bluuebunny/crossref_metadata_2025_split huggingface dataset:
Porphyrinoids for Molecular Photovoltaics
Authors: Torres Tomas , Carrascosa Hector , Lavarda Giulia , Medina Diana Paola , Ince Mine , Trukhina Olga , Fernández-Ariza Javier , Garcia-Iglesias Miguel , Zango German , Urbani Maxence , Rodriguez-Morgade M. Salome , Martínez-Díaz M. Victoria 
Published: February 2020

In this contribution, hexachlorosubphthalocyanines SubPcCl6-X bearing different axial substituents (X) have been synthesized and used as novel electron acceptors in bulk-heterojunction organic solar cells. Solar cells with subphthalocyanines as the electron acceptors and PTB7-Th as the electron donor exhibit a power conversion efficiency up to 4% and an external quantum efficiency approaching 60% benefitting from significant photocurrent contribution from both electron donor and acceptor. These results indicate a promising prospect of developing non-fullerene acceptors based on subphthalocyanines and structurally related systems for highly efficient solution processed organic solar cells [1]. On the other hand, an unsymmetrical, push–pull porphyrazine derivative bearing an isoindole-4-carboxylic acid moiety (TT112) have been synthesized and incorporated in a dye-sensitized solar cell (DSSC). The device, which constitutes the first example of a porphyrazine-sensitized solar cell, exhibits a maximum power conversion efficiency of 3.4% [2].
Finally, easily accessible tetra-5-hexylthiophene-, tetra-5-hexyl-2,2’-bisthiophene-substituted zinc phthalocyanines (ZnPcs) have been employed as hole transporting materials (HTMs) in mixed-ion perovskite [HC(NH2)2]0.85(CH3NH3)0.15Pb(I0.85Br0.15)3
solar cells reaching the highest power conversion efficiency (PCE) reported so far for phthalocyanines. The resulting photovoltaic performance was strongly influenced by both, individual optoelectronic properties of ZnPcs and the aggregation of these tetrapyrrolic semiconductors in the HTM layer. The optimized devices exhibited a record PCE of 17.5% for tetra-5-hexylthiophene-based analogue under standard global AM 1.5 illumination. These results boost up the potential large-scale applications of solution-processed ZnPc derivatives as stable and economic hole-transport materials, opening new frontiers towards a realistic, efficient and inexpensive energy production [3].
[1] C. Duan, G. Zango, M. García Iglesias, F. J. M. Colberts, M. M. Wienk, M. V. Martínez-Díaz, R. A. J. Janssen, T. Torres, Angew. Chem. Int.. Ed. Engl.
2017, in press.
[2] J. Fernández-Ariza, M. Urbani, M. Grätzel, M. S. Rodríguez-Morgade, M. K. Nazeeruddin, T. Torres, ChemPhotoChem
2016, DOI: 10.1002/cptc.201600004
[3] K. T. Cho, O. Trukhina, C. Roldán-Carmona, M. Ince, P. Gratia, G. Grancini, P. Gao, T. Marszalek, W. Pisula, P. Y. Reddy, T. Torres, M. K. Nazeeruddin, Adv. Energ. Mat.
2016, in press
Highly Efficient ( >8%) Porphyrin-Based Bulk Heterojunction Organic Photovoltaics
Authors: Cuesta Virginia , Vartanian Maida , Arrechea Susana , de la Cruz Pilar , Singhal Rahul , Sharma Ganesh , Langa Fernando 
Published: February 2020

Solution-processed organic solar cells (OSC) are a topic of current scientific interest as a complementary photovoltaic technology to current silicon solar cells owing to their solution processability, potential low cost of fabrication, light weight and high transparency. Now, the power conversion efficiency (PCE) of solution-processed organic solar cells based on a single BHJ active layer using a low-band-gap small molecule has exceeded 10%, which is comparable to those of polymer counterparts.
Porphyrins, which are synthetic analogues of natural chlorophylls, are of special interest, because they are known to be a natural choice as light-harvesting antenna systems that are involved in energy and electron transfer processes. In recent years, there has been a great focus of interest on the field of solution-processed BHJ organic solar cells using porphyrin derivatives as donors, which resulted in PCEs up to 9.06 %. [1]
Here, we will present the synthesis, optical, electrochemical and photovoltaic properties of new porphyrin A-D-A and D-A-D derivatives used as donor, in BHJ solar cells, with PC71BM as acceptor reaching excellent efficiencies, higher than 8%.

