bluuebunny/crossref_metadata_2025_split huggingface dataset:
(Invited) Scalable Fabrication of Moisture Resistant Perovksite Solar Cells
Authors: Sunkara Mahendra Kumar 
Published: February 2020

Organic-inorganic halide perovskites have created a breakthrough in the field of solar cells because of their low cost, low temperature processibility and excellent optoelectronic properties. However, the instability of organic-inorganic halide perovskites to moisture is currently a huge challenge in the field of perovskite solar cells and needs to be addressed to translate the perovskite technology from the laboratory bench to large scale industrial practice. Currently, all the lab scale perovskite cells are fabricated in controlled glove box atmosphere with less than 1 % relative humidity to prevent their deterioration under moisture.
In this work, a novel concept of protecting the perovskite using a highly conductive composite of a layered material and a hole transporting polymer is presented.1 The excellent charge transport properties of the composite coating allow the use of thick coating on the perovskite, creating extremely high length scales for moisture diffusion through composite. The composite coating developed in our work, could be extended to lead-free organometallic perovskites that are both moisture and oxygen sensitive. In addition, we also present our results on our lamination approach for scalable assembly perovskite electrodes.2 The deposition of gold as a counter electrode for the lab scale perovskite cells is usually performed by thermal evaporation in a bell jar evaporator. This process is time consuming, energy intensive and not viable to scale up. Our approach involving lamination of individual electrodes, enables a much facile low cost process for fabricating perovskite solar cells.
Our results and observation on polymer composites as protective coatings for perovskite and on laminating electrodes show high promise for the scalability and low cost fabrication of perovskite cells under atmospheric conditions (60 -70 % relative humidity).

References

Rajamanickam, N., Vendra, V.K., Kumari, S., Lavery, B.W., Ramachandran, K., Druffel, T., Sunkara, M.K. Moisture resistant methyl ammonium lead iodide perovskite solar cells. Submitted 2014.

Vendra, V.K., Kumari, S., Lavery, B.W., Rajamanickam, N., Druffel, T., Sunkara, M.K. Atmospheric roll to roll processing in perovskite solar cells. Submitted 2014
(Invited) Visible to Near-IR Nanoplasmonics in Inorganic Nanoparticles
Authors: Teranishi Toshiharu 
Published: February 2020

A very important aspect of localized surface plasmons is the localization of an enhanced electromagnetic field around the NPs with very high spatial resolution (subwavelength) as well as the generation of hot electrons [1-6]. Here I present the unique plasmonic properties of non-stoichiometric copper sulfide (Cu7S4) nanodisks in the near IR (NIR) region by changing the hole density, structural anisotropy, and assembled structure [5-8]. As an example of plasmon-induced hot electron application, the visible to near-IR plasmon-enhanced catalytic activity of Pd hexagonal nanoplates for the Suzuki coupling reactions is also presented [9].
[1] Teranishi, T. et al. J. Mater. Chem.
2011, 21, 10238-10242. (Highlight)
[2] Yang, S.; Teranishi, T.; Gwo, S. et al. Nano Lett.
2010, 10, 632-637.
[3] He, C.-L.; Teranishi, T.; Gwo, S. et al. ACS Nano
2011, 5, 8223-8229.
[4] Li, C.; Sun, L.; Sun, Y.; Teranishi, T. Chem. Mater.
2013, 25, 2580-2590.
[5] Kanehara, M.; Teranishi T. et al. J. Am. Chem. Soc.
2009, 131, 17736-17737. (Spotlight)
[6] Furube, A.; Teranishi T. et al. Angew. Chem. Int. Ed.
2012,51, 2640-2642.
[7] Kanehara, M.; Teranishi, T. et al. Chem. Eur. J.
2012, 18, 9230-9238. (Frontispiece)
[8] Chen, L.; Teranishi, T. et al., submitted.
[9] Trinh, T. T.; Teranishi, T. et al., submitted.
(Invited) A Unique Architecture Based on 1D Semiconductor/ Reduced Graphene Oxide/ Chalcogenide with Multifunctional Properties
Authors: Subramanian Vaidyanathan 
Published: February 2020

