Intestinal obstruction as a result of intra-abdominal hematoma: a complication of low molecular weight heparin in pediatric patients. / Obstrucción intestinal por hematoma intraabdominal: una complicación de la heparina de bajo peso molecular en el paciente pediátrico.

INTRODUCTION: Hematomas are a rare cause of intestinal obstruction. Subcutaneous heparin can bring about direct punctures on small bowel loops, potentially leading to traumatic hematoma and intestinal obstruction. CASE REPORTS: We present three cases of pediatric patients with clinical signs of intestinal obstruction treated with subcutaneous heparin. Two cases had increased acute-phase reactants and radiological signs of intestinal suffering, so surgical treatment was decided upon, with intramural hematoma emerging as an intraoperative finding. The third case was conservatively managed with anticoagulant discontinuation and gut rest, since the patient had an adequate general condition and no findings compatible with ischemia or necrosis were noted in the complementary tests. DISCUSSION: The administration of subcutaneous heparin may cause intestinal wall hematomas due to its anticoagulating effect and to the risk of inadvertent punctures on small bowel loops.

INTRODUCCION: Los hematomas son una causa poco frecuente de obstrucción intestinal. La heparina subcutánea tiene riesgo de producir la punción directa de un asa intestinal, provocando un hematoma traumático que genere una obstrucción intestinal. CASOS CLINICOS: Se describen tres casos de pacientes pediátricos con clínica de obstrucción intestinal en tratamiento con heparina subcutánea. Dos casos presentaron elevación de reactantes de fase aguda y signos radiológicos de sufrimiento intestinal por lo que se optó por tratamiento quirúrgico, con el hallazgo intraoperatorio de hematoma intramural. El tercer caso fue manejado de manera conservadora con supresión de la anticoagulación y reposo intestinal, dado el adecuado estado general y ausencia de hallazgos compatibles con isquemia o necrosis en las pruebas complementarias. COMENTARIOS: La administración de heparina subcutánea puede provocar la aparición de hematomas de pared intestinal, tanto por su efecto anticoagulante, como por el riesgo de punción inadvertida de un asa intestinal.

Obstrucción intestinal por hematoma intraabdominal: una complicación de la heparina de bajo peso molecular en el paciente pediátrico / Intestinal obstruction as a result of intra-abdominal hematoma: a complication of low molecular weight heparin in pediatric patients

Introducción: Los hematomas son una causa poco frecuente deobstrucción intestinal. La heparina subcutánea tiene riesgo de producirla punción directa de un asa intestinal, provocando un hematoma trau-mático que genere una obstrucción intestinal. Casos clínicos: Se describen tres casos de pacientes pediátricos conclínica de obstrucción intestinal en tratamiento con heparina subcutánea.Dos casos presentaron elevación de reactantes de fase aguda y signosradiológicos de sufrimiento intestinal por lo que se optó por tratamientoquirúrgico, con el hallazgo intraoperatorio de hematoma intramural. Eltercer caso fue manejado de manera conservadora con supresión de laanticoagulación y reposo intestinal, dado el adecuado estado generaly ausencia de hallazgos compatibles con isquemia o necrosis en laspruebas complementarias. Comentarios: La administración de heparina subcutánea puedeprovocar la aparición de hematomas de pared intestinal, tanto por suefecto anticoagulante, como por el riesgo de punción inadvertida deun asa intestinal.(AU)

Introduction: Hematomas are a rare cause of intestinal obstruc-tion. Subcutaneous heparin can bring about direct punctures on smallbowel loops, potentially leading to traumatic hematoma and intestinalobstruction. Case reports: We present three cases of pediatric patients withclinical signs of intestinal obstruction treated with subcutaneous heparin. Two cases had increased acute-phase reactants and radiological signsof intestinal suffering, so surgical treatment was decided upon, withintramural hematoma emerging as an intraoperative finding. The thirdcase was conservatively managed with anticoagulant discontinuationand gut rest, since the patient had an adequate general condition andno findings compatible with ischemia or necrosis were noted in thecomplementary tests. Discussion: The administration of subcutaneous heparin may causeintestinal wall hematomas due to its anticoagulating effect and to therisk of inadvertent punctures on small bowel loops.(AU)

Anthracene-Fused Oligo-BODIPYs: A New Class of π-Extended NIR-Absorbing Materials.

