The electron transport layer (ETL) plays an important role in high-efficiency perovskite solar cells (PSCs). TiO₂ nanorod (TNR) thin film with outstanding photovoltaic properties is considered as an excellent ETL in the structure of PSCs. To enhance the efficiency of PSCs, ETL heterostructures with anatase TiO₂ nanoparticles (TNPs) and rutile TNRs are fabricated and optimized by two-step hydrothermal process. The maximum efficiency of PSCs based on the ETLs of TiO₂ heterostructures in this study is 14.143%, which is much higher than that of PSC cell with the ETL of pure TNRs (9.361%).

Hypothesis

This study aims to prepare TiO₂ heterostructures with two different polymorphic TiO₂ (anatase TNPs and rutile TNRs) for high-performance PSCs.

Experiments

TiO₂ heterostructures are prepared on conductive FTO substrate by two-step hydrothermal process. Commercial TNPs (P25) are used in different heterostructures for comparison. The structural, morphological characteristics and the current–voltage properties of these ETLs are carefully investigated.

Findings

The enhanced performance of TiO₂ heterostructures-based PSCs is believed to be attributed to the excellent capability of carrier extraction, large surface area, light scattering effect and defect passivation at the ETL/perovskite interface.

中文翻译：

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水热制造的 TiO2 异质结构提高了 MAPbI3 钙钛矿太阳能电池的效率

电子传输层（ETL）在高效钙钛矿太阳能电池（PSC）中发挥着重要作用。具有优异光伏性能的TiO ₂纳米棒(TNR)薄膜被认为是PSCs结构中优异的ETL。为了提高 PSC 的效率，通过两步水热工艺制造和优化具有锐钛矿 TiO _{2纳米颗粒 (TNP) 和金红石 TNR 的 ETL 异质结构。}本研究中基于TiO ₂异质结构ETL的PSCs的最大效率为14.143%，远高于纯TNRs ETL的PSC电池(9.361%)。

假设

本研究旨在制备具有两种不同多晶型 TiO _{2 （锐钛矿 TNP 和金红石 TNR）的 TiO 2}异质结构，用于高性能 PSC。

实验

通过两步水热法在导电FTO衬底上制备TiO _{2异质结构。}商业 TNP (P25) 用于不同的异质结构进行比较。仔细研究了这些 ETL 的结构、形态特征和电流电压特性。

发现

_{基于TiO 2}异质结构的PSCs的增强性能被认为归因于ETL/钙钛矿界面处优异的载流子提取能力、大表面积、光散射效应和缺陷钝化。