References

[1] K. Gao, J. Miao, L. Xiao, W. Deng, Y. Kan, T. Liang, C. Wang, F. Huang, J. Peng, Y. Cao, F. Liu, T. P. Russell, H. Wu, X. Peng. Adv. Mater. 2016, 28, 4727.
[2] G. Morán, S. Arrechea, P.de la Cruz, V. Cuesta, S. Biswas, E. Palomares, G. D. Sharma and F. Langa, J. Mater. Chem. A,
2016, 4, 11009.
[3] S. Arrechea, A. Aljarilla, P. de la Cruz, E. Palomares G. D. Sharma, F. Langa. Nanoscale2016, 8 , 17953.
[4] V. Cuesta, M. Vartanian, P. de la Cruz, R. Singhal, G. D. Sharma and F. Langa, J. Mater. Chem. A,
2017 (in press) DOI: 10.1039/C6TA09408B.

Figure 1
A Bio-Inspired Approach Towards NIR Emissive Ytterbium(III) Complexes
Authors: Ning Yingying , Zhang Jun-Long 
Published: February 2020

Design of near infrared (NIR) emissive lanthanides such as ytterbium (Yb), erbium (Er) and neodymium (Nd) attracts considerable attentions for the potential applications in telecommunications, optical materials and biological imaging. Exploring an appropriate antenna ligand with the lowest triplet excited state (T1) to efficiently sensitize Ln emission plays a central role to overcome the forbidden f-f transition. To address this issue, natural light harvesting system sets a golden standard for harnessing sunlight power and energy transfer process with molecular precision. A prominent example is given by chlorophylls b, d, f widespread in land plants and cyanobacteria and algae of ocean, respectively, with gradually red shifted Q bands mainly differing from β-formyl substituent orientation. In contrast to modeling studies on deciphering how chlorophylls confer light harvesting function, much less has been reported regarding the application of such insights in designing luminescence materials.1-4 In this work, we reported the significant effect, arising from subtle structural changes, on tuning energy transfer process from the triplet state (T1) of ligand to Yb(III). Minor β-substituent orientation change in Yb cis/trans-porphodilactones (Yb-1 and Yb-2) significantly influences their NIR emissive properties that Yb-1 presented significant enhanced NIR luminescence and high thermo-sensitivity compared to Yb-2 (> 10 times). Combining with spectroscopy studies, we found strong back energy transfer process in Yb-1 but ineffective T1 → Ln* energy transfer in Yb-2. The strategy learning from nature should open a new method for designing NIR functional lanthanide complexes.
1. X.-S. Ke, Y. Chang, J.-Z. Chen, J. Tian, J. Mack, X. Cheng, Z. Shen* and J.-L. Zhang*, J. Am. Chem. Soc., 2014, 136, 9598-9607;
2. X.-S. Ke, H. Zhao, X. Zou, Y. Ning, X. Cheng, H. Su*, and J.-L. Zhang* ,J. Am. Chem. Soc., 2015, 137, 10745-10752;
3. X.-S. Ke, B.-Y. Yang, X. Cheng, S. L.-F. Chan, and J.-L. Zhang, Chem. Eur. J., 2014, 20, 4324-4333;
4. X. S. Ke, J. Tang, J. J. Chen, Z. Y. Zhou, J.-L. Zhang*, ChemPlusChem, 2015, 80, 25, 237-252;

Figure 1
Supramolecular Assemblies of a Water-Soluble Diprotonated Porphyrin and Heteropolyoxometalates
Authors: Kojima Takahiko 
Published: February 2020