Large π-conjugated systems are key in the area of molecular materials. Herein, we prepare via AuI -catalyzed cyclization a series of fully π-conjugated anthracene-fused oligo-BODIPYs. Their structural and optoelectronic properties were studied by several techniques, ranging from X-ray, UV/Vis, and cyclic voltammetry to transient absorption spectroscopy. As a complement, their electronic structures were explored by means of Density Functional Theory (DFT) calculations. Depending on the size and shape of the π-conjugated skeleton, unique features-such as face-to-face supramolecular organization, NIR absorption and fluorescence as well as strong electron accepting character-were noted. All in all, the aforementioned features render them valuable for technological applications.

Recent advances in subphthalocyanines and related subporphyrinoids.

Half a century after the synthesis of the first subporphyrinoid, the study of tripyrrole and trisoindole porphyrin analogues constitutes a fervent and rapidly expanding research area. The outstanding structural, electronic and optical features of these cone-shaped aromatic macrocycles render them attractive candidates for a wide variety of applications, ranging from optoelectronics to biomedicine. To tune their properties and exploit their functionalities, the development of novel methodologies for the synthesis and post-functionalization of these contracted porphyrinoids, as well as a deep understanding of their supramolecular organization and their implementation into multicomponent systems of increasing complexity are of paramount importance. Herein, a review of the most recent advances in the fundamentals and applications of subporphyrinoids is presented, which comprehensively cover the last decade of discoveries. The final aim is to highlight the chemical versatility and intriguing physicochemical features of subporphyrinoids, while providing an updated overview of their most promising applications.

Subphthalocyanines as Efficient Photosensitizers with Nanomolar Photodynamic Activity against Cancer Cells.

Because cancer is the second leading cause of death globally, investigation of new photosensitizers for photodynamic therapy is highly desirable. In this work, different peripherally substituted subphthalocyanines (SubPcs) with either a benzocrown moiety (CE-) or a tyrosine methyl ester (Tyr-) as the axial ligand have been prepared. Target SubPcs showed high ΦΔ values, >0.50 in EtOH. Both CE- and Tyr- moieties increased substantially the hydrophilicity of the compounds (log P = 1.79-2.63, n-octanol/PBS). Uptake to cells, subcellular localization, and monitoring of the progression of cell death over time are described. Improved spectroscopic behavior of the CE- series in cell culture medium resulted in higher photodynamic activity versus that of the Tyr- series. In particular, the peripherally triethylsulfanyl SubPc-CE exhibited extraordinarily low EC50 values of 2.3 and 4.4 nM after light activation and high TC50 values of 14.49 and 5.25 µM (i.e., dark toxicity without activation) on SK-MEL-28 and HeLa cells, respectively, which rank it among the best photosensitizers ever.

Subphthalocyaninato Boron(III) Hydride: Synthesis, Structure and Reactivity.

Subphthalocyanine (SubPc) chemistry has been limited so far by their high sensitivity toward strong nucleophiles. In particular, the substitution of the axial chlorine atom by a nucleophilic group in the case of less-reactive SubPcs, such as those bearing electron-withdrawing peripheral substituents, presents some limitations and requires harsh conditions. By taking advantage of the electrophilic character of DIBAL-H, it has been possible to prepare for the first time SubPc-hydride derivatives that exhibit high reactivity as hydroboration reagents of aldehydes. This hydride transfer requires using a typical carbonyl activator (trimethylsilyl triflate) and only one equivalent of aldehyde, affording SubPcs with an axial benzyloxy group in good yield. This transformation has proven to be a useful alternative method for the axial functionalisation of dodecafluoroSubPc, a paradigmatic SubPc derivative, by using electrophiles for the first time. Considering the increasing interest in SubPcs as electron-acceptor semiconductors with remarkable absorption in the visible range to replace fullerene in organic photovoltaic (OPV) devices, it is of the utmost importance to develop new synthetic methodologies for their axial functionalisation.

Nuevo abordaje anestésico en la cirugía de glaucoma: anestesia subtenoniana ampular y su influencia en el resultado a medio plazo / New anesthetic approach in glaucoma surgery: "Underbleb" subtenonian anesthesia and its influence in medium term outcome