Photoelectrochemical processes involving 1D architectures are reveling interesting optical and electronic properties that can often exceed the performance of their 0D counterparts. A unique hetero-structured optoelectronic material (HOM), consisting of a reduced graphene oxide (RGO) layer with spatially distributed CdS, suspended by zinc oxide (ZnO) nanorods, is presented. The key features of this HOM are the assembly of the components in a manner so as to realize an effective integration between the constituents and the ability to modify the electronic properties of the RGO. For the first time, the location of RGO (as a suspended layer) along with the tuning of its charge transport properties (n-/p- type) and its influence on the photo(electro)chemical processes has been examined systematically using this ZnO/RGO/CdS HOM as a case study.
The n-RGO interlayer facilitates >100% increase in the photocurrent density and 25% increase in the photodegradation of a dye, demonstrating its multifunctionality. At 3.2 mA/cm2, this HOM architecture helps to achieve the highest photocurrent density utilizing ZnO, RGO, and CdS as building blocks in any form. The work assumes significance, as (i) other one dimensional (1D) oxides/chalcogenides or 1D oxides/dyes may be designed with similar architectures, (ii) HOMs with tunable optical absorbance and charge transport properties could be realized, and (iii) related application areas (e.g., sensing or solar fuel generation) should be greatly benefited.
Porphycene-Diketopyrrolopyrrole Conjugates As p-Type Organic Solar Cell Materials
Authors: Kuzuhara Daiki , Okabe Takuya , Suzuki Mitsuharu , Aratani Naoki , Yamada Hiroko 
Published: February 2020

Porphycene is a constitutional isomer of porphyrin. Porphycene has a lower LUMO level and smaller HOMO-LUMO difference than porphyrin since its molecular symmetry is lower than that of porphyrin.
1
These properties have allowed us to explore the possible applications of porphycenes in the fields of photodynamic therapy (PDT), photoinactivation of viruses and bacteria, protein mimicry, nonlinear optics, and catalysis. Recently, we have focused on the porphycene using as the semiconducting materials for organic solar cell (OSC). OSC materials require for the absorption covering the visible to NIR regions and appropriate HOMO and LUMO energy levels. In this presentation, we have designed, synthesized and properties of the porphycene–diketopyrropyrrole conjugate (Pc–DPP) though ethynyl linkages for the OSC as p-type materials. The absorption of the DPP unit appears at around 450-550 nm, while porphycene has an absorption valley around 400-550 nm. The combination of DPP and porphycene via ethynyl linkages is expected to generate absorption covering the visible to NIR regions of the spectrum. We have measured absorption spectra of Pc–­DPP and 2,7,12,17-tetrahexylporphycene (THPc) as reference compound in thin-film on glass substrate. THPc has strong Soret band at 400 nm and Q-bands around 550 to 700 nm. On the other hand, as the result of the connection with porphycene and DPP units, Pc–DPP has broad absorption covering the visible to near in-fared regions. Based on these optical characters, we have fabricated bulk heterojunction (BHJ) OSC by solution process with Pc–DPP as a p-type material and PC61BM as an n-type material. The active layer of the mixture of Pc–DPP and PC61BM with 0.1% 1,8-diiodooctane containing chloroform was deposited on the PEDOT:PSS-treated ITO substrate by spin coating and then calcium and aluminum electrode were deposited on the active layer by vacuum process. After optimized the device conditions, we achieved the PCEs of 1.4% (J
sc = 4.88 mA cm-2, V
oc = 0.81 V and FF = 0.37). We will also report the evaluations of film structures of these devices by AFM and XRD measurements.
Efficient Combination of Porphyrins and Thiophene Derivatives for Photovoltaics
Authors: Langa Fernando , de la Cruz Pilar , Arrechea Susana , Aljarilla Ana 
Published: February 2020

Mimicking the photosynthesis, where chlorophylls absorb light for energy conversion, porphyrin and their derivatives can be suited as panchromatic photosensitizers being excellent building blocks in the construction of molecular architectures for light harvesting. Thus, porphyrins are among the most significant types of sensitizers for Dye Sensitized Solar cells (DSSCs) showing record breaking performances as high as 13%. However, utilization of porphyrins as active material in solution-processed BHJ has been scarce despite the natural tendency of porphyrins to form aggregates by π-π stacking and then favour intermolecular interactions and, consequently, the efficiency of the device.
In this lecture, we will present the synthesis and characterization of novel Porphyrin derivatives where the porphyrin is covalently linked to different thiophene-based moieties. The photophysical properties of these novel conjugates, as well as their application in photovoltaic devices (DSSCs and BHJ OPVs) will also be presented.
Charge Generation, Regeneration and Recombination in Di-Chromophoric Carbazole-Thiophene-Porphyrin-Sensitised Solar Cells
Authors: Mozer Attila Janos 
Published: February 2020