Photocatalytic oxidation of organic substrates has been of great interest in terms of utilization of photon energy to produce useful materials from abundant feedstock. As a photocatalyst that can mediate electron transfer (ET) from an oxidation catalyst to an oxidant upon photoexcitation, porphyrins can be useful in light of the strong visible-light absorption and clear redox behavior. Although porphyrins have been used as photocatalysts for reduction of organic substrates, photocatalytic oxidation of organic substrates has been seldom reported by using porphyrins as photocatalysts.
So far, we have established the utility of diprotonated porphyrins as electron acceptors in photoinduced ET.1 On the basis of the concept, we prepared a water-soluble and saddle-distorted porphyrin, which can act as an electron acceptor in photoinduced ET upon diprotonation. The porphyrin (H2P4+) possesses four N-methylpyridinium-4-yl substituents at the para positions of the four meso-phenyl groups of dodecaphenylporphyrin. We observed proton-coupled electron transfer processes of the diprotonated form of H2P4+, H4P6+, in water to establish the Pourbaix diagram of H4P6+. We also determined the pKa value of the first protonation/deprotonation equilibrium to form the monoprotonated H3P5+ (pKa1 = 4.04) and that of the second one to afford H2P4+ (pKa2 = 7.83).
The highly positively charged H4P6+ was revealed to form supramolecular assemblies with negatively charged heteropolyoxometalates (POMs) in the ratio of H4P6+ : POM = 1 : 2 in water at pH 3 as indicated by Job's plots. Based on the redox properties of H4P4+ and the formation of supramolecular assemblies, we examined intra-supramolecular photoinduced ET from heteropolyoxometalates as electron donors to H4P6+ as an electron acceptor in water at pH 3 using femto-second laser flash photolysis upon photoexcitation at 393 nm. First-order rate constants of ET were analyzed on the basis of the Marcus theory of ET to determine the reorganization energy of ET to be 0.74 eV and the electronic coupling matrix element (V) to be 43 cm-1.
We also examined its application to photocatalytic oxidation of organic substrates in water, using H4P6+ as a photocatalyst, Na2S2O6 as an oxidant, and a Ru-substituted POM (RuPOM) as an oxidation catalyst, under the visible light irradiation. Preliminary results on the photocatalytic oxidation of benzyl alcohol were 560 turnovers for 4h; blank tests clearly suggest that H4P6+, RuPOM, the oxidant, and photoirradiation are all required to perform the photocatalytic reaction.
References
1. S. Fukuzumi, T. Honda, T. Kojima, Coord. Chem. Rev. 2012, 256, 2488-2508.
Supramolecular Chirogenesis in Bis- and Multi-Porphyrin Systems: Recent Developments and Further Perspectives
Authors: Borovkov Victor 
Published: February 2020

Supramolecular chirogenesis is a fundamentally novel interdisciplinary field of research being a smart combination of supramolecular/nano chemistry and chiral science. Supramolecular chirogenesis deals with the phenomenon of “symmetry breaking” in achiral multi- or unimolecular host systems by chiral guests (and vice versa), and is achieved by the rational application of specific non-covalent interactions via a chirality information transfer mechanism.
Recently, we have discovered a novel and very efficient supramolecular chirogenic system based upon an achiral ethane-bridged bis(metallo- or free base octaethylporphyrin).1-6 Upon interaction with the corresponding chiral guests, there are ligand induced structural deformations in the achiral host, resulting in a asymmetric orientation of the two porphyrin units and subsequent pronounced and easily detectable spectral changes monitored by various spectroscopies. Particularly, through-space exciton coupling between the porphyrin electronic transitions induces bisignate Cotton effects in the circular dichroism (CD) spectra. Significantly, the sign of the observed CD couplet is unequivocally correlated with the absolute configuration of the chiral ligand used, allowing us to develop an absolute configuration sensor for enantiopure amines, alcohols, acids. This system possesses a high degree of chiroptical activity, which allows the differentiation of one of the smallest homologous elements of organic chemistry, i.e. the methylene subunit, such as between methyl and ethyl groups attached to the asymmetric carbon; further, it is able to sense a remote chiral center at a position beta to the binding group. It was also found that this system is highly sensitive to various internal and external controlling factors such as the structure of guest molecules, stoichiometry, number of binding sites, solvent, temperature and phase transition.
Further developments and prospects toward new chirogenic systems on the basis of heterometallic bis- and multi-porphyrin structures will be discussed.