OBJETIVO: Presentar una nueva variante de anestesia subtenoniana, en el área quirúrgica de la futura ampolla de filtración y su influencia en el éxito quirúrgico a medio plazo. MATERIAL Y MÉTODOS: Estudio retrospectivo de 97 cirugías (esclerectomía profunda no perforante -EPNP- o Faco EPNP) realizadas en pacientes con glaucoma crónico simple, comparando aquellas realizadas bajo nuestra técnica de anestesia subtenoniana anterior modificada «subampular» (ASA) frente a otro grupo control bajo anestesia peribulbar (AP) (n = 58 vs. 38). Se contrastaron la PIO, número de fármacos antiglaucomatosos y porcentaje de éxito total y parcial a 1, 3, 6, 12, 18 y 24 meses tras la cirugía. RESULTADOS: Ambos grupos fueron comparables en términos de edad, sexo, tipo de cirugía, número de fármacos y PIO preoperatoria. La PIO en el grupo intervenido bajo ASA descendió de forma similar respecto al grupo control sin diferencias significativas salvo en los 24 meses, donde la PIO fue 2mm menor (14,83 ± 2,87 vs. 17,61 ± 4,27 [p = 0,009]). Esto sucedió tanto para EPNP como para la FACO-EPNP. El número de fármacos postoperatorios fue algo menor a los 3, 6, y 18 meses, pero no estadísticamente significativo. El éxito total a los 24 meses fue mayor en el grupo de ASA respecto al control AP (62,5% vs. 51,6) al igual que el éxito parcial (100% vs. 71%). CONCLUSIÓN: Nuestra nueva técnica anestésica ASA no influye negativamente en el control tensional a medio plazo de la cirugía no perforante, sino que incluso podría contribuir al éxito quirúrgico a más largo plazo

PURPOSE: To present a new anterior subtenonian anesthesia approach in the area of the future filtration bleb and its influence on medium term surgical success. MATERIAL AND METHODS: Retrospective study of 97 surgeries, deep sclerectomy (DE) or phaco-deep sclerectomy (PHACO-DS), were performed in patients with open angle glaucoma (OAG) comparing our modified "underbleb" subtenonian anesthesia (USA) (n = 58) versus a control group under peribulbar anesthesia (PA) (n = 38). Main outcomes were intraocular pressure (IOP), number of antiglaucomatous drugs and total and qualificated success, compared during 1, 3, 6, 12, 18 and 24 months follow up after glaucoma surgery. RESULTS: Both groups were comparable in terms of age, gender, surgical technique, number of antiglaucoma drugs and preoperative IOP. The IOP in the USA group decreased as in PA control group without statistical significant differences except at 24 months, where the IOP was 2mm lower (14.83 ± 2.87 vs. 17.61 ± 4.27 (P = .009). This happened for both, DS and PHACO-DS surgeries. The number of postoperative drugs was lower at 3, 6, and 18 months but without statistically significant diferences. Total success rate at 24 months was higher in the USA group respect AP control group (62.5% vs. 51.6) as well as partial success (100% vs. 71%). CONCLUSION: Our new USA anesthetic technique does not have a negative impact in DS medium-term surgical success, even it could contribute to a longer-term improvement

New anesthetic approach in glaucoma surgery: "Underbleb" subtenonian anesthesia and its influence in medium term outcome. / Nuevo abordaje anestésico en la cirugía de glaucoma: anestesia subtenoniana ampular y su influencia en el resultado a medio plazo.

PURPOSE: To present a new anterior subtenonian anesthesia approach in the area of the future filtration bleb and its influence on medium term surgical success. MATERIAL AND METHODS: Retrospective study of 97 surgeries, deep sclerectomy (DE) or phaco-deep sclerectomy (PHACO-DS), were performed in patients with open angle glaucoma (OAG) comparing our modified "underbleb" subtenonian anesthesia (USA) (n=58) versus a control group under peribulbar anesthesia (PA) (n=38). Main outcomes were intraocular pressure (IOP), number of antiglaucomatous drugs and total and qualificated success, compared during 1, 3, 6, 12, 18 and 24 months follow up after glaucoma surgery. RESULTS: Both groups were comparable in terms of age, gender, surgical technique, number of antiglaucoma drugs and preoperative IOP. The IOP in the USA group decreased as in PA control group without statistical significant differences except at 24 months, where the IOP was 2mm lower (14.83 ± 2.87 vs. 17.61 ± 4.27 (P=.009). This happened for both, DS and PHACO-DS surgeries. The number of postoperative drugs was lower at 3, 6, and 18 months but without statistically significant diferences. Total success rate at 24 months was higher in the USA group respect AP control group (62.5% vs. 51.6) as well as partial success (100% vs. 71%). CONCLUSION: Our new USA anesthetic technique does not have a negative impact in DS medium-term surgical success, even it could contribute to a longer-term improvement.

Photoactive preorganized subphthalocyanine-based molecular tweezers for selective complexation of fullerenes.

