Crystallization process determines the quality of perovskite films and the performances of resultant perovskite solar cells(PSCs).Dimethylamine oxalate has been proven as a multifunctional modulator,and is explored as...Crystallization process determines the quality of perovskite films and the performances of resultant perovskite solar cells(PSCs).Dimethylamine oxalate has been proven as a multifunctional modulator,and is explored as an efficient additive in manipulating the crystallization process of CsPbI_(3) perovskite films.On one hand,oxalate serves as the precipitator that facilitates the nucleation process of intermediate.The larger size of intermediate is conductive to the larger size and smaller grain boundaries of resultant perovskite.On the other hand,in subsequent annealing process,the phase conversion and growth process of transient perovskite can be decelerated due to the strong interactions of oxalate with both dimethylamine cation(DMA^(+))and Pb^(2+).Due to the optimized crystallization kinetics,the morphology and quality of CsPbI_(3) perovskite films are comprehensively improved with lower defect concentrations,and charge recombination loss is effectively suppressed.Benefiting from the optimized crystal quality of perovskite films,the carbon electrode-based CsPbI_(3) PSCs exhibit a champion efficiency of 18.48%.This represents one of the highest levels among all hole transport layer-free inorganic perovskite solar cells.展开更多
In the construction of high performance planar perovskite solar cells(PSCs),the modification of compact TiO_(2) layer and engineering of perovskite/TiO_(2) interfaces are essential for efficient electron transfer and ...In the construction of high performance planar perovskite solar cells(PSCs),the modification of compact TiO_(2) layer and engineering of perovskite/TiO_(2) interfaces are essential for efficient electron transfer and retarded charge recombination loss.In this work,a facile and effective strategy is developed to modify the surface of compact TiO_(2) layer by TiCl_(4)-TiCl_(3) mixture treatment.Compared with conventional sole TiCl_(4),the TiCl_(4)-TiCl_(3) treatment takes the advantage of accelerated and controlled hydrolysis of TiCl_(3),therefore TiO_(2) with dominating anatase phase and moderate roughness is obtained to facilitate the growth of CsPbI_(2) Br perovskite layer with high quality.Furthermore,the oxidation-driven hydrolysis of TiCl_(3) component results in surface Cl doping that facilitates interfacial electron transfer with retarded recombination loss.The average power conversion efficiency(PCE) of carbon-based CsPbI_(2) Br planar PSCs based on TiCl_(4)-TiCl_(3) treatment increases to 14.18% from the intial 13.04% based on conventional sole TiCl_(4) treatment.The champion PSC exhibits a PCE of 14.46%(V_(oc)=1.28 V,J_(sc)=14.21 mA/cm^(2),and FF=0.794),which is one of the highest PCEs for carbon-based CsPbI_(2) Br PSCs.展开更多
基金supported by the National Natural Science Foundation of China(Nos.U21A20310,22278164,22122805,22308112)the Science and Technology Program of Guangzhou,China(No.2023A04J0665)China Postdoctoral Science Foundation(No.2023M741214)。
文摘Crystallization process determines the quality of perovskite films and the performances of resultant perovskite solar cells(PSCs).Dimethylamine oxalate has been proven as a multifunctional modulator,and is explored as an efficient additive in manipulating the crystallization process of CsPbI_(3) perovskite films.On one hand,oxalate serves as the precipitator that facilitates the nucleation process of intermediate.The larger size of intermediate is conductive to the larger size and smaller grain boundaries of resultant perovskite.On the other hand,in subsequent annealing process,the phase conversion and growth process of transient perovskite can be decelerated due to the strong interactions of oxalate with both dimethylamine cation(DMA^(+))and Pb^(2+).Due to the optimized crystallization kinetics,the morphology and quality of CsPbI_(3) perovskite films are comprehensively improved with lower defect concentrations,and charge recombination loss is effectively suppressed.Benefiting from the optimized crystal quality of perovskite films,the carbon electrode-based CsPbI_(3) PSCs exhibit a champion efficiency of 18.48%.This represents one of the highest levels among all hole transport layer-free inorganic perovskite solar cells.
基金supported by the National Natural Science Foundation of China (51732004, 21805093, 21975083, 2170307122075090)the Science and Technology Program of Guangzhou,China (201904010178)。
文摘In the construction of high performance planar perovskite solar cells(PSCs),the modification of compact TiO_(2) layer and engineering of perovskite/TiO_(2) interfaces are essential for efficient electron transfer and retarded charge recombination loss.In this work,a facile and effective strategy is developed to modify the surface of compact TiO_(2) layer by TiCl_(4)-TiCl_(3) mixture treatment.Compared with conventional sole TiCl_(4),the TiCl_(4)-TiCl_(3) treatment takes the advantage of accelerated and controlled hydrolysis of TiCl_(3),therefore TiO_(2) with dominating anatase phase and moderate roughness is obtained to facilitate the growth of CsPbI_(2) Br perovskite layer with high quality.Furthermore,the oxidation-driven hydrolysis of TiCl_(3) component results in surface Cl doping that facilitates interfacial electron transfer with retarded recombination loss.The average power conversion efficiency(PCE) of carbon-based CsPbI_(2) Br planar PSCs based on TiCl_(4)-TiCl_(3) treatment increases to 14.18% from the intial 13.04% based on conventional sole TiCl_(4) treatment.The champion PSC exhibits a PCE of 14.46%(V_(oc)=1.28 V,J_(sc)=14.21 mA/cm^(2),and FF=0.794),which is one of the highest PCEs for carbon-based CsPbI_(2) Br PSCs.
基金supported by Guangdong Laboratory for Lingnan Modern Agriculture(NZ2021030)the National Natural Science Foundation of China(21975083,U21A20310,51732004,22122805,and 22075090)。
