Perpustakaan Digital ITB

The use of solution-processed hole transporting layers(HTLs), without the need of added dopants, is important for theadvancement of high-performance perovskite solar cells (PSCs). Here, asmall molecule,N,N?-bis(naphthalen-1-yl)-N,N?-bis(phenyl)benzidine(NPB), is utilized as an efficient, dopant-free HTL in inverted PSCs toreplace the commonly used poly(3,4-ethylenedioxythiophene):poly-(styrenesulfonic acid) (PEDOT:PSS). A best power conversion efficiency(PCE) of 19.96% is realized when using NPB as the HTL, along with ashort circuit current density (JSC) of 22.92 mA/cm2, an open circuitvoltage (VOC) of 1.11 V, and afill factor (FF) of 78.4%. ThisVOCis oneof the highest obtained values in CH3NH3PbI3-based inverted PSCs andis comparable to devices with regular structure. The use of NPB as theHTL produced perovskitefilms with larger grain size and highercrystallinity than obtained with PEDOT:PSS. As a result of this improvedperovskitefilm quality, recombination loss decreased dramatically, boostingJSCvalues. Furthermore, due to reducedrecombination and better energy level alignment arising from the use of NPB, theVOCin the NPB-containing device increasedconsiderably. In addition, NPB-based PSCs exhibited longer term stability as a result of the hydrophobicity of NPB.