Statistical analyses on inverted perovskite solar cells employing non-fullerene-based small molecule as a cathode interfacial layer.

In this data article, we present the influences of the solvent, concentration, and spin rates of 3,9-bis(2-methylene-(3-(1,1-dicyanomethylene)-indanone))-5,5,11,11-tetrakis(4-hexylphenyl)-dithieno[2,3-d:2',3'-d']-s-indaceno[1,2-b:5,6-b']dithiophene) (ITIC) material on the performances of perovskite solar cells (PSCs). The device parameters such as open-circuit voltage (Voc), short circuit current (Jsc), fill factor (FF), and power conversion efficiency (PCE) were measured with Keithley 2400 source meter unit under 100 mW/cm2 (AM 1.5 G). The data in this article describe the optimization of ITIC-based PSCs and are directly related to our research article "Non-fullerene-based small molecules as an efficient n-type electron transporting layers in inverted organic-inorganic halide perovskite solar cells" (Noh et al., Submitted for publication) [1].

Photo-cross-linked perylene diimide derivative materials as efficient electron transporting layers in inverted polymer solar cells.

We present an efficient and stable interfacial material based on a water-soluble perylene diimide derivative functionalized with ionic and methacrylate groups (abbreviated as PDIM), which can be stabilized by the photo-polymerization of diacrylate groups at both ends of the side chain in the PDIM. The characteristics of the photo-cross-linked PDIM films were examined using absorption spectra, cyclic voltammetry, work function, and surface morphology. The feasibility of the photo-cross-linked PDIM films as a novel electron transporting layer (ETL) in polymer solar cells (PSCs) was also investigated. The PTB7-Th:PC71BM-based PSC using the PDIM as the ETL achieved the excellent power conversion efficiency of 9.44% similar to the conventional polyethylenimine ethoxylated (PEIE) and better than ZnO. Furthermore, the PSC with the PDIM films exhibited a similar lifetime to that of the PEIE-based device. This approach suggests that the photo-cross-linked PDIM film could be regarded as a promising interfacial material for fabricating highly efficient PSCs.

Tin doped indium oxide anodes with artificially controlled nano-scale roughness using segregated Ag nanoparticles for organic solar cells.

Nano-scale surface roughness in transparent ITO films was artificially formed by sputtering a mixed Ag and ITO layer and wet etching of segregated Ag nanoparticles from the surface of the ITO film. Effective removal of self-segregated Ag particles from the grain boundaries and surface of the crystalline ITO film led to a change in only the nano-scale surface morphology of ITO film without changes in the sheet resistance and optical transmittance. A nano-scale rough surface of the ITO film led to an increase in contact area between the hole transport layer and the ITO anode, and eventually increased the hole extraction efficiency in the organic solar cells (OSCs). The heterojunction OSCs fabricated on the ITO anode with a nano-scale surface roughness exhibited a higher power conversion efficiency of 3.320%, than that (2.938%) of OSCs made with the reference ITO/glass. The results here introduce a new method to improve the performance of OSCs by simply modifying the surface morphology of the ITO anodes.

Efficient PEDOT:PSS-Free Polymer Solar Cells with an Easily Accessible Polyacrylonitrile Polymer Material as a Novel Solution-Processable Anode Interfacial Layer.

We demonstrate that an easily accessible polyacrylonitrile (PAN) polymer can efficiently function as a novel solution-processable anode interfacial layer (AIL) to boost the device performances of polymer:fullerene-based solar cells (PSCs). The PAN thin film was simply prepared with spin-coating of a cost-efficient PAN solution dissolved in dimethylformamide on indium tin oxide (ITO), and the thin polymeric interlayer on PSC parameters and stability were systemically investigated. As a result, the cell efficiency of the PSC with PAN was remarkably enhanced compared to the device using bare ITO. Furthermore, with PAN, we finally achieved an excellent power conversion efficiency (PCE) of 6.7% and a very high PSC stability in PTB7:PC71BM systems, which constitute a highly comparable PCE and superior device lifetime relative to those of conventional PSCs with poly(3,4-ethylenedioxythiophene):poly(styrenesulfonate) ( PEDOT: PSS). These results demonstrate that the inexpensive solution-processed PAN polymer can be an attractive PEDOT: PSS alternative and is more powerful for achieving better cell performances and lower cost PSC production.

Fluorine-functionalized and simultaneously reduced graphene oxide as a novel hole transporting layer for highly efficient and stable organic photovoltaic cells.

A one-step reduction and functionalization of graphene oxide (FrGO) was easily achieved using a novel phenylhydrazine-based reductant containing fluorine atoms, which can induce p-type doping due to its high electronegativity. The FrGO-based OPV exhibited a high power conversion efficiency of ∼6.71% and a superior OPV-stability to commercial PEDOT:PSS.

One-step synthesis of carbon nanosheets converted from a polycyclic compound and their direct use as transparent electrodes of ITO-free organic solar cells.

Through a catalyst- and transfer-free process, we fabricated indium tin oxide (ITO)-free organic solar cells (OSCs) using a carbon nanosheet (CNS) with properties similar to graphene. The morphological and electrical properties of the CNS derived from a polymer of intrinsic microporosity-1 (PIM-1), which is mainly composed of several aromatic hydrocarbons and cycloalkanes, can be easily controlled by adjusting the polymer concentration. The CNSs, which are prepared by simple spin-coating and heat-treatment on a quartz substrate, are directly used as the electrodes of ITO-free OSCs, showing a high efficiency of approximately 1.922% under 100 mW cm(-2) illumination and air mass 1.5 G conditions. This catalyst- and transfer-free approach is highly desirable for electrodes in organic electronics.