Research Article Effect of Surface Morphology and Dispersion Media on the Properties of PEDOT:PSS/n-Si Hybrid Solar Cell Containing Functionalized Graphene Pham Van Trinh, 1 Phan Ngoc Hong, 1,2 Bui Hung Thang, 1 Nguyen Tuan Hong, 3 Duong Van Thiet, 4 Nguyen Van Chuc, 1,2 and Phan Ngoc Minh 1,2,3 1 Institute of Materials Science, Vietnam Academy of Science and Technology, 18 Hoang Quoc Viet Str., Cau Giay Distr., Hanoi, Vietnam 2 Graduate University of Science and Technology, Vietnam Academy of Science and Technology, 18 Hoang Quoc Viet Str., Cau Giay Distr., Hanoi, Vietnam 3 Center for High Technology Development, Vietnam Academy of Science and Technology, 18 Hoang Quoc Viet Str., Cau Giay Distr., Hanoi, Vietnam 4 School of Engineering Physics, Hanoi University of Science and Technology, 1 Dai Co Viet Road, Hai Ba Trung Distr., Hanoi, Vietnam Correspondence should be addressed to Pham Van Trinh; trinhpv@ims.vast.vn and Phan Ngoc Minh; pnminh@vast.ac.vn Received 22 June 2017; Revised 5 October 2017; Accepted 15 October 2017; Published 6 November 2017 Academic Editor: Mikhael Bechelany Copyright © 2017 Pham Van Trinh et al. Tis is an open access article distributed under the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited. We present the results on the efect of surface morphology and dispersion media on the properties of PEDOT:PSS/n-Si hybrid solar cell containing functionalized graphene (Gr). Te hybrid solar cells based on SiNWs showed higher power conversion efciency (PCE) compared to the planar based cells due to suppressing the carrier recombination and improving carrier transport efciency. Te PCE of hybrid solar cells could be improved by adding Gr into PEDOT:PSS. Diferent solvents including deionized (DI) water, ethylene glycol (EG), and isopropyl alcohol (IPA) were used as media for Gr dispersion. Te best performance was obtained for the cell containing Gr dispersed in EG with a measured PCE of 7.33% and nearly 13% and 16% enhancement in comparison with the cells using Gr dispersed in IPA and DI water, respectively. Te increase in PCE is attributed to improving the carrier-mobility, electrical conductivity, PEDOT crystallinity, and ordering. 1. Introduction Traditional sources of energy like petroleum, coal, and natural gas are being depleted of due to high usage rate which is further expected to rise in the future. Solar energy is by far the renewable energy source with the most signifcant potential. Utilization of solar energy is very expensive and therefore not widely used for commercial electricity produc- tion. Demanding for the development of the next generations of solar cell with higher efciency, lower price and longer life are indispensable. Nanomaterials and nanostructures based solar cells hold promising potency to enhance the performance of solar cells by improving both light trapping and photocarrier collec- tion [1, 2]. Many approaches have been taken to lower the production cost of Si PVs, among which thin-flm Si solar cells ofer a promising low-cost solution. However, thin-flm Si solar cells have lower efciency than bulk Si, due to their limited absorption thickness [3–5]. As evidenced by recent literature reports, silicon nanowire (SiNW) array exhibits not only perfect absorption but also a high surface to volume ratio compared to planar Si. Consequently, the next genera- tion solar cells based on SiNW have attracted a great interest of scientists, engineers, and technology developers due to their potential for higher conversion efciency and being cost-efective compared to the conventional bulk Si solar cell generation [6–10]. Unfortunately, all-inorganic solar cells based on SiNW usually require energy-intensive semicon- ductor processes, including high-temperature thermal difu- sion, thermal annealing of the electrodes, and high-vacuum Hindawi Advances in Materials Science and Engineering Volume 2017, Article ID 2362056, 9 pages https://doi.org/10.1155/2017/2362056