Title: Efficient Silicon Solar Cells with Carrier-selective and Dopant-free Heterojunctions
Speaker: Dr. Pingqi Gao Institute of Materials Technology and Engineering, Chinese Academy of Sciences
Time: 2:00-3:30pm, June 30

Venue: Admin. Building Room 108-109

Abstract: Enormous amount of effort and resources have been invested on seeking new generation photovoltaic (PV) technologies, which can reach both materials saving and procedures simplification. Compared with commercially available crystalline silicon (c-Si) solar cells achieved by doping technique in near-surface regions, heterojunction solar cells consisted with high-workfunction layers, such as MoOx (x<3), poly(3,4-ethylenedioxythiophene):poly(styrenesulfonate) (PEDOT:PSS), etc. and n-type c-Si provide a promising new concept with dopant-free and carrier-selective heterocontacts. In combination with advanced light-trapping structures on c-Si surface, the simplified heterojunction of hybrid PEDOT:PSS/c-Si can achieve power conversion efficiencies (PCE) approaching 13%. For this heterojunction solar cell, interface engineering is crucial to promote the performance of photovoltaic devices due to the abilities to optimize the separation of carries and minimize the interfacial recombination. Here, efficient PEDOT:PSS/c-Si heterojunction solar cells with periodic pyramid configurations are present and physical method is firstly used to minimal the interfacial recombination at PEDOT:PSS and c-Si interface. Benefit from the acting force on PEDOT:PSS, perfect interfacial contact is achieved on nanostructured c-Si surface, resulting in an open-circuit voltage beyond 650 mV for this heterojunction solar cell and finally a record PCE over 16%. These results enable a viable route for high-performance and dopant-free heterojunctions solar cell.

Personal profile: Gao Pingqi, PhD, researcher, doctoral tutor, Chinese Academy of Sciences Ningbo Institute of Materials Technology and Engineering. He graduated from Lanzhou University, Department of Physics, Department of Microelectronics, 2007-2011 in Nanyang Technological University, Singapore Institute of Electrical and Electronic Engineering Institute of Microelectronics Center to do joint training, postdoctoral research doctorate, 2010, graduated from Lanzhou University, Condensed Matter Physics. After returning to a former central enterprises under the new energy company deputy chief engineer, responsible for solar cell technology research and development and industrialization of the work. January 2013 joined the Chinese Academy of Sciences, Ningbo Institute of Materials, "Spring Bud" associate researcher, and with the end of 2015 exceptional promotion to a researcher, research work focused on solar cells, new semiconductor materials synthesis, efficient low-cost solar cell device preparation and flexible electronic circuits And so on, currently in Adv. Energy. Mat