Details

Autor(en) / Beteiligte

• Zhang, Yu
• Yu, Wei
• Zhai, Xiong
• Liu, Zhiwei
• Su, Li
• Teng, Xiaoyun
• Fu, Guangsheng

Titel

The effect of oxygen pretreatment at hetero-interface on the photovoltaic properties of MoS2/Si heterojunction solar cells

Ist Teil von

• Journal of alloys and compounds, 2019-09, Vol.803, p.1023-1031

Ort / Verlag

Lausanne: Elsevier B.V

Erscheinungsjahr

2019

Quelle

Alma/SFX Local Collection

Beschreibungen/Notizen

• In this work, we modify the n-type MoS2/p-type Si heterojunction interface by oxygen pretreatment at the initial stage of MoS2 films deposition. Such a facile pretreatment process has effective effect on the defects recombination reduction and band alignment at the MoS2/Si heterojunction interface. By adding the O2 into the sputtering gases and lasting 3-10 s, the oxygen vacancy defects at the hetero-interface significantly decreased and the built-in electric field greatly increased and exceeded 600 mV, which was benefit for reducing defects recombination losses and improving carrier extraction at MoS2/Si interface. Hence, the enhanced MoS2/Si heterojunction solar cells performance (Voc of 243 mV, FF of 58.71 and Jsc of 32.35 mA/cm2) were obtained with the optimized conversion efficiency of 4.62%. While, if the pre-sputtering time was over 20 s, the interface vacancy defects increased instead and the built-in potential was reduced to 582.7 mV, which leads to the poor carrier transport at MoS2/Si interface and adversely affects the cells electrical performance. The results demonstrate that the appropriate oxygen pretreatment could be a new and efficient way to enhance the photovoltaic properties of the MoS2/Si heterojunction solar cells by the interface modification effect. •The MoS2/Si interface issue is modified by the oxygen pretreatment process.•The O2 pretreatment greatly influences the defects distribution and electric field.•The carrier transport mechanism with O2 pretreatment was discussed in detail.•The devices photovoltaic properties are notably enhanced by O2 pretreatment.•The O2 pretreatment is a novel, simple and effective interface modification route.