Porphyrins are among the best performing dyes for their application in dye-sensitized solar cells. However, light harvesting efficiencies between the Soret and Q bands of most simple porphyrins are limited, especially when thin electrodes or electrodes with low surface area are used. Filling the absorption gap is an important objective to further enhance their efficiency, in addition to extending their absorption band edge to better match the solar spectrum.
In this work, the absorption gap between the Soret and Q bands is filled using a multi-chromophoric approach following the synthetic strategy we have developed earlier (J. Am. Chem. Soc.
2009, 131, 15621-15623; J. Mater. Chem. A
2014, 2, 16963-16977). Three new porphyrin dyes with carbazole-fused thiophene chromophores attached to the porphyrin core using a non-conjugated phenylethenyl linker are synthesised. When attached to TiO2, an almost complete filling of the absorption gap within the 450 nm to 500 nm is achieved, which leads to doubling of the short circuit current density using the Co2+ / Co3+ electrolyte. In addition, the electron lifetime has significantly improved contributing to increased power conversion efficiency of 4.7%. Particularly significant result is the nearly 100% absorbed photon to collected electron efficiency at wavelengths dominated by the side chain absorption, suggesting the promise of the multi-chromophoric dye design using the non-conjugated approach.
Detailed transient absorption and spectro-electrochemical investigations reveal a significant acceleration of dye cation regeneration kinetics in carbazole-porphyrin dyads attached to TiO2. This is attributed to a picosecond to microsecond intramolecular hole transfer from the porphyrin cation to carbazole, followed by a fast reduction of the carbazole cation by the electron donor redox mediator dissolved in the electrolyte. Such increase of the turnover rates without affecting the final electrochemical potential of the photo-generated species is promising for a variety of photo-electrochemical energy conversion processes, including solar cells and solar fuels.
Synergistic Interaction of Phthalocyanines and Semiconductor Quantum Dots for Advanced Co-Sensitized Solar Cells
Authors: Sastre-Santos Angela , Blas-Ferrando Vicente M. , Ortiz Javier , Sánchez Rafael S. , González-Pedro Maria Victoria , Fernández-Lázaro Fernando , Mora-Seró Iván 
Published: February 2020

Quantum dots (QDs) are among potential key players in the next generation of photovoltaic devices [1] due to their low-cost solution-phase processability, large absorption cross sections, a spectrally tunable absorption onset (achieved via the quantum size effect), and enhanced multiple exciton generation or carrier multiplication.[2] After the first report on a certified QD solar cell, a remarkable progress has been reached just in a couple of years obtaining certified power conversion efficiencies (PCEs) approaching 9%.[3]
On the other hand, phthalocyanines (Pcs) are outstanding dye candidates in dye sensitized solar cells (DSSCs) due to their high extinction coefficient in the infrared spectral region and to their high thermal and chemical stabilities.[4] Pcs incorporated in DSSCs have achieved PCEs as high as 6.4 %,[5] still far away of the 12.75% PCE obtained by porphyrins, their closest relatives. An elegant strategy to improve the light-harvesting ability of the Pcs is the binding, either covalent or supramolecular, to a complementary chromophore, such as QDs, able to undergo efficient electron transfer to the charge injecting system. However, the chemical combination of Pc rings to QDs has hardly been explored probably due to the difficulties to synthesize Pcs with the adequate anchoring groups.
Herein, we will report our more recent results related with the synthesis of different unsymmetrically substituted phthalocyanines containing sulphur atom (see Figure 1 as example) and the improvement in efficiency of QD solar cells through their co-sensitization with phthalocyanines.[6]

Acknowledgements. This work has been supported by the Spanish Ministerio de Economía y Competitividad, Generalitat Valenciana and the European FEDER funds (grants CTQ2011-26455, PROMETEO 2012/010 and ISIC/2012/008)
Figure 1. Chemical structure of a disulfide substituted bisphthalocyanine

Figure 1
Indium Porphyrin Frameworks: An Efficient Photocatalytic Platform for Organic Synthesis
Authors: Zhang Jian 
Published: February 2020

Porphyrinic metal-organic frameworks (PMOFs) are a class of hybrid materials consisting of metal-ion clusters bound by porphyin based organic ligands. Porphyrinic ligands are of particular interest due to their unique photo-, electro-, and catalytic properties. In addition, porphyrins offer a rare example of a four-fold axis of symmetry in organic ligands which is highly desirable for designing new MOF architectures. Conventional porphyrin ligands for MOF synthesis contain two or four terminal carboxy groups for metal binding. However, many of these structures require an additional “pillar” molecule in order to form 3D porous structures, which inherently increases the complexity of the crystallization process. To overcome this, one strategy in ligand design is to maintain the high symmetry and rigidity in the organic linker, yet increase the number of carboxy binding sites, which in effect renders the porphyrinic ligand “self-pillaring.” This presentation will focus on the structural characterization of these novel porphyrinic MOF architectures. In particular, the synthesis and photocatalytic properties of a novel In-based porphyrinic MOF will be discussed in detail. The mechanistic study of the catalytic activity will also be presented.
Nanoscale Assembly & Chemical Modification of Carbon Nanotubes & Graphene
Authors: Kim Sang Ouk 
Published: February 2020

