Faculty Profiles - Yamakata Akira

Papers - Yamakata Akira

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Effect of Terminal-Group Halogenation of Naphthalene-Based Nonfullerene Acceptors on Their Film Structure and Photophysical and Photovoltaic Properties Reviewed

Tomokazu Umeyama, Tatsuho Wada, Kensho Igarashi, Kosaku Kato, Akira Yamakata, Taiki Takeyama, Yuji Sakamoto, Yasunari Tamai, Hideo Ohkita, Keiichi Ishida, Tomoyuki Koganezawa, Shunsuke Ohtani, Kazuo Tanaka, Hiroshi Imahori

ACS Applied Energy Materials 4 ( 12 ) 14022 - 14033 2021.12

Publishing type：Research paper (scientific journal) Publisher：American Chemical Society (ACS)

Terminal-group halogenation is an effective strategy for tuning energy levels, improving light-harvesting ability, and enhancing the intermolecular stacking of nonfullerene acceptors (NFAs) for organic photovoltaic (OPV) devices. Understanding the influence of different halogen atoms on their film structure and photophysical and photovoltaic properties is crucial for designing NFAs. To address this issue, three acceptor-donor-acceptor (A-D-A)-type NFAs, named NTTIC-F, NTTIC-Cl, and NTTIC, were designed. All three NFAs consisted of a naphthalene-containing fused-ring as a D core unit and dihalogenated or nonhalogenated 1,1-dicyanomethylene-3-indanone groups as terminal A units. NTTIC-Cl exhibited broadened absorption and downshifted energy levels compared to NTTIC-F and NTTIC. Meanwhile, the singlet exciton lifetimes in solution increased in the order of NTTIC < NTTIC-F < NTTIC-Cl, but these were shortened in the pristine films and rather comparable. From grazing-incidence wide-angle X-ray scattering measurements, the tendency of NTTIC-F < NTTIC < NTTIC-Cl was found for the formation of the face-on-oriented packing structures. To the best of our knowledge, this is the first observation of a change in the molecular orientation of NFAs by the type of the halogenation atom at the terminal A unit. When blended with J71 as a conjugated polymer donor, the NTTIC-Cl-based OPV device showed a higher short-circuit current density (JSC, 20.5 mA cm-2) than the NTTIC-F- and NTTIC-based devices (19.6 and 15.6 mA cm-2, respectively). Overall, the power conversion efficiencies of the NTTIC-F- and NTTIC-Cl-based devices were similar (10.6 and 10.5%, respectively) but higher than that of the NTTIC-based device. The former resulted from the higher open-circuit voltage (VOC, 0.812 V) and fill factor (0.666) of the NTTIC-F-based device than those of the NTTIC-Cl-based device (0.793 V and 0.646, respectively).

DOI： 10.1021/acsaem.1c02816

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Modified SILAR grown ZnO films on p ‐Si(100) with enhanced charge separation for UV light sensing application Reviewed

Jose Presiphil B. Ontolan, Junie Jhon M. Vequizo, Akira Yamakata, Reynaldo M. Vequizo

physica status solidi (a) 218 ( 22 ) 2100363 - 2100363 2021.10

Language：English Publishing type：Research paper (scientific journal) Publisher：Wiley

Herein, the growth of pristine ZnO nanostructures thin film on p-Si(100) by modified successive ionic layer adsorption-reduction method, revealing significant improvement in the charge collection for ultraviolet light detection, is reported. The deposited ZnO exhibits spindle-like and hexagonal structure that grows preferentially along the c-axis. Two-probe electrical measurements validate the rectifying nature of the constructed n-ZnO/p-Si(100), revealing a substantial 11.3-fold increase in photocurrent at room temperature under 375 nm irradiation at +3 V working voltage. The drastic increase in photocurrent is linked to efficient charge separation caused by charge transfer and band bending effects, as indicated by microsecond time-resolved absorption measurements, providing useful information for device development.