The development of new chromophoric receptors capable of binding curved carbon nanostructures is central to the quest for improved fullerene-based organic photovoltaics. We herein report the synthesis and characterization of a subphthalocyanine-based multicomponent ensemble consisting of two electron-rich SubPc-monomers rigidly attached to the convex surface of an electron-poor SubPc-dimer. Such a unique configuration, especially in terms of the two SubPc-monomers, together with the overall stiffness of the linker, endows the multicomponent system with a well-defined tweezer-like topology to efficiently embrace a fullerene in its inner cavity. The formation of a 1 : 1 complex was demonstrated in a variety of titration studies with either C60 or C70. In solution, the underlying association constants were of the order of 105 M-1. Detailed physicochemical experiments revealed a complex scenario of energy- and electron-transfer processes upon photoexcitation in the absence and presence of fullerenes. The close proximity of the fullerenes to the electron-rich SubPcs enables a charge shift from the initially formed reduced SubPc-dimer to either C60 to C70.

Annulative π-extension of BODIPYs made easy via gold(i)-catalyzed cycloisomerization.

Here we report gold(i)-catalyzed cycloisomerization as a new powerful synthetic tool for the preparation of π-extended BODIPY derivatives. The catalytic system PPhF 3AuCl/AgSbF6 enables the synthesis of [b]-[2,1]naphtho-fused-BODIPYs (2a-2c) under mild conditions, in excellent yields and short reaction times. The reaction is totally regioselective to the 6-endo-dig product and for the α-position of the BODIPY, which is both the kinetically and thermodynamically favored pathway, as supported by the free energy profile calculated by means of Density Functional Theory (DFT). Moreover, this methodology also allows the synthesis of two new families of [b]-aryl-fused-BODIPYs, namely, [3,4]phenanthro- (2e and 2f) and [1,2]naphtho-fused (2g) BODIPYs. Their molecular and electronic structures were established by NMR and UV-vis spectroscopies as well as single-crystal X-ray diffraction analysis. As can be noted from the X-ray structures, 2a, 2e and 2g present interesting structural differences at both the molecular and packing level. Interestingly, despite being isomers, the UV/vis spectra of 2a and 2g revealed significant differences in their electronic structures. The origin of this finding was studied by Time-Dependent DFT calculations. Calculated DFT Nuclear Independent Chemical Shift (NICS(0)) values also supported the different electronic structures of 2a and 2g.

One-Pot Synthesis of π-Extended Fluorenone-Fused Subphthalocyanines.

A family of inherently chiral nonplanar aromatic chromophores, comprising Subphthalocyanines bearing fluorenone-fused units (SubFcs), have been prepared by an innovative one-pot synthesis, which relies on the standard cross-cyclotrimerization of phthalonitriles followed by intramolecular Friedel-Crafts acylation. Their Q-band absorption experiences a ca. 20 nm red shift per fused fluorenone as a consequence of the enlarged conjugated π-system.

Analysis of Kidney Donation and Its Relationship With Graft Failure of the Recipient at 1 Year.

INTRODUCTION: Currently, the shortage of organs available for kidney transplantation and a change in donors' and recipients' profiles (elderly, with cardiovascular risk, donors after cardiac death), it is becoming necessary to assess grafts from expanded-criteria donors (ECD) in order to have methods that allow us to predict viability and graft survival. OBJECTIVE: The aim of this study was to analyze the different methods of renal donor assessment (estimated glomerular filtration rate [eGFR], preimplantation biopsy, and Kidney Donor Profile Index [KDPI] score) as predictors of graft survival and renal function of our recipient at 1 year. METHODS: We performed a descriptive and retrospective study of 183 deceased donor kidney transplantations performed at our center between 2011 and 2015. We calculated the KDPI scores, donor eGFR was estimated using the Chronic Kidney Disease Epidemiology Collaboration Formula equation, and biopsies were evaluated using Banff classification. RESULTS: ECDs comprised 59.60%, 93% of donors had an eGFR ≥ 60 mL/min/1.73 m2, and 41% presented with a KDPI score ≥ 90%. The most frequent range in the biopsy score was 0-3. The 1-year graft survival rate was 86.90%. Factors that negatively influenced graft survival were donor/recipient age, ECD, KDPI, and cold ischemia time (CIT). CONCLUSION: Prolonged CIT and KDPI ≥ 90% were donor variables that were related to graft failure at 1 year in our center.