Graphitic carbon nanomaterials, including fullerene, carbon nanotubes and graphene, attract enormous research attention for their outstanding material properties along with molecular scale dimension. The optimized utilization of those graphitic carbons in various application fields inevitably requires the subtle controllability of their structures and properties. In this regard, the substitutional doping of heteroelements, such as Boron or Nitrogen, into the graphitic plane offers robust and reliable solution. In this presentation, our recent research achievements associated to nanoscale molecular scale assembly of B- or N-doped graphitic carbon nanomaterials will be presented [1,2]. In our approach, graphitic carbons can be efficiently processed into various three-dimensional structures via self-assembly principles. For instance, vertical carbon nanotube forest can be grown from graphene film surface to constitute three-dimensional carbon hybrid materials [3]. Those carbon assembled structures with extremely large surface and high electro-conductivity are potentially useful for catalysis, energy storage and so on. Aqueous dispersion of graphene oxide shows liquid crystalline phase, whose spontaneous molecular ordering is useful for display or fiber spinning [4,5]. In addition, the substitutional doping of graphitic carbon with B- or N- was achieved via pre- or post-synthetic treatment. The resultant chemically modified graphitic carbons with tunable workfunction and remarkably enhanced surface activity could be employed for organic solar cells, organic light emitting diodes, nanocomposites for improved functionalities and device performances [6,7].
References

S. H. Lee, D. H. Lee, W. J. Lee and S. O. Kim, Adv. Funct. Mater. 21, 1338 (2011).

U. N. Maiti, W. J. Lee, J. M. Lee, Y. T. Oh, .J. Y. Kim, J. E. Kim, J. Shim, T. H. Han and S. O. Kim, Adv. Mater. 26, 40 (2014).

D. H. Lee, J. E. Kim, T. H. Han, J. W. Hwang, S. Jeon, S.-Y. Choi, S. H. Hong, W. J. Lee, R. S. Ruoff and S. O. Kim, Adv. Mater. 22, 1247 (2010).

J. E. Kim, T. H. Han, S. H. Lee, J. Y. Kim, C. W. Ahn, J. M. Yun and S. O. Kim, Angew. Chem. Int. Ed. 50, 3043 (2011).

J. Y. Kim and S. O. Kim, Nat. Mater. 13, 325 (2014).

L. Lu, T. Xu, W. Chen, J. M. Lee, Z. Lou, I. H. Jung, H. I. Park, S. O. Kim and L. Yu, Nano Lett. 13, 2365 (2013).

D. J. Li, U. N. Maiti, J. W. Lim, D. S. Choi, W. J. Lee, Y. T. Oh, G. Y. Lee and S. O. Kim, Nano Lett. 14, 1228 (2014).
Osmotic Pressure Effects Reveal a Specific Dehydration-Induced Hydrophobic Electron Transfer Structure Comprising Cytochrome C and Cytochrome C Oxidase
Authors: Ishimori Koichiro 
Published: February 2020