V. Borovkov, Symmetry
2014, 6, 256.

V. Borovkov, Symmetry
2010, 2, 184.

V. Borovkov, Y. Inoue, Eur. J. Org. Chem.
2009, 189.

G. A. Hembury, V. V. Borovkov, Y. Inoue, Chem. Rev.
2008, 108, 1

V. V. Borovkov, Y. Inoue, Top. Curr. Chem.
2006, 265, 89.

V. V. Borovkov, G. A. Hembury, Y. Inoue, Acc. Chem. Res. 2004, 37, 449.
First Investigation of Single-Walled Carbon Nanotubes Handedness Chirality Utilized By Scanning Tunneling Microscopy
Authors: Ibrahim Ahmed , Liu Gang , Komatsu Naoki , Inose Tomoko , Handayani Murni , Chen Zhijin , Ogawa Takuji 
Published: February 2020

(n,m) chirality of single-walled carbon nanotubes (SWNTs) has been extensively identified as well as investigated and/or characterized using many spectroscopic techniques [1]. On the other hand, the identification of the absolute handedness chirality of SWNTs still big challenge to be achieved even though there are some attempts [2]. Hereby, we have distinguished the absolute handedness chirality of SWNTs for the first time by using scanning tunneling microscopy (STM). This can be accomplished by using supramolecular structures of some porphyrin derivatives i.e. 5,15-bisdodecylporphyrin (C12P) on the chital SWNTs surface. Two types of chiral SWNTs have been used in this study, right-handed helix
P
(or plus) type and left-handed helix
M
(or Minus) type [3]. As an exclusive finding, two opposite chiral supramolecular structures of C12P molecules have been observed on the chiral SWNT surface; reflecting the considerable effectiveness of the handedness chirality of SWNT on the supramolecular structures of organic molecules on its surfaces. This pivotal results directly open the gates towards the determination of the absolute handedness chirality of SWNT, as well as a key point for further understanding and building new supramolecular architectures on curved surfaces which can be used for designing and fabricating more advanced porphyrin-SWNTs based devices.

References

[1] N. Nakashima & F. Toshimitsu. Sci. Rep.
2015, 5, 18066; N. Nakashima & F. Toshimitsu. Nat. Commun.
2014, 5, 1; F. Wang et al.
Nanoscale
2011, 3,4117; H. Liu et al.
Nature communi.
2011, 2, 309; W. Xiaojun et al.
Nature communi. 2016, 7, 12899.
[2] H. Liu et al. Nano Lett.
2014, 14, 6237; S. Ghosh et al. Nat. Nanotechnol.
2010, 5, 443.
[3] N. Komatsu et al. Chem. Lett.
2010, 39, 1022; N. Komatsu et al. J. Am. Chem. Soc.
2010, 132, 10876; N. Komatsu et al. J. Am. Chem. Soc.
2013, 135, 4805; N. Komatsu et al.
J. Am. Chem. Soc.
2007, 129, 15947.

