title: Tuning indium tin oxide work function with solution-processed alkali carbonate interfacial layers for high-efficiency inverted organic photovoltaic cells.
abstract: Selective electron collection by an interfacial layer modified indium tin oxide cathode is critically important for achieving high-efficiency inverted structure organic photovoltaic (OPV) cells. Here, we demonstrate that solution-processed alkali carbonates, such as Li2CO3, Na2CO3, K2CO3, Rb2CO3, Cs2CO3, are good interfacial layer materials. Both carbonate concentration and annealing conditions can affect cathode work function and surface roughness. By proper optimization, different alkali carbonates can be almost equally effective as the cathode interfacial layer. Furthermore, good device performance can be achieved at a low annealing temperature (<50 ° C), which allows for potential applications in solution-processed inverted OPV cells on plastic substrates. This work indicates that alkali carbonates, not just cesium carbonate, are valid choices as the cathode interlayer in inverted OPV devices.
authors.affiliation: i-LAB, Suzhou Institute of Nano-Tech and Nano-Bionics, Chinese Academy of Sciences, Suzhou 215123, People's Republic of China. Nano Science and Technology Institute, University of Science and Technology of China, Suzhou 215123, People's Republic of China.
authors.forename: Fei
authors.initials: F
authors.lastname: Chen
authors.forename: Qi
authors.initials: Q
authors.lastname: Chen
authors.forename: Lin
authors.initials: L
authors.lastname: Mao
authors.forename: Yixin
authors.initials: Y
authors.lastname: Wang
authors.forename: Xun
authors.initials: X
authors.lastname: Huang
authors.forename: Wei
authors.initials: W
authors.lastname: Lu
authors.forename: Bing
authors.initials: B
authors.lastname: Wang
authors.forename: Liwei
authors.initials: L
authors.lastname: Chen