DOI： 10.1002/pssa.202100363

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Forward and backward electron transfer on Pt loaded TiO2 photocatalysts under visible-light illumination Reviewed

Naohiro Inoue, Kyohei Shiraki, Kosaku Kato, Shu Ashimura, Masaaki Yoshida, Akira Yamakata

Applied Physics Letters 119 ( 13 ) 133905 - 133905 2021.9

Authorship：Last author,　Corresponding author Language：English Publishing type：Research paper (scientific journal) Publisher：AIP Publishing

The surface plasmon resonance (SPR) effects of metal nanoparticles prove versatile in terms of equipping wideband-gap photocatalysts, such as TiO2, with visible-light responsiveness. In this regard, Au is the most frequently used material for its SPR, but alternative materials are also being actively developed to effectively utilize solar light from the visible to the near-infrared region. In this work, we found that Pt particles loaded on TiO2 were also active in effecting SPR-induced photocatalysis. Time-resolved absorption measurements confirmed that visible-light irradiation induces electron transfer from Pt to TiO2, and the efficiency of this electron injection increases as the wavelength of the incident light decreases from 660 to 450 nm. Observations of the peak shift of the vibrational frequency of adsorbed CO on Pt confirmed that the Fermi level of Pt decreases as the electron transfer from Pt to TiO2 proceeds. These results imply that Pt nanoparticles can act as sensitizers to induce electron transfer from Pt to TiO2, although Pt is a well-known cocatalyst that enhances H-2 evolution by collecting electrons from TiO2. However, as the intensity of the irradiated light increased beyond 50 mW cm(-2), a portion of the Pt particles started to capture the injected electrons from TiO2, suggesting that the electron transfer from one Pt particle to the other Pt particles via the conduction band of TiO2 proceeds under visible light illumination. These opposing roles may be ascribed to the variation in the size of Pt particles as well as density of electrons injected into TiO2.

DOI： 10.1063/5.0065074

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Time-Retrenched Synthesis of BaTaO2N by Localizing an NH3 Delivery System for Visible-Light-Driven Photoelectrochemical Water Oxidation at Neutral pH: Solid-State Reaction or Flux Method? Reviewed

Mirabbos Hojamberdiev, J. Manuel Mora-Hernandez, Ronald Vargas, Akira Yamakata, Kunio Yubuta, Eva Maria Heppke, Leticia M. Torres-Martínez, Katsuya Teshima, Martin Lerch

ACS Applied Energy Materials 4 ( 9 ) 9315 - 9327 2021.9

Language：English Publishing type：Research paper (scientific journal) Publisher：American Chemical Society (ACS)

Among 600 nm class transition-metal oxynitrides, BaTaO2N with a cubic Pm (3) over barm perovskite-type structure is promising for solar water oxidation due to its absorption of visible light up to 660 nm, narrower band gap (E-g = 1.9 eV), appropriate valence band edge position for oxygen evolution, good stability in concentrated alkaline solutions, and nontoxicity. However, high defect density stemmed from long high-temperature ammonolysis limits the separation and transfer efficiency of photogenerated charge carriers in BaTaO2N. Here, a NH3 delivery system is specifically localized just above the synthesis mixture to reduce the synthesis time and defect density of BaTaO2N by a fresh supply of more active nitriding species and minimizing the generation of N-2 and H-2. Particularly, the effects of synthesis temperature (700-950 degrees C), synthesis time (1-8 h), and gas composition are systematically investigated to gain insights into the formation of single-phase BaTaO2N by solid-state reaction and flux method. Time-dependent experiments conducted at 950 degrees C show that single-phase BaTaO2N can be synthesized >= 6 and >= 4 h by solid-state reaction and flux method, respectively, revealing the advantage of the flux method over solid-state reaction in a localized NH3 delivery system. Subsequently, the separation and transfer efficiency and kinetics of photogenerated charge carriers are studied in BaTaO2N samples. Photoelectrochemical studies made it possible to resolve trends during visible-light-induced water oxidation, evidencing the inverse relationship between recombination and charge transfer phenomena. Transient absorption spectroscopy reveals that the dynamics of the photogenerated charge carriers in both types of BaTaO2N samples are different: (i) BaTaO2N synthesized by flux method has a greater number of holes despite the similar number of deeply trapped charge carriers and (ii) solid-state reaction led to the formation of a higher number of free electrons in BaTaO2N. The findings demonstrate the advantage of reducing the transfer distance of active nitriding species to the surface of the synthesis mixture for enhancing the photoelectrochemical water oxidation of BaTaO2N at neutral pH.

