dielectric SiO2 sphere within the ITO layer, further intensified photon confinement and electron-hole pair generation. Detailed optical and electrical simulations revealed a significant reduction in reflectance and transmittance losses, culminating in a power conversion efficiency of 24.2% with a fill factor of 0.85 and open-circuit voltage of 1.02V.

This performance surpasses previously reported efficiencies for similar perovskite solar cell structures, highlighting the benefits of structural photonic design over conventional planar configurations. The authors acknowledge that the data supporting these findings are not currently publicly available but can be requested from them.

Future work could focus on making this data accessible to facilitate further research and development in the field. This study establishes a strong correlation between optical confinement and effective carrier transport within the HNW geometry, offering a pathway to innovative, high-performance perovskite solar cells.

The combination of Mie resonance and Fabry-Pérot cavity effects, facilitated by the SiO2 sphere, contributes to the observed improvements in absorbance and efficiency. While the research presents promising theoretical results, further investigation is needed to assess the scalability and long-term stability of these HNW-based devices in practical applications.