title: Substituent effects on zinc phthalocyanine derivatives: a theoretical calculation and screening of sensitizer candidates for dye-sensitized solar cells.
abstract: A series of unsymmetrical phthalocyanine sensitizer candidates with different donor and acceptor substituents, namely ZnPcBPh, ZnPcBOPh, ZnPcBtBu, ZnPcBN(Ph)₂, ZnPcBNHPh, ZnPcBNH₂, ZnPcBNHCH₃ and ZnPcBN(CH₃)₂, were designed and calculated using density functional theory (DFT) and time-dependent DFT calculations. The molecular orbital energy levels, the molecular orbital spatial distributions and the electronic absorption spectra of the ZnPcB series molecules were compared with those of TT7 and TT8 to reveal the substituent effects of different donor and acceptor groups on the phthalocyanine compounds and select good sesitizer candidates. The results show that some of these compounds have considerably smaller orbital energy gaps, red-shifted absorption bands and better charge-separated states, causing them to absorb photons in the lower energy region. Several new absorption bands emerge in the 400-600 nm region, which makes it possible for them to become panchromatic sensitizers. This characteristic is superior to the phthalocyanine sensitizers reported previously, including the current record holder, PcS6. The sensitizer candidates screened in the current work are very promising for providing good performance and might even challenge the photon-to-electricity conversion efficiency record of 4.6% for phthalocyanine sensitizers.
authors.affiliation: Shandong Provincial Key Laboratory of Chemical Energy Storage and Novel Cell Technology, School of Chemistry and Chemical Engineering, Liaocheng University, Liaocheng 252059, China.
authors.forename: Linlin
authors.initials: L
authors.lastname: Yang
authors.forename: Lianshun
authors.initials: L
authors.lastname: Guo
authors.forename: Qianqian
authors.initials: Q
authors.lastname: Chen
authors.forename: Huafei
authors.initials: H
authors.lastname: Sun
authors.forename: Hui
authors.initials: H
authors.lastname: Yan
authors.forename: Qinghua
authors.initials: Q
authors.lastname: Zeng
authors.forename: Xianxi
authors.initials: X
authors.lastname: Zhang
authors.forename: Xu
authors.initials: X
authors.lastname: Pan
authors.forename: Songyuan
authors.initials: S
authors.lastname: Dai
mesh_terms: D004396:Coloring Agents / Q000737:chemistry*; D004583:Electrons; D007211:Indoles / Q000737:chemistry*; D054833:Isoindoles; D008958:Models, Molecular; D009942:Organometallic Compounds / Q000737:chemistry*; D017785:Photons; D011789:Quantum Theory; D012993:Solar Energy / Q000706:statistics & numerical data; D055672:Static Electricity; D013472:Sunlight; D013997:Time Factors; D017967:Zinc Compounds
chemical_list: D004396:Coloring Agents; D007211:Indoles; D054833:Isoindoles; D009942:Organometallic Compounds; D017967:Zinc Compounds; C052159:Zn(II)-phthalocyanine; C013647:phthalocyanine