DOI： 10.1021/acsaem.1c01539

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Control of the Photocatalytic Activity of Metastable Layered Oxynitride K2LaTa2O6N through Topochemical Transformation of Tuned Oxide Precursors Reviewed

Hiroto Mogi, Kosaku Kato, Shuhei Yasuda, Tomoki Kanazawa, Akinobu Miyoshi, Shunta Nishioka, Takayoshi Oshima, Ya Tang, Toshiyuki Yokoi, Shunsuke Nozawa, Akira Yamakata, Kazuhiko Maeda

Chemistry of Materials 33 ( 16 ) 6443 - 6452 2021.8

Publishing type：Research paper (scientific journal) Publisher：American Chemical Society (ACS)

In the development of oxynitride photocatalysts, thermal ammonolysis of a metal oxide precursor has often been conducted by varying the reaction conditions (e.g., temperatures, reaction times, and ammonia gas flow rates) to obtain high-quality oxynitride particles that efficiently function as photocatalysts. However, this approach may suffer from undesirable changes in the physicochemical properties of the resulting oxynitride, leading to the lowering of the photocatalytic activity. Here, we show that it is possible to control the photocatalytic activity of Ruddlesden-Popper metastable layered oxynitride K2LaTa2O6N, obtained from the Dion-Jacobson phase KLaTa2O7 through a topochemical ammonolysis reaction, by controlling the quality of the KLaTa2O7 template. During the ammonolysis of KLaTa2O7, in the presence of K2CO3, to K2LaTa2O6N, the structural properties (e.g., degree of crystallinity and particle size) of the oxide precursor were replicated in the resulting oxynitride. Namely, the use of KLaTa2O7, possessing a higher degree of crystallinity, led to larger K2LaTa2O6N particles being formed. By increasing the crystallinity of KLaTa2O7, the photocatalytic activity of the resulting K2LaTa2O6N for H2 evolution was improved for reaction in aqueous NaI solution under visible light irradiation. This improvement in performance was due to the longer lifetime of the photogenerated mobile electrons in high-crystallinity K2LaTa2O6N compared with that in the low-crystallinity analogue, as confirmed by femtosecond transient absorption spectroscopy. However, the photocatalytic activity of K2LaTa2O6N derived from well-grown larger KLaTa2O7 particles was an order of magnitude lower than that of the best-performing material. Physicochemical measurements revealed that the large K2LaTa2O6N particles contained a relatively high density of anionic defects on the surface, which shortened the lifetime of the photogenerated charge carriers, leading to lower photocatalytic activity.

DOI： 10.1021/acs.chemmater.1c01726

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Surface Modifications of (ZnSe)0.5(CuGa2.5Se4.25)0.5 to Promote Photocatalytic Z-Scheme Overall Water Splitting Reviewed

Shanshan Chen, Junie Jhon M. Vequizo, Zhenhua Pan, Takashi Hisatomi, Mamiko Nakabayashi, Lihua Lin, Zheng Wang, Kosaku Kato, Akira Yamakata, Naoya Shibata, Tsuyoshi Takata, Taro Yamada, Kazunari Domen

Journal of the American Chemical Society 143 ( 28 ) 10633 - 10641 2021.7

Simultaneously Tuning the Defects and Surface Properties of Ta3N5 Nanoparticles by Mg–Zr Codoping for Significantly Accelerated Photocatalytic H2 Evolution Reviewed

Jiadong Xiao, Junie Jhon M. Vequizo, Takashi Hisatomi, Jabor Rabeah, Mamiko Nakabayashi, Zheng Wang, Qi Xiao, Huihui Li, Zhenhua Pan, Mary Krause, Nick Yin, Gordon Smith, Naoya Shibata, Angelika Brückner, Akira Yamakata, Tsuyoshi Takata, Kazunari Domen

Journal of the American Chemical Society 143 ( 27 ) 10059 - 10064 2021.7

Buckyball as an Electron Donor in a Dyad of C60 and Xanthene Dye Reviewed

Haruka Kano, Kyohei Matsuo, Hironobu Hayashi, Kosaku Kato, Akira Yamakata, Hiroko Yamada, Naoki Aratani

European Journal of Organic Chemistry 2021 ( 23 ) 3377 - 3381 2021.6

Language：English Publishing type：Research paper (scientific journal) Publisher：Wiley

We successfully achieved the synthesis of C-60-xanthlium, X60_NTf2, where fullerene is an electron donor and xanthlium is an electron acceptor. When the precursor compound X60-OH was excited at 550 nm, the C-60 emission was observed at 715 nm. On the other hand, the fluorescence of X60_NTf2 was completely quenched under the same conditions, suggesting that photo-induced intramolecular electron transfer (ET) occurred from the singlet excited state of C-60. The electrochemical measurement proved that the X60_NTf2 is exothermically possible of ET reaction from C-1(60)* to xanthylium to form C-60(.+). Density functional theory (DFT) calculations support the acceptor ability of the xanthylium by showing that the coefficients of the lowest unoccupied molecular orbital (LUMO) were on xanthene moiety. This is a well-arranged model compound to investigate the properties of transiently generated fullerene radical cations.

