From chloro to fluoro, expanding the role of aluminum phthalocyanine in organic photovoltaic devices

Abstract

ARTICLE This journal isFluoro aluminum phthalocyanine (F-AlPc) was synthesized by simply heating a DMSO solution of chloro aluminum phthalocyanine (Cl-AlPc) in the presence of CsF, KF or NaF for less than an hour. The resulting F-AlPc has a significant blue shift in the absorbance of ≈ 8 nm in solution and ≈ 130 nm in a solid film compared to Cl-AlPc. Ultraviolet photoelectron spectroscopy (UPS) identified a change in work function and E HOMO of as much as 1 eV between Cl-AlPc and F-AlPc. Our observed change in UPS data, solid-state absorbance and sublimation temperature for F-AlPc further confirms the stacked fluorine bridge solid-state structure for F-AlPc previously described by Kenney et al. Preliminary planar heterojunction (PHJ) organic photovoltaic (OPV) devices were then fabricated using F-AlPc as an electron donating material paired with C 60 and a ternary device including a Cl-AlPc interlayer. Additionally an all AlPc device where F-AlPc functioned as the electron donor and Cl-AlPc as the electron acceptor was fabricated. The EQE plots of the resulting PHJ OPV devices illustrate that an exciton-rectifying layer is present between the Cl-AlPc and F-AlPc layers in the ternary devices as well as the all AlPc device. These results further exemplify that the seemingly minor change from chloride to fluoride in the AlPc structure has significant implications in optoelectronic properties and functionality of AlPc in PHJ OPV devices.

Study of the sensor response of spun metal phthalocyanine films to volatile organic vapors using surface plasmon resonance

“…In contrast to ClAlPc the Q-band of FAlPc film is blue shifted to 656 nm (Fig. 2b) relative to that at 680 nm in the spectrum of its solution [25].…”

“…Chloroaluminum and fluoroaluminum phthalocyanines have been used together with C60 for the fabrication of planar heterojunction and blended organic photovoltaic devices [23][24][25].…”

Degradation of interface between boron subphthalocyanine chloride and fullerene

“…This decrease in E HL caused by the aging is expected to cause a Voc decrease in the corresponding device even kept away from surrounding gases [16][17][18]. In addition, the LUMO level is located at 0.86 and 0.42 eV above the Fermi level for the freshly and aged sample respectively, there is no sign of Fermi level pinning in current studies [19,20].…”

Silicon Phthalocyanines as Acceptor Candidates in Mixed Solution/Evaporation Processed Planar Heterojunction Organic Photovoltaic Devices

“…Bis(3,4,5-trifluorophenoxy) SiPc ((345F) 2 -SiPc) and bis(2,4,6-trifluorophenoxy) SiPc ((246F) 2 -SiPc) were determined to further outperform F 10 -SiPc, with a Voc as high as 0.87 V and a PCE as much as 1.8% [53]. These performances are quite promising for unoptimized devices that are already outperforming other PHJ devices based on well-studied phthalocyanines such as chloro aluminum MPc (Cl-AlPc) [43,46,[55][56][57] or CuPc [43,[58][59][60], further justifying the exploration of SiPcs as thermally evaporated NFAs.…”