Incident light adjustable solar cell by periodic nanolens architecture

Abstract

Could nanostructures act as lenses to focus incident light for efficient utilization of photovoltaics? Is it possible, in order to avoid serious recombination loss, to realize periodic nanostructures in solar cells without direct etching in a light absorbing semiconductor? Here we propose and demonstrate a promising architecture to shape nanolenses on a planar semiconductor. Optically transparent and electrically conductive nanolenses simultaneously provide the optical benefit of modulating the incident light and the electrical advantage of supporting carrier transportation. A transparent indium-tin-oxide (ITO) nanolens was designed to focus the incident light-spectrum in focal lengths overlapping to a strong electric field region for high carrier collection efficiency. The ITO nanolens effectively broadens near-zero reflection and provides high tolerance to the incident light angles. We present a record high light-conversion efficiency of 16.0% for a periodic nanostructured Si solar cell.

Mie resonance-mediated antireflection effects of Si nanocone arrays fabricated on 8-in. wafers using a nanoimprint technique

“…Surface-concentrated light generates photoexcited carriers near the space charge region, where the built-in potential readily separates the electron-hole pairs. This can boost the carrier collection efficiency of such nanostructure-based solar cells [16,17]. Figure 6 shows the PL spectra of a planar Si wafer and the NC array.…”

“…The advantages of Si as an active material for a PV device include abundance on earth, competitive fabrication cost, and superior device performance. Further efforts to lower the cost to generate electricity have led to light-trapping strategies that improve optical absorption in Si [2][3][4][5][6][7][8][9][10][11][12][13][14][15][16][17]. For example, nanostructures exhibit remarkable absorption enhancement, and a graded refractive index and scattering enable desirable antireflection effects [2][3][4][5][6][7][8][9][10][11][12][13].…”

Si photodetectors imprinted with ITO nanodomes for enhanced photodetection at NIR wavelengths

“…By removing the PMMA and UV-resin layer using lift off method, we can obtain the ITO nanodomes patterns on the surface of Si substrate. The preparation procedure of ITO nanodomes is elsewhere given in our previous research work in detail [15]. …”

“…Since the ITO nanodome structures act as an optical lens which competently converge the incident photons into the junction [15,25], improved EQE and IQE values are yielded by the nanodome structured device.…”

Probing the hot spot properties of semicontinuous gold films through the fluorescence polarization of CdSe/CdS colloidal nanocrystals

“…Metamaterials 1 and many optical cavities such as photonic crystals 2 have been engineered over the past few years. They cover a wide range of applications, including quantum information processing, 3 solar cells for photovoltaic, 4 or efficient analytical sensing in chemistry and molecular biology. 5 An alternative strategy consists in using random structures without long-range spatial correlations in their geometry.…”