Photovoltaic Performance of Inorganic-Organic Heterojunction Solar Cells Using Boron-Doped Silicon Nanoparticles with Controlled Conductance

Keita Kato; Keisuke Sato; Naoki Fukata; Kenji Hirakuri

doi:10.1166/jnn.2019.15827

Photovoltaic Performance of Inorganic-Organic Heterojunction Solar Cells Using Boron-Doped Silicon Nanoparticles with Controlled Conductance

J Nanosci Nanotechnol. 2019 May 1;19(5):2913-2924. doi: 10.1166/jnn.2019.15827.

Authors

Keita Kato¹, Keisuke Sato¹, Naoki Fukata², Kenji Hirakuri¹

Affiliations

¹ Department of Electrical and Electronic Engineering, Tokyo Denki University, 5 Senju-Asahi-cho, Adachi-ku, Tokyo 120-8551, Japan.
² International Center for Materials Nanoarchitectonics, National Institute for Materials Science, 1-1 Namiki, Tsukuba, Ibaraki 305-0044, Japan.

PMID: 30501800
DOI: 10.1166/jnn.2019.15827

Abstract

We fabricated p-type boron (B)-doped silicon nanoparticles (SiNPs) with a mean diameter of 3.4 nm by a complex chemical reaction of inexpensive pure Si and pure B powders using a combination of ultra-high-speed mixing and thermal annealing techniques. The hole concentration in the p-type SiNPs increased with increasing Si:B blend ratio because of the incorporation of electrically active B atoms into the SiNP core; thus, the conductance of the p-type SiNPs was also enhanced by increasing the mobile carrier concentration. Furthermore, we discuss the effect of the Si:B blend ratio on the photovoltaic performances of the heterojunction solar cells consisting of poly(3,4-ethylenedioxythiophene) doped with poly(styrenesulfonate) (PEDOT:PSS)/p-type SiNPs/n-type Si with a micro-pyramidal structure. The photovoltaic parameters decreased with increasing Si:B blend ratio because of the influence of the insufficient collection rate of the separated charge carriers resulting from reduction in the pn junction region and increase in the carrier recombination. This resulted in the highest power conversion efficiency of 2.57% at a low Si:B blend ratio. These findings are important for designing heterojunction solar cells using p-type SiNPs.