Figure 1
Study of Transport Properties of Polyelectrolyte-Cellulose Acetate Membranes
Authors: Hakanpää Janina , Yliniemi Kirsi , Wilson Benjamin Paul , Singer Ferdinand , Höhn Sarah , Kontturi Eero , Virtanen Sannakaisa 
Published: February 2020

The rapid and uncontrollable corrosion of Mg and Mg based alloys is one of the main obstacles in the development of Mg based temporal implant materials1,2; the potentially harmful corrosion products leading to the increase of local pH and release of H2 gas to the surrounding tissues are especially problematic. Therefore, the control over the dissolution rate and release of corrosion products is of high importance if Mg based materials are to be used as temporary biomedical implants. Earlier, the authors have developed a weak polyelectrolyte-cellulose acetate membrane (poly(N,N-dimethylaminoethyl methacrylate)-cellulose acetate=PDMAEMA:CA membrane), which can simultaneously control the dissolution rate of Mg as well as protect the surrounding environment from the high pH increase and H2 gas3.
In the present study, scanning electrochemical microscope (SECM) was used to investigate the transport properties of these membranes in more details. The results show that the PDMAEMA content controls the permeability of the membrane but also, a surprising time-dependent behaviour was observed: the permeability of the PDMAEMA:CA membranes decreased as a function of time and ellipsometer results showed that this behaviour is not related to the swelling of the membrane. Instead, the time-dependent behaviour might be an indicator of the conformational change of PDMAEMA molecules – either due to the screening of charges or change in degree of ionisation - blocking the membrane pores and this results in a change in permeability as a function of time. A material with such a time-dependent behaviour is an extremely interesting candidate when designing smart and responsive coatings and membranes for temporal biomedical implants.
(1) F. Witte, N. Hort, C. Vogt, S. Cohen, K. U. Kainer, R. Willumeit, F. Feyerabend, Current Opinion in Solid State and Materials Science, 2008, 12, 63-72.
(2) S. Virtanen, Mater. Sci. Eng. B, 2011, 176, 1600-1608.
(3) K. Yliniemi, B. P. Wilson, F. Singer, S. Höhn, E. Kontturi S. Virtanen, ACS Applied Materials and Interfaces, 2014, 6, 22393-22399.
Effect of Crevice Geometry on Corrosion Behavior of Carbon Steel in 5wt% NaCl Solution
Authors: Tada Eiji , Maeda Hatsumi , Nishikata Atsushi 
Published: February 2020

Perforation corrosion of steel sheet lapped joints such as door hems is one severe corrosion type taking place on automobiles. This is because the lapped joints are exposed to a corrosive solution containing de-icing salt during driving and the solutions flowing into the crevice at the lapped joints, causing severe corrosion. Therefore, it is quite important to evaluate corrosion degradation of steel at the crevice of the lapped joints. In this study, effect of crevice geometry on corrosion behavior of carbon steel is investigated by immersion tests in 5wt% NaCl solution. In order to mimic steel sheet lapped joints, a block jig made of ABS resin having a cylindrical crevice former was prepared by a 3D printer. Crevice geometry on carbon steel such as a gap between a steel and a jig, and a diameter of the crevice former was changed by employing the jigs with different geometry. It was found from the results of the immersion tests that steel corrosion mainly took place below the crevice former and little corrosion was observed on the outer part of the steel apart from the crevice former. Furthermore, weight loss of the steel sheet during the immersion tests decreased with increasing the diameter of the crevice former. These results suggested that steel corrosion proceeds under the crevice former by the differential aeration inside and outside of the crevice, forming anode and cathode areas on the steel surface in the solution.
The Effect of Cations on Carbon Steel Corrosion in Chloride Media
Authors: Baranwal Prince Kumar , Das Sudip , Rajaraman Prasanna Venkatesh 
Published: February 2020

