The electron transport layer(ETL) plays an important role in planar heterojunction perovskite solar cell(PSCs),by affecting the light-harvesting, electron injection and transportation processes, and especially the crystallization of perovskite absorber. In this work, we utilized a commercial TKD-TiO_2 nanoparticle with a small diameter of 6 nm for the first time to prepare a compact ETL by spin coating. The packing of small-size particles endowed TKD-TiO_2 ETL an appropriate surface-wettability, which is beneficial to the crystallization of perovskite deposited via solution-processed method. The uniform and high-transmittance TKD-TiO_2 films were successfully incorporated into PSCs as ETLs. Further careful optimization of ETL thickness gave birth to a highest power conversion efficiency of 11.0%, which was much higher than that of PSC using an ETL with the same thickness made by spray pyrolysis. This TKD-TiO_2 provided a universal solar material suitable for the further large-scale production of PSCs. The excellent morphology and the convenient preparation method of TKD-TiO_2 film gave it an extensive application in photovoltaic devices.
Peng ChenYinglin WangMeiqi WangXintong ZhangLingling WangYichun Liu
TiO2 heterojunction with different TiO2 phases has been widely adopted for enhanced photocatalysis.Therein,a less common anatase/bronze TiOz heterojunction,also named as anatase/TiO2(B)heterojunction,has recently drawn increasing interest.In this review,the structural advantages of anatase/bronze TiO2 heterojunction for enhanced photocatalysis is highlighted in terms of less lattice mismatch and better charge separation at the interface.Besides photocatalysis,the anatase/bronze TiO2 heterojunction is proven a promising candidate for heat-assisted photocatalysis,named as photothermal catalysis.Further,the anatase/bronze TiO2 heterojunction can serve as a good model to evaluate the strategy for improved photocatalysis and even photothermal catalysis.Herein,the recent attempts on boosting the photocatalytic and photothermal catalytic performance of anatase/bronze TiO2 heterojunction are summarized.It is expected that this review would arouse renewed interest for revisiting TiO2 heterojunction in photocatalysis,photothermal catalysis and other advanced photocatalysis.