Prognostic implications of markers of the metabolic phenotype in human cutaneous melanoma.

BACKGROUND: Reprogramming of energy metabolism to enhanced aerobic glycolysis has been defined as a hallmark of cancer. OBJECTIVES: To investigate the role of the mitochondrial proteins, ß-subunit of the H+ -ATP synthase (ß-F1-ATPase), and heat-shock protein 60 (HSP60), and the glycolytic markers, glyceraldehyde-3-phosphate dehydrogenase (GAPDH) and pyruvate kinase M2 (PKM2), as well as the bioenergetic cellular (BEC) index, in melanoma progression. MATERIALS AND METHODS: The expression of energy metabolism proteins was assessed on a set of different melanoma cells representing the natural biological history of the disease: primary cultures of melanocytes, radial (WM35) and vertical (WM278) growth phases, and poorly (C81-61-PA) and highly (C8161-HA) aggressive melanoma cells. Cohorts of 63 melanocytic naevi, 55 primary melanomas and 35 metastases were used; and 113 primary melanoma and 33 metastases were used for validation. RESULTS: The BEC index was significantly reduced in melanoma cells and correlated with their aggressive characteristics. Overexpression of HSP60, GAPDH and PKM2 was detected in melanoma human samples compared with naevi, showing a gradient of increased expression from radial growth phase to metastatic melanoma. The BEC index was also significantly reduced in melanoma samples and correlated with worse overall and disease-free survival; the multivariate Cox analysis showed that the BEC index (hazard ratio 0·64; 95% confidence interval 0·4-1·2) is an independent predictor for overall survival. CONCLUSIONS: A profound alteration in the mitochondrial and glycolytic proteins and in the BEC index occurs in the progression of melanoma, which correlates with worse outcome, supporting that the alteration of the metabolic phenotype is crucial in melanoma transformation.

Peripherally Cyanated Subphthalocyanines as Potential n-Type Organic Semiconductors.

A series of peripherally dicyano-, tricyano-, and tetracyano-substituted subphthalocyanines (SubPcs) have been prepared through microwave-assisted, palladium-mediated cyanation of iodinated precursors. The introduction of π-accepting cyano groups in the macrocycle clearly influences its electronic and redox properties, which are dependent on the number and relative position of these substituents. Additional functionalization of the periphery of SubPcs with electron-donating or -withdrawing groups allows for a further fine-tuning of their features, leading to intensely absorbing, strongly electron-accepting panchromatic dyes with low-lying LUMO energy levels. Flash-photolysis time-resolved microwave conductivity measurements on vapor-deposited films demonstrate that some of these novel SubPc derivatives display remarkable intrinsic charge-carrier mobilities that are comparable to or larger than those of other known well-performing acceptor SubPcs; thus confirming their potential as n-type organic semiconductors for application in the fabrication of photovoltaic devices.

Anti-HLA Antibodies After Precocious Transplantectomy by Vascular Thrombosis.

BACKGROUND: Our objective in this study was to determine the effects of early renal transplantectomy on patients and the production of anti-human leukocyte antigen (anti-HLA) antibodies. METHODS: Between January 2003 and May 2017, we analyzed a group of patients for the presence of specific HLA class I and/or II donor-specific antibodies (DSA), their panel-reactive antibodies (PRA), and the time period in which the antibodies were still detectable after transplantectomy. RESULTS: Anti-HLA antibodies were detected in 60.8% of patients, 60.8% and 52.2% of those patients had anti-class I and anti-class II antibodies, respectively. DSA were detected in 91.7% of the anti-HLA class I patients. Class II DSA were detected all of the patients with anti-HLA class II antibodies. The average (mean ± SD) PRA levels in our patients after transplantectomy was 60 ± 34% in class I and 63 ± 36% in class II. CONCLUSION: Anti-HLA antibodies can be detected well after transplantectomy. Even if the kidney allograft had been transplanted for only a short time, when the intensity of immunosuppression was the highest, many patients developed anti-HLA antibodies. The patients who continued with immunosuppression after transplantectomy did not develop anti-HLA antibodies.

The Role of the Axial Substituent in Subphthalocyanine Acceptors for Bulk-Heterojunction Solar Cells.

