Nanostructures for photon management in solar cells

Abstract

Abstract:The concurrent development of high-performance materials, new device and system architectures, and nanofabrication processes has driven widespread research and development in the field of nanostructures for photon management in photovoltaics. The fundamental goals of photon management are to reduce incident light reflection, improve absorption, and tailor the optical properties of a device for use in different types of energy conversion systems. Nanostructures rely on a core set of phenomena to attain these goals, including gradation of the refractive index, coupling to waveguide modes through surface structuring, and modification of the photonic band structure of a device. In this review, we present recent developments in the field of nanostructures for photon management in solar cells with applications across different materials and system architectures. We focus both on theoretical and numerical studies and on progress in fabricating solar cells containing photonic nanostructures. We show that nanoscale light management structures have yielded real efficiency gains in many types of photovoltaic devices; however, we note that important work remains to ensure that improved optical performance does not come at the expense of poor electrical properties.

Broadband and ultrahigh optical haze thin films with self-aggregated alumina nanowire bundles for photovoltaic applications

“…thiophenediyl}) (PTB7, 1-Material),[6,6]-phenyl C71 butyric acid methyl ester (PC 70 BM, Nano-C) were purchased and then used as received without any purification.Device fabricationThe PFN interlayer material dissolved in methanol with a concentration of 0.5 mg/mL in the presence of a small amount of acetic acid (2 μl/mL) was spin-coated onto a pre-patterned ITO-glass substrate, followed by drying under vacuum for 1 h. The PTB7:PC 70 BM blend (1:1.5 by weight) dissolved in the mixed solvent of chlorobenzene/diiodooctane (97:3 vol/vol) with a total concentration of 25 mg/ml was spin-coated on top of the PFN interlayer to form a 90-nm-thick photoactive layer. The solvent was completely dried in a vacuum chamber for overnight.…”

Emerging solar cells energy trade-off: Interface engineering materials impact on stability and efficiency progress

“…83 Physical review of TiO 2 and ZnO shows significance properties of TiO 2 to ease the electron-cation complex formation and promotes optical efficiency. 85,86 The band edge variation and optical absorption of wide solar spectrum coverage is predictable in TiO 2 or ZnO. 87,88 As compared with ZnO, TiO 2 conduction level supports better conductivity.…”

Periodic molybdenum disc array for light trapping in amorphous silicon layer

“…These include antireflection coatings, photonic crystals, metallic microstructures, etc. [11][12][13][14][15] Metallic microstructure, widely used for light-trapping and reducing thickness of materials and cost of solar cells, is an ideal candidate for improving light absorption in photovoltaic devices. Light-trapping effect of metallic microstructures functionalized thin film semiconductor layers can be generally attributed to several mechanisms: scattering effects, near-field effect and surface plasmon polarition (SPPs), and so on.…”