DOI： 10.1002/ejoc.202100276

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Other Link： https://onlinelibrary.wiley.com/doi/full-xml/10.1002/ejoc.202100276

Titanium Dioxide/Polyvinyl Alcohol/Cork Nanocomposite: A Floating Photocatalyst for the Degradation of Methylene Blue under Irradiation of a Visible Light Source Reviewed

Nurul Hidayah Mohamad Idris, Jayalakshmi Rajakumar, Kuan Yew Cheong, Brendan J. Kennedy, Teruhisa Ohno, Akira Yamakata, Hooi Ling Lee

ACS Omega 6 ( 22 ) 14493 - 14503 2021.6

Language：English Publishing type：Research paper (scientific journal) Publisher：American Chemical Society ({ACS})

Photocatalytic degradation by the titanium dioxide (TiO2) photocatalyst attracts tremendous interest due to its promising strategy to eliminate pollutants from wastewater. The floating photocatalysts are explored as potential candidates for practical wastewater treatment applications that could overcome the drawbacks posed by the suspended TiO2 photocatalysis system. The problem occurs when the powdered TiO2 applied directly into the treated solution will form a slurry, making its reuse become a difficult step after treatment. In this study, the immobilization of titanium dioxide nanoparticles (TiO2 NPs) on the floating substrate (cork) employing polyvinyl alcohol (PVA) as a binder to anchor TiO2 NPs on the surface of the cork was carried out. Characterizations such as Fourier transformer infrared, X-ray diffraction (XRD), ultraviolet-visible spectroscopy (UV-vis), zeta potential, photoluminescence spectroscopy, femtosecond to millisecond time-resolved visible to mid-IR absorption spectroscopy, ion chromatography, and scanning electron microscopy-energy-dispersive X-ray spectroscopy (SEM-EDX) analyses were employed. XRD analysis revealed the formation of anatase-phase TiO2 NPs. The results demonstrated that the crystallite size was 9.36 nm. The band gap energy of TiO2 NPs was determined as 3.0 eV. PL analysis verified that TiO2 NPs possessed a slower recombination rate of electron-hole pairs as compared to anatase TiO2. The result was attributed by the behavior of photogenerated charge carriers on TiO2 NPs, which existed as shallowly trapped electrons that could survive longer than a few milliseconds in this study. Furthermore, SEM-EDX analysis indicated that TiO2 NPs were well distributed on the surface of the cork. At the optimal mole ratio of TiO2/PVA (1:8), the TiO2/PVA/cork floating photocatalyst degraded at 98.43% of methylene blue (MB) under a visible light source which performed better than under sunlight irradiation (77.09% of MB removal) for 120 min. Besides, the mineralization result has measured the presence of sulfate anions after photocatalytic activities, which achieved 86.13% (under a visible light source) and 65.34% (under sunlight). The superior photodegradation performance for MB was mainly controlled by the reactive oxygen species of the superoxide radical (O-center dot(2)-). The degradation kinetics of MB followed the first-order kinetics. Meanwhile, the Langmuir isotherm model was fitted for the adsorption isotherm. The floating photocatalyst presented good reusability, resulting in 78.13% of MB removal efficiency even after five cycles. Our TiO2/PVA/cork floating photocatalyst fabrication and high photocatalytic performance are potentially used in wastewater treatment, especially under visible light irradiation.

DOI： 10.1021/acsomega.1c01458

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(Invited) Core-Shell Double Doping for the Remarkable Photocatalytic Water Splitting on Ga2O3

Akira Yamakata, Junie Jhon M. Vequizo, Kosaku Kato, Yoshihisa Sakata

ECS Meeting Abstracts {MA}2021-01 ( 15 ) 725 - 725 2021.5

Atomically dispersed antimony on carbon nitride for the artificial photosynthesis of hydrogen peroxide Reviewed

Zhenyuan Teng, Qitao Zhang, Hongbin Yang, Kosaku Kato, Wenjuan Yang, Ying-Rui Lu, Sixiao Liu, Chengyin Wang, Akira Yamakata, Chenliang Su, Bin Liu, Teruhisa Ohno

