Numerical investigation on performance of ultra-thin GaAs solar cells enabled with frontal surface pyramid array

Abstract

In this paper, the optical and electrical characteristics of ultra-thin GaAs solar cell with front-surface pyramid array are investigated systematically. The results show that the cell with pyramid array could significantly improve the photon absorption efficiency due to synergistic effects of antireflection and diffraction compared with reference solar cells with single and double anti-reflective coating (ARC), and the maximal integrated quantum efficiency of 0.88 is obtained for pyramid cells, much higher than that of 0.75 and 0.71 for double and single ARC solar cells, respectively. Electric simulation demonstrates the total recombination rate of solar cell with pyramid array is higher than that of reference solar cells due to higher carrier concentration. The radiative recombination dominated in the base and emitter region, while the SRH recombination becomes the primary recombination mechanism in the space charge region, both which are much higher than Auger recombination. Surface recombination has little impact on the photovoltaic performance due to the presence of wide bandgap window layer. For pyramid cell, the J_sc,V_oc,η of 22.65mA/cm2, 1.120V and 21.84% are obtained when considering photon recycling effect, respectively, are higher than those of 19.52mA/cm2, 1.106V and 18.72% for double ARC solar cell, and those of 18.32mA/cm2, 1.106V and 17.60% for single ARC solar cell.

Advancements in Enhancing Antibacterial Properties of Cotton Fabric through Chitosan and Nanoparticles

“…[99] According to Peng et al, modified chitosan-based nanosilver has a notable inhibitory impact on typical bacterial infection and diminishes the incidence of umbilical cord wound inflammation. [100] Shehabeldine et al investigated the antimicrobial and antiviral properties of long-lasting cotton garments treated with nanoparticles of zinc oxide, acyclovir, clove oil, and nano chitosan. The results showed that the treated cotton garments had more promising antibacterial action towards Gram-positive bacteria than Gram-negative bacteria.…”

Comparative optical analysis of GaAs nanostructures for photovoltaic applications using finite element method

“…In order to reduce the cost and optical losses, various strategies to reduce the reflection and enhance the absorptance by utilizing random or periodically arranged nanopatterns or plasmonic nanoparticles are implemented [11,12]. In addition to this, different nanostructures such as nanocones [13,14], nanoholes [15][16][17], nanowire [13,14], nanopyramids [18][19][20], funnel [13], inverted nanopencil [21] etc used in the active layer of SCs can improve the light trapping and carrier collection efficiency to a large extent in comparison to the thin film planar SCs. Arrays of different nanostructures act as perfect light absorbers due to their ability to optimize the optical path length of incident photons and reduce their escape probability from the surface and relax the stringent criterion of lattice matching for the growth of different materials on flexible and low-cost substrates [13].…”

“…GaAs is widely used for photovoltaic and photothermal applications due to its superior optoelectronic properties such as direct bandgap, high mobility, high absorption coefficient and ideal solar spectral response [22,23]. However, the high manufacturing cost of GaAs materials restricts its usage in terrestrial applications and necessitates the thinning of the active layer to reduce material cost, purity and crystallinity requirements [20,24]. Thin film GaAs SCs suffer from low photoconversion efficiency due to limited absorption by the thin active layer.…”