Four hexachlorosubphthalocyanines SubPcCl6 -X bearing different axial substituents (X) have been synthesized for use as novel electron acceptors in solution-processed bulk-heterojunction organic solar cells. Subphthalocyanines are aromatic chromophoric molecules with cone-shaped structure, good solution processability, intense optical absorption in the visible spectral region, appropriate electron mobilities, and tunable energy levels. Solar cells with subphthalocyanines as the electron acceptor and PTB7-Th as the electron donor exhibit a power conversion efficiency up to 4 % and an external quantum efficiency approaching 60 % due to significant contributions from both the electron donor and the electron acceptor to the photocurrent, indicating a promising prospect of non-fullerene acceptors based on subphthalocyanines and structurally related systems.

Role of the Bulky Aryloxy Group at the Non-Peripheral Position of Phthalocyanines for Dye Sensitized Solar Cells.

To date ß-aryloxy-substituted designs have led to the best results in phthalocyanine-sensitized solar cells (Pc-SCs) because of their low aggregation properties. By incorporating the bulky semiflexible 2,6-diphenylphenoxy group at three α-positions of the Pc, different regioisomers were separated by column chromatography and their photovoltaic performance was thoroughly studied. Efficiencies in the range of 1.9-4.1 % were found, thus demonstrating the importance of the steric interaction between the substituents and the semiconductor surface, also in the case of bulky semiflexible substituents. It was discovered that regioisomers which presented greater steric hindrance around the anchoring group, had lower adsorption densities, and, consequently, lower short-circuit photocurrents (Jsc ) and efficiencies.

The Influence of Substituent Orientation on the Photovoltaic Performance of Phthalocyanine-Sensitized Solar Cells.

Phthalocyanines (Pcs) are used as sensitizers in dye-sensitized solar cells (DSSCs) because of their stability and intense absorption in the red and near-IR regions. Impressive progress has been made in photovoltaic efficiencies by introduction of bulky peripheral substituents to help suppress macrocycle aggregation. To reach benchmark efficiencies reported for other related dyes, new designs need to be explored. Single carboxy-ZnPc regioisomers substituted at the non-peripheral positions by rigid aryl groups have now been studied, which has shed light on the influence of steric hindrance and/or orientation of the substituent around the anchoring group on the photovoltaic response. The regioisomer bearing the aryl group far away from the anchoring group produces a more effective sensitization of the TiO2 films and higher short-circuit photocurrent density (Jsc). Taking advantage of the good photovoltaic performance in the near-IR region of this ZnPc, it was combined with another appropriate dye for panchromatic sensitization of the mesoporous photoelectrode and an increase of the overall device efficiency.

Photoinduced Electron Transfer in a Zinc Phthalocyanine-Fullerene Conjugate Connected by a Long Flexible Spacer.

A hexadodecyl-substituted zinc phthalocyanine covalently linked through a flexible spacer to a fullerene-ZnPc-C60 -has been investigated regarding electron transfer from the photoexcited, electron-donating ZnPc to the electron-accepting C60 . While ground-state interactions between electron donor and acceptor within ZnPc-C60 could not be detected via steady-state absorption spectroscopy, clear proof for excited-state interactions came from steady-state fluorescence spectroscopy. To this end, the fluorescence in ZnPc-C60 is strongly quenched with quantum yields in THF as low as 0.05. Insight into excited-state electron-transfer deactivation within ZnPc-C60 came from time-resolved femtosecond transient absorption spectroscopy. For example, upon exclusive excitation of the phthalocyanine within the ZnPc-C60 conjugate, a set of transients evolve featuring, on the one hand, the signature of the one-electron oxidized ZnPc radical cation and, on the other hand, of the one-electron reduced C60 radical anion. The analysis of the corresponding dynamics in chlorobenzene resulted in lifetimes for charge-separation and charge-recombination of 7.4 ps and 2.2 ns, respectively.

Energy Level Tuning of Non-Fullerene Acceptors in Organic Solar Cells.

The use of non-fullerene acceptors in organic photovoltaic (OPV) devices could lead to enhanced efficiencies due to increased open-circuit voltage (VOC) and improved absorption of solar light. Here we systematically investigate planar heterojunction devices comprising peripherally substituted subphthalocyanines as acceptors and correlate the device performance with the heterojunction energetics. As a result of a balance between VOC and the photocurrent, tuning of the interface energy gap is necessary to optimize the power conversion efficiency in these devices. In addition, we explore the role of the charge transport layers in the device architecture. It is found that non-fullerene acceptors require adjusted buffer layers with aligned electron transport levels to enable efficient charge extraction, while the insertion of an exciton-blocking layer at the anode interface further boosts photocurrent generation. These adjustments result in a planar-heterojunction OPV device with an efficiency of 6.9% and a VOC above 1 V.