The corrosion of carbon steel in chloride media has been investigated extensively in literature [1, 2]. However, the role of cations in carbon steel corrosion behavior is not widely reported. In the present work, the effect of Na+, K+ and NH4
+cations on the corrosion of carbon steel in chloride media is investigated via. potentiodynamic polarization, electrochemical impedance spectroscopy (EIS), and field emission scanning electron microscopy (FESEM) measurements. All the electrochemical measurements were carried out using a three electrode system, and after open circuit potential reaches a stable value. The carbon steel was used as working electrode. The reference and counter electrode were Ag/AgCl (3M KCl) and platinum wire respectively. The concentration of chloride is 10 wt.% for all the solutions. The polarization curves were obtained by scanning the electrode potential from -250 mV to 500 mV w.r.t OCP at a scan rate of 1 mV/s. The impedance spectra were obtained by applying an AC perturbation signal of 10 mV in the frequency range 100 kHz to 10 mHz.
The polarization measurements (Fig. 1) reveals that the corrosion rate is higher in case of ammonium chloride (NH4Cl) solution following the order NH4
+> K+ > Na+. Further, the polarization measurements, in case of chloride solutions containing Na+ and K+ cation shows the formation of passive layer on the carbon steel surface (the regime of insignificant current increase with potential) followed by breakdown of the same (the regime of increase in current) indicating susceptibility to pitting corrosion. While the anodic polarization curve in the presence of NH4
+cation does not show any sign of passivation. This implies that the carbon steel is more prone to uniform corrosion. These results suggest the formation of passive layer on the carbon steel surface and the mechanistic reaction pathway of carbon steel dissolution in chloride media is strongly influenced by the cations present in the solution.
The EIS measurements performed at open circuit potential, shows two time constant for all the cations (Fig.2). However, for NaCl and KCl system, the two time constants are merged and appears to be a single capacitive loop. The impedance data is analysed by an appropriate electrical equivalent circuit (EEC) and the EEC parameters are retrieved. Impedance results also confirms that the corrosion rate is higher in NH4Cl solution while lower in NaCl solution. So the presence of cations affect both the corrosion rate and the corrosion mechanism.
Keywords: Carbon steel, cations, chloride media, polarization, EIS References

1. K. Toba, M. Ueyama, K. Kawano and J. Sakai, "Corrosion of carbon steel and alloys in concentrated ammonium chloride solutions," NACE Intl., 68, 1049 (2012)
2. O. Forsen, J. Aromaa and M. Tavi, "Corroison reistance of different materials in dilute ammonium chloride bearing environments," Corros. Sci., 35, 297 (1993)

Figure 1
A New Cathode Material for Potassium-Ion Batteries
Authors: Kim Haegyeom , Kim Jae Chul , Bo Shou-Hang , Shi Tan , Ceder Gerbrand 
Published: February 2020

Lithium-ion batteries have succeeded in powering small portable electric devices due to their high energy density. However, it is still debatable whether mineral resources can meet the increasing demand associated with the growth of Li-ion into large scale energy storage systems. As a result, potassium- and sodium-ion batteries are considered alternative energy storage options because of the natural abundance of K and Na resources. Potassium’s standard redox potential is lower than that of Na and is even below Lithium’s potential in non-aqueous electrolytes (i. e. propylene carbonate (PC) and ethylene carbonate/diethyl carbonate electrolyte (EC/DEC)).1-3It is therefore likely that K ion batteries can deliver a high cell voltage as compared to Na and Li systems.
Only few cathode compounds are reported to date for K ion batteries. In this early stage, it is important to design cathode materials that can maintain their crystal structures during de/intercalation of large K ions. We develop a new cathode material for K ion batteries and investigate K storage mechanism in this new cathode compound by in-situdiffraction characterization combined with electrochemical measurements. Lastly, we further demonstrate the practical feasibility of K ion batteries by constructing full cells. We consider that this work can suggest a guideline to open up new research opportunities in the development of K ion batteries.

References

1. Eftekhari, A., Jian, Z. & Ji, X. Potassium Secondary Batteries. ACS Appl. Mater. Sci., (2016).
2. Marcus, Y. Thermodynamic functions of transfer of single ions from water to non-aqueous and mixed solvents: Part 3 - Standard potentials of selected electrodes. Pure and Applied Chemistry 57, 1129, (1985).
3. Komaba, S., Hasegawa, T., Dahbi, M. & Kubota, K. Potassium intercalation into graphite to realize high-voltage/high-power potassium-ion batteries and potassium-ion capacitors. Electrochem. Commun. 60, 172-175, (2015).