Photovoltaic Performance of Pin Junction Nanocone Array Solar Cells with Enhanced Effective Optical Absorption

Abstract

The photovoltaic performance of axial and radial pin junction GaAs nanocone array solar cells is investigated. Compared with the cylinder nanowire arrays, the nanocone arrays not only improve the whole optical absorption but more importantly enhance the effective absorption (absorption in the depletion region). The enhanced effective absorption is attributed to the downward shift and extension of the absorption region induced by the shrinking top, which dramatically suppresses the absorption loss in the high-doped top region and enhances the absorption in the depletion region. The highest conversion efficiencies for axial and radial GaAs nanocone solar cells are 20.1% and 17.4%, obtained at a slope angle of 5° and 6°, respectively, both of which are much higher than their cylinder nanowire counterparts. The nanocone structures are promising candidates for high-efficiency solar cells.

Enhanced photovoltaic performance of nanowire array solar cells with multiple diameters

“…At 760 nm, photon generation is mainly concentrated on the top of NWs in the uniform-diameter NWA. As the absorption in the middle depletion region mainly contributes to the photocurrent while the photocarriers generated in the top p region quickly recombine due to lack of built-in electric field, the NWA with uniform diameter of 310 nm has poor photoresponse to the incident 760 nm light [6,13]. For the 16-diameter NWA, the photo generation permeates the entire NWs with a diameter of 321, 313, 327, and 332 nm, leading to strong photoresponse to the incident 760 nm light.…”

“…While in the 16-diameter NWA, large diameter NWs including 343, 344, 356, and 381 nm, can support optical modes and have high absorption across the whole NWs. Hence the multiple diameters not only increase the total absorption at certain wavelengths, but also enhance the effective absorption, that is, the absorption by the depletion region, which will directly lead to the enhancement of conversion efficiency [13]. The simulated photo generation profiles are then incorporated into the electrical tool to calculate the terminal J-V characteristics of 16-diameter NWA solar cells.…”

“…The structural parameters of the NW array (NWA) play a critical role in the performance of solar cells as they determine the optical absorption and carrier separation and transportation. So far, many efforts have been made to design the parameters of the NWA, including the morphology, orientation, diameter/periodic (D/P) ratio, diameter, as well as length [12][13][14][15].…”

Parallel Aligned Nickel Nanocone Arrays for Multiband Microwave Absorption

“…Hence, new geometries will give nanostructures exceptional properties not found in conventional bulk counterparts. , For an assembly of single nanostructures, the overall properties and functional performances are further influenced by their mutual orientation. Among of diverse nanostructures, nanocones have gained extensive attention stimulated by their unique applications in magnetic probe microscopy, surface enhanced Raman scattering, , light absorption, , antireflection, , and field emission. − In particular, magnetic nanocones have aroused great interest because of their shape-induced unique magnetic properties which are not achievable by any other shapes. , …”

Performance Enhancement of Ultra-Thin Nanowire Array Solar Cells by Bottom Reflectivity Engineering

“…Thus far, many efforts have been made to improve the optical absorption of the NWA, which plays a key role in the photovoltaic performance of NW solar cells. One way to improve the optical absorption is to tailor the structural parameters, including the diameter, diameter/period (D/P) ratio, geometry, and orientation of the NWA [19][20][21][22][23]. Another way is to introduce other nanostructures, such as semiconductor quantum dots (QDs) or metal nanoparticles, to extend the absorption spectrum or to enhance the absorption efficiency [24,25].…”