【公開日：2025.06.10】【最終更新日：2025.03.24】
課題データ / Project Data
課題番号 / Project Issue Number
24BA0060
利用課題名 / Title
Performance Enhancement of Sn-Based Perovskite Solar Cells
利用した実施機関 / Support Institute
筑波大学 / Tsukuba Univ.
機関外・機関内の利用 / External or Internal Use
外部利用/External Use
技術領域 / Technology Area
【横断技術領域 / Cross-Technology Area】（主 / Main）計測・分析/Advanced Characterization（副 / Sub）-
【重要技術領域 / Important Technology Area】（主 / Main）革新的なエネルギー変換を可能とするマテリアル/Materials enabling innovative energy conversion（副 / Sub）-
キーワード / Keywords
発電関連材料/ Materials for power generation,太陽電池/ Solar cell,電子分光/ Electron spectroscopy
利用者と利用形態 / User and Support Type
利用者名（課題申請者）/ User Name (Project Applicant)
ISLAM Ashraful
所属名 / Affiliation
物質・材料研究機構
共同利用者氏名 / Names of Collaborators in Other Institutes Than Hub and Spoke Institutes
KAYESH Md Emrul
ARIM実施機関支援担当者 / Names of Collaborators in The Hub and Spoke Institutes
利用形態 / Support Type
（主 / Main）機器利用/Equipment Utilization（副 / Sub）,技術補助/Technical Assistance
利用した主な設備 / Equipment Used in This Project
BA-026：多機能走査型X線光電子分光分析装置（XPS/UPS）
BA-006：走査型プローブ顕微鏡
報告書データ / Report
概要（目的・用途・実施内容）/ Abstract (Aim, Use Applications and Contents)
Perovskite
solar cells (PSCs) have recently garnered significant attention due to their
extraordinary power conversion efficiency (PCE) enhancement. The toxicity of
lead significantly obstructs the widespread application of PSCs. To address
this toxicity issue, we are focusing on Sn-based PSCs. The highest reported PCE
for Sn-PSCs is under 16%, significantly lower than that of Pb-PSCs. One
factor is the propensity of the facial structure to oxidize from Sn2+
to Sn4+ and the rapid crystallization rate of perovskite. In our
research, we are focused on regulating Sn2+ oxidation and forming
uniform electrostatic potential surfaces for smooth charge extraction. The
surface of Sn-based perovskite films is susceptible to oxidation due to free Sn2+.
To
prevent the oxidation of Sn2+ and form a uniform electrostatic
potential perovskite surface, we performed surface treatment with tailored 2D
perovskite materials. These 2D perovskite materials not only coordinate with
free Sn2+ to prevent Sn oxidation but also create a uniform
electrostatic potential perovskite surface for efficient charge extraction by
the charge transport layer (CTL).
After
performing the surface treatment with tailored 2D perovskite materials we had
to characterize the perovskite film to know the change in properties after the
surface treatment.
実験 / Experimental
We used X-ray photoelectron spectroscopy (XPS) for surface composition and atomic forced microscopy (AFM/KFPM) for contact potential difference (CPD). By using XPS we have obtained the ratio of Sn2+/Sn4+ for pristine (without surface treatment) and surface-treated perovskite films and know the presence of trace elements on the perovskite surface such as sulfur, nitrogen, etc. From the KFPM measurement, we have known the change in CPD between pristine and surface-treated perovskite films. The measurement of CPD is important to ensure smooth charge transfer from perovskite to CTL. After analyzing the XPS data, we found that the Sn2+ content in the surface-treated perovskite film reduced by up to 8% which was consistent with our device results. The KFPM results also indicate that the surface treatment Sn-perovskite with tailored 2D perovskite materials formed uniform electrostatic potential throughout the film in comparison to the pristine films. This result is also consistent with our device results. However, the resolution of the CPD images is not good but average.
結果と考察 / Results and Discussion
To confirm the coordination between the
surface-treated additive and free Sn2+, we performed XPS measurement
to determine the exact pick positions for Sn2+, Sn4+, and
I- ions. The picks of Sn2+ and Sn4+ are very close
together that why we needed to deconvolute the Sn pick into Sn2+ and
Sn4+. After deconvoluting the Sn picks, we observed the Sn2+
picks move to lower binding energy for the surface-treated film as compared
with the pristine film. This result indicates the effective coordination
between free Sn2+ and surface-treated additive molecules. This type
of coordination effectively hinders the oxidation of free Sn2+ at
the surface of perovskite film. From the XPS results, we also observed that the
concentration of Sn4+ reduced from 18% (pristine) to 8%
(surface-treated). The lower the Sn4+ concentration higher the
optimum photovoltaic properties of Sn-perovskite film. These results are also
consistent with the device's performance.
The Sn-perovskite film’s surface suffers
from nonuniform electrostatic potential which hinders the smooth charge
extraction. To make uniform electrostatic potential at the Sn-perovskite
surface, we perform the surface treatment with tailored 2D perovskite
materials. From the KFPM result, we observed a lower CPD all over the
surface-treated films as compared with the pristine films. This may be due to
the passivation of additive molecules. These results were also consistent with
the device's performance.
図・表・数式 / Figures, Tables and Equations
その他・特記事項（参考文献・謝辞等） / Remarks(References and Acknowledgements)
成果発表・成果利用 / Publication and Patents
論文・プロシーディング（DOIのあるもの） / DOI (Publication and Proceedings)
口頭発表、ポスター発表および、その他の論文 / Oral Presentations etc.
特許 / Patents
特許出願件数 / Number of Patent Applications：0件
特許登録件数 / Number of Registered Patents：0件