Materials Chemistry and Physics, Vol.199, 67-72, 2017
Er3+-doped tellurite glasses for enhancing a solar cell photocurrent through photon upconversion upon 1500 nm excitation
Trivalent erbium-doped tellurite glasses have been prepared and investigated with an aim to improve the efficiency of a Silicon (Si) solar cell through photon upconversion processes. The upconversion emissions and 975 nm (I-4(11)/ at 548 nm (S-4(3/2), H-2(11/2) -> I-4(15/2) , 671 nm (F-4(9/2) -> I-4(15/2)), 800 nm (I-4(9/2) -> I-4(15/2)) of Er3+ ions have been observed under 1500 nm laser excitation. The 3.0 mol% Er2O3-doped glass exhibits high upconversion emission at 975 nm compared to 0.01 and 0.5 mol% Er2O3-doped glasses. Temporal evolution studies confirm that energy transfer upconversion is responsible for observed upconversion emissions, which is in good agreement with a simple rate-equations model. The upconversion intensity and photocurrent of solar cell are found to increase with the increase of pump power of the laser. A significant enhancement in photocurrent of a solar cell has been observed, when the 3.0 mol% Er2O3-doped glass is placed over a solar cell under 1500 nm laser excitation. All the results indicate that 3.0 mol% Er2O3-doped glass could be suitable for enhancing the solar cell efficiency. (C) 2017 Elsevier B.V. All rights reserved.