Nature Catalysis 4 ( 5 ) 374 - 384 2021.5

Language：English Publishing type：Research paper (scientific journal) Publisher：Springer Science and Business Media LLC

Artificial photosynthesis offers a promising strategy to produce hydrogen peroxide (H2O2)-an environmentally friendly oxidant and a clean fuel. However, the low activity and selectivity of the two-electron oxygen reduction reaction (ORR) in the photocatalytic process greatly restricts the H2O2 production efficiency. Here we show a robust antimony single-atom photocatalyst (Sb-SAPC, single Sb atoms dispersed on carbon nitride) for the synthesis of H2O2 in a simple water and oxygen mixture under visible light irradiation. An apparent quantum yield of 17.6% at 420 nm together with a solar-to-chemical conversion efficiency of 0.61% for H2O2 synthesis was achieved. On the basis of time-dependent density function theory calculations, isotopic experiments and advanced spectroscopic characterizations, the photocatalytic performance is ascribed to the notably promoted two-electron ORR by forming mu-peroxide at the Sb sites and highly concentrated holes at the neighbouring N atoms. The in situ generated O-2 via water oxidation is rapidly consumed by ORR, leading to boosted overall reaction kinetics.Hydrogen peroxide is an interesting target for artificial photosynthesis, although its actual production via the two-electron oxygen reduction reaction remains limited. Now, a carbon nitride-supported antimony single atom photocatalyst has been developed with a superior performance for this process.

DOI： 10.1038/s41929-021-00605-1

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Other Link： http://www.nature.com/articles/s41929-021-00605-1

A Na-containing Pt cocatalyst for efficient visible-light-induced hydrogen evolution on BaTaO2N Reviewed

Huihui Li, Daling Lu, Shanshan Chen, Takashi Hisatomi, Junie Jhon M. Vequizo, Jiadong Xiao, Zheng Wang, Lihua Lin, Qi Xiao, Yuliang Sun, Yugo Miseki, Kazuhiro Sayama, Akira Yamakata, Tsuyoshi Takata, Kazunari Domen

Journal of Materials Chemistry A 9 ( 24 ) 13851 - 13854 2021.4

Utilization of Perovskite-Type Oxynitride La0.5Sr0.5Ta0.5Ti0.5O2N as an O2-Evolving Photocatalyst in Z-Scheme Water Splitting Reviewed

Hiromu Kumagai, Ryosuke Aoyagi, Kosaku Kato, Akira Yamakata, Masato Kakihana, Hideki Kato

ACS Applied Energy Materials 2021.3

Core–Shell Double Doping of Zn and Ca on β-Ga2O3 Photocatalysts for Remarkable Water Splitting Reviewed

Akira Yamakata, Junie Jhon M. Vequizo, Takafumi Ogawa, Kosaku Kato, Shoya Tsuboi, Naohiro Furutani, Masahiro Ohtsuka, Shunsuke Muto, Akihide Kuwabara, Yoshihisa Sakata

ACS Catalysis 11 ( 4 ) 1911 - 1919 2021.2

Sequential cocatalyst decoration on BaTaO2N towards highly-active Z-scheme water splitting Reviewed

Zheng Wang, Ying Luo, Takashi Hisatomi, Junie Jhon M. Vequizo, Sayaka Suzuki, Shanshan Chen, Mamiko Nakabayashi, Lihua Lin, Zhenhua Pan, Nobuko Kariya, Akira Yamakata, Naoya Shibata, Tsuyoshi Takata, Katsuya Teshima, Kazunari Domen

Nature Communications 12 ( 1 ) 1005 2021.2

Language：English Publishing type：Research paper (scientific journal) Publisher：Springer Science and Business Media LLC

<title>Abstract</title>Oxynitride photocatalysts hold promise for renewable solar hydrogen production via water splitting owing to their intense visible light absorption. Cocatalyst loading is essential for activation of such oxynitride photocatalysts. However, cocatalyst nanoparticles form aggregates and exhibit weak interaction with photocatalysts, which prevents eliciting their intrinsic photocatalytic performance. Here, we demonstrate efficient utilization of photoexcited electrons in a single-crystalline particulate BaTaO₂N photocatalyst prepared with the assistance of RbCl flux for H₂ evolution reactions via sequential decoration of Pt cocatalyst by impregnation-reduction followed by site-selective photodeposition. The Pt-loaded BaTaO₂N photocatalyst evolves H₂ over 100 times more efficiently than before, with an apparent quantum yield of 6.8% at the wavelength of 420 nm, from a methanol aqueous solution, and a solar-to-hydrogen energy conversion efficiency of 0.24% in Z-scheme water splitting. Enabling uniform dispersion and intimate contact of cocatalyst nanoparticles on single-crystalline narrow-bandgap particulate photocatalysts is a key to efficient solar-to-chemical energy conversion.