In the mitochondrial respiratory chain, Cytochrome c oxidase (CcO) accepts electrons from Cytochrome c (Cyt c) to reduce molecular oxygen. Previous studies showed that the complex formation of Cyt c with CcO is characterized by the positive entropy change, suggesting the dehydration from hydrophobic residues, but no experimental evidence of such dehydration has been reported. To confirm the dehydration during the complex formation between Cyt c and CcO, we focused on the partial molar volume change of protein (ΔV
W) for the complex formation, which reflects the volume of dehydrated water molecules. ΔV
W is correlated with the osmotic pressure (π) dependence of the K
d.
Osmotic pressure was increased by addition of sugars or polyols having no specific interactions with proteins and K
d was estimated by the Michaelis-Menten analysis of the steady state kinetics for the electron transfer from Cyt c to CcO.
As Figure 1 shows, the K
d value is decreased with increasing the osmotic pressure, corresponding to the negative ΔV
W of – 300 ± 78 mL mol-1. Assuming that the partial molar volume change of one hydrated water molecule around hydrophobic residues would be－17.5 mL mol-1, the volume change we obtained here corresponds to the dehydration of 17 ± 4 water molecules. Considering that the entropy change from the dehydration (dehydΔS) of one water molecule was estimated to be 5.5 JK-1mol-1, dehydΔS of 17 water molecules corresponds to ~90 JK-1mol-1, which is about 75% of total entropy change for the Cyt c-CcO complex formation. The dehydration is, therefore, one of the major factors to increase the entropy for the complex formation.
To identify the dehydration sites from hydrophobic residues in the interaction site for CcO on Cyt c, we mutated Ile11 or Ile81, hydrophobic amino acid residues in the interaction site for CcO [1], to Ala, an amino acid residue having a smaller side chain and less number of the hydrated water molecules. As clearly illustrated in Figure 1, the slope of the osmotic pressure dependence of K
d for the Ile mutant is less steep than that for the wild type protein. The estimated numbers of the dehydrated water molecules were reduced to 13 ± 3 and 8 ± 2 for the Ile11 and Ile81 mutants, respectively. The reduced numbers of the dehydrated water molecules in these Ile mutants indicate that the hydrated water molecules around Ile11 and Ile81 were expelled to the solvent in the complex formation between Cyt c and CcO.
In conclusion, we successfully identified that about 17 water molecules are dehydrated in the Cyt c-CcO complex formation and the primary dehydration sites are Ile11 and Ile81. Such dehydration from the hydrophobic residues can be a major factor to increase the entropy, facilitating the complex formation and the electron transfer from Cyt c to CcO.
References
[1] Sakamoto, K. et al., PNAS., 108, (2011), 12271

Figure 1
Porphyrins and Other Chromophores with Antioxidant Substituents
Authors: Hill Jonathan P. , Jin Shangbin , Labuta Jan , Ishihara Shinsuke , Ariga Katsuhiko 
Published: February 2020

Oxoporphyrinogens1,2 are a class of porphyrinoid generally containing a tetrapyrrole macrocycle with oxo or oxocyclohexadienylidene groups substituted at their periphery. They are unique in that their physical structures are coupled to their electronic structures depending on the electrochemical state of the molecule. Variations in electronic conjugation over the core tetrapyrrole and substituents affect electronic absorptive properties. Using these features we have developed oxoporphyrinogens as molecular switching elements and for sensing applications involving chemical species including water and chiral compounds.3,4 Tetrapyrroles with two or four conjugating substituents as well as corroles have been prepared and investigated for their properties depending on tautomerism,5 guest binding by hydrogen bonding and structural changes due to photoredox processes. The syntheses and mechanisms of action of the switching and sensing properties will be presented and discussed. Oxoporphyrinogens were developed from a porphyrin substituted with antioxidant 2,6-di-t-butylphenol groups. We have also investigated the synthesis and properties of other similarly substituted chromophores and will discuss some of the relevant properties.6,7

References
(1) F. D’Souza, N. K. Subbaiyan, Y. Xie, J. P. Hill, K. Ariga, K. Ohkubo, S. Fukuzumi, J. Am. Chem. Soc. (2009) 131, 16138–16146. (2) J. P. Hill, I. J. Hewitt, C. E. Anson, A. K. Powell, A. L. McCarthy, P. Karr, M. Zandler, F. D’Souza, J. Org. Chem. (2004) 69, 5861–5869. (3) S. Ishihara, J. Labuta, T. Šikorský, J. V. Burda, N. Okamoto, H. Abe, K. Ariga, J. P. Hill, Chem. Commun. (2012) 48, 3933–3935 (4) A. Shundo, J. Labuta, J. P. Hill, S. Ishihara, K. Ariga, J. Am. Chem. Soc. (2009) 131, 9494–9495; J. Labuta, S. Ishihara, A. Shundo, S. Arai, S. Takeoka, K. Ariga, J. P. Hill, Chem. Eur. J. (2011) 17, 3558–3561. (5) Y. Xie, J. P. Hill, A. L. Schumacher, P. A. Karr, F. D’Souza, C. E. Anson, A. K. Powell, K. Ariga, Chem. Eur. J. 2007, 13, 9824–9833. (6) J. P. Hill, N. K. Subbaiyan, F. D’Souza, Y. Xie,

S. Sahu, N. M. Sanchez-Ballester, K. Ariga, Chem. Commun. (2012) 48, 3951–3953. (7) A. Jana, H. Gobeze, M. Ishida, T. Mori, K. Ariga, J. P. Hill, F. D’Souza Dalton Trans. (2014) in press, DOI: 10.1039/C4DT03157A.