Opto-electric investigation for Si/organic heterojunction single-nanowire solar cells

Abstract

Recently, silicon single nanowire solar cells (SNSCs) serving as the sustainable self-power sources have been integrated into optoelectronic nanodevices under the driver of technology and economy. However, conventional SNSC cannot provide the minimum energy consumption for the operation of nanodevices due to its low power conversion efficiency (PCE). Here, we propose an innovative approach to combine the n-type silicon nanowires (SiNWs) with p-type poly(3,4-ethylthiophene):poly(styrenesulfonate) (PEDOT:PSS) to form the p + n heterojunction, which shows superior opto-electric performances. Besides, PEDOT:PSS also acts as a natural anti-reflection coating (ARC) with an excellent light-trapping capability, especially in the short-wavelength range. Importantly, the photovoltaic performances of Si/PEDOT:PSS SNSC can be well maintained even in large surface recombination velocity, due to the efficient field-effect passivation of PEDOT:PSS. The minority carrier concentration at outer surface of shallow p + n heterojunction is greatly reduced by the electric field, drastically suppressing the surface recombination compared to the conventional p-i-n homojunction SNSC. Furthermore, larger junction area of p + n heterojunction facilitates the separation of photo-generated charge carriers. These results demonstrate that the Si/PEDOT:PSS SNSC is a promising alternative for micro power application.

Machine Learning Lattice Constants for Cubic Perovskite Compounds

“…For example, compared with conventional III-V and II-VI semiconductors, halide perovskites have facile tunable emissions throughout the entire visible range, which can be achieved by composition control. [31][32][33][34] In the ideal form of cubic perovskite structure ABX 3 , the monovalent A-cation occupies the center of the unit cell, while the divalent B-cation and monovalent X-anions form an [BX6] octahedra that occupies the corners around the A-cation. [35] In lead-halide perovskites with high photovoltaic performance, the A is usually methylammonium CH 3 NH + , B is Pb 2 + , and X is I À .…”

Machine learning the lattice constant of cubic pyrochlore compounds

“…Examples of highly sought application areas include superconductors, [2][3][4][5][6][7][8][9] multiferroic materials, 10,11 giant magnetoresistance, [12][13][14][15][16] catalysts, piezoelectrics, [17][18][19] photoelectronic devices, and luminescence. [20][21][22] The pyrochlore structure belongs to the space group Fd3m, and the unit cell contains eight molecules and four crystallographically nonequivalent sites. 23 The general formulation can also be written as A 2 B 2 X 6 O′ as there are two types of oxygen ions.…”

“…C is usually an oxygen ion, with some exceptions of partial substitutions by other anions such as F and S. The pyrochlore family consists of a wide range of chemistry and the diverse compositions enable a remarkable variation of unique properties that are important in many technological applications. Examples of highly sought application areas include superconductors, 2‐9 multiferroic materials, 10,11 giant magnetoresistance, 12‐16 catalysts, piezoelectrics, 17‐19 photoelectronic devices, and luminescence 20‐22 …”

Machine learning specific heat capacities of nanofluids containing CuO and Al2O3

“…As compared to conventional cooling liquids, nanofluids have enhanced thermal conductivities, which have attracted great attention in heat transfer applications. In many industrial applications, such as energy supplies, 2,3 electronics, 4‐6 and transportation, 7‐12 it would be rather beneficial if the thermal resistance of the heat transfer liquid can be lowered 13‐17 . Other advantages of nanofluids over traditional base fluids include small pressure drops during flows, lowered tendencies of blocking flows, and increased stabilities 18 …”