DOI： 10.1038/s41467-021-21284-3

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Other Link： http://www.nature.com/articles/s41467-021-21284-3

半導体光触媒粒子中の欠陥が及ぼす光励起キャリアの再結合促進と抑制効果 Invited

山方啓, 加藤康作

会報光触媒 64 27 - 36 2021.1

Earth-abundant iron(iii) species serves as a cocatalyst boosting the multielectron reduction of IO3−/I− redox shuttle in Z-scheme photocatalytic water splitting Reviewed

Katsuya Murofushi, Kanta Ogawa, Hajime Suzuki, Ryota Sakamoto, Osamu Tomita, Kosaku Kato, Akira Yamakata, Akinori Saeki, Ryu Abe

Journal of Materials Chemistry A 9 ( 19 ) 11718 - 11725 2021

Cocatalyst engineering of a narrow bandgap Ga-La5Ti2Cu0.9Ag0.1O7S5 photocatalyst towards effectively enhanced water splitting Reviewed

Qi Xiao, Jiadong Xiao, Junie Jhon M. Vequizo, Takashi Hisatomi, Mamiko Nakabayashi, Shanshan Chen, Zhenhua Pan, Lihua Lin, Naoya Shibata, Akira Yamakata, Tsuyoshi Takata, Kazunari Domen

Journal of Materials Chemistry A 9 ( 48 ) 27485 - 27492 2021

Atomically dispersed antimony on carbon nitride for the artificial photosynthesis of hydrogen peroxide (vol 4, pg 374, 2021)

Akira Yamakata

Nature Catalysis 2021

Heavy Metal Effects on the Photovoltaic Properties of Metallocorroles in Dye-Sensitized Solar Cells Reviewed

Tomohiro Higashino, Yuma Kurumisawa, Abraham B. Alemayehu, Rune F. Einrem, Debashis Sahu, Daniel Packwood, Kosaku Kato, Akira Yamakata, Abhik Ghosh, Hiroshi Imahori

ACS Applied Energy Materials 3 ( 12 ) 12460 - 12467 2020.12

Authorship：Corresponding author Language：English Publishing type：Research paper (scientific journal) Publisher：American Chemical Society ({ACS})

Finding strategies for effective charge separation is a prerequisite for realizing efficient solar energy conversion in photovoltaic and photocatalytic devices. Porphyrinoids, including porphyrins and related macrocycles such as phthalocyanines and corroles, are versatile ligands that can accommodate a single metal atom for most metal ions, and their photophysical and electro-chemical properties can be tuned by the metal atom in the cavity. Herein, we evaluated the photovoltaic properties of the dyesensitized solar cells (DSSCs) based on Au-III-, (ReO)-O-V-, and (OsN)-N-VI-corroles with COOH anchoring groups at the para- and meta-positions of the meso-phenyl groups. The DSSCs based on Au-III-corroles exhibited a power conversion efficiency (PCE) of 4.2%, which is remarkably higher than those for the (ReO)-O-V- and (OsN)-N-VI-corroles. Femtosecond time-resolved transient absorption measurements have shown that the electron injection from the excited singlet state competes with intersystem crossing, and that intersystem crossing for Au-III-corroles is slower than those for ReVO- and (OsN)-N-VI-corroles. Consequently, the high incident photon-to-current efficiencies and resultant short-circuit current densities and PCEs for Au-III-corroles are attributed to the high electron injection efficiencies owing to the slower intersystem crossing than ReVO- and (OsN)-N-VI-corroles. In addition, the higher PCE for a Au-III-corrole with a meta-COOH group (4.2%) as opposed to a para-COOH group (3.4%) is explained by the stronger Au-TiO2 interactions supported by XPS measurements and theoretical calculations. These results imply that both the substituents and the metal ion have a large influence on the photovoltaic performances. Overall, DSSCs based on the Au-III-corroles were found to exhibit the highest photovoltaic performance among corrole-based DSSCs.

DOI： 10.1021/acsaem.0c02427

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