Interface Engineering of Inverted Perovskite Solar Cells Using a Self‐doped Perylene Diimide Ionene Terpolymer as a Thickness‐Independent Cathode Interlayer

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Interface Engineering of Inverted Perovskite Solar Cells Using a Self-doped Perylene Diimide Ionene Terpolymer as a Thickness-Independent Cathode Interlayer†

In this study, we successfully synthesized a highly soluble, self-doping perylene imide-based ionene polymer (PNPDIN). By using it as a CIL material in inverted Perovskite Solar Cells (PerSCs), the power conversion efficiency (PCE) remarkably increased from 10.05% (without a CIL) to 16.97% (with PNPDIN). Moreover, a synergistic effect was achieved by combining PNPDIN with Bphen as a mixed CIL, leading to an outstanding PCE of 21.28% due to the favorable morphology and energy level alignment. Furthermore, the device's performance displayed excellent tolerance towards varying thicknesses of the mixed CIL, which was attributed to PNPDIN's high conductivity. Even at a film thickness of up to 37 nm, the optimized PCE remained at a high level of 20.46%. This superior mixed CIL materials may open promising avenues for efficient roll-to-roll processing of inverted PerSCs.


Comprehensive Summary

Inverted perovskite solar cells (PerSCs) are a highly promising candidate in the photovoltaic field due to their low-temperature fabrication process, negligible hysteresis, and easy integration with Si-based solar cells. A cathode interlayer (CIL) is necessary in the development of inverted devices to reduce the trap density and energy barrier between the electron transport layer (ETL) and the electrode. However, most CILs are highly thickness-sensitive due to low conductivity and poor film-forming. In this study, we report on a self-doping perylene imide-based ionene polymer (PNPDIN) used as CIL material to modify electrode in inverted PerSCs. PNPDIN exhibits high conductivity and a good solubility in polar solvent, which results in an improved power conversion efficiency (PCE) from 10.05% (device without a CIL) to 16.97%. When the blend of PNPDIN and Bphen was used as a mixed CIL, the PCE of PerSCs can be further increased to 21.28% owing to the excellent morphology and matched energy level. More importantly, the PCE of the device is highly tolerant to the thickness of the mixed CIL, which benefited from the high conductivity of PNPDIN. This development is expected to provide an excellent mixed CIL material for roll-to-roll processing efficient and stable inverted PerSCs.

Quotient of quotient graph a novel approach to compute π$$ \pi $$‐conjugated dendrimer and predict its properties

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Quotient of quotient graph a novel approach to compute π$$ \pi $$-conjugated dendrimer and predict its properties

Truxene, a polycyclic compound characterized by its unique C3$$ {C}_3 $$ topology and rigid planar structure, has interesting applications in the electronic and optoelectronic field. π$$ \pi $$-conjugated dendrimers have several potential applications in electronic and optoelectronic devices such as organic field-effect transistors, solar cells, and electroluminescent devices. Star-shaped molecules possess well-defined molecular structures as well as superior chemical purity and exhibit properties of strong blue emission. Different distance-based topological indices are computed for gradient star persistent π$$ \pi $$-conjugated dendrimer. This work helps to determine various properties of the dendrimers with truxenes which have application in disparate fields. Also, the graphical presentation may help in the comparative study of various properties and characteristics of the structure. Through linear regression, the photovoltaic, and electrochemical properties are compared with the π$$ \pi $$-conjugated dendrimer parameters and received excellent correlation.


Abstract

The role of dendrimers is getting updated and grabbing immense attention in many fields. Dendrimers are used in a broad spectrum, in specific, it is widely utilized in drug delivery, for targeted carrier and specific action. Also, in drug catalysis, it improves the solubility of poorly soluble drugs and increases the stability of active ingredients within the cores. Many researchers are interested in developing new dendrimers by using various compounds. π$$ \pi $$-conjugated dendrimers via truxenes and thienylethynylene units, are considered a promising material in the field of medicinal chemistry, bio-organic, and environmental sciences. In QSAR/QSPR, the structural analysis of chemical compounds is examined by topological descriptors. In this article, the various distance-based topological indices such as Wiener, Szeged, and Mostar of gradient star-persistent π$$ \pi $$-conjugated dendrimers are determined. Since gradient star-persistent π$$ \pi $$-conjugated dendrimers have odd cycles, the usual cut method is not applicable, therefore we use a new concept, the quotient of quotient graph to determine the numerical expression of various indices. An analysis of linear regression reveals that degree-based topological descriptors predict better physicochemical properties.

An overview of extracellular matrix and its remodeling in the development of cancer and metastasis with a glance at therapeutic approaches

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Abstract

The extracellular matrix (ECM) is an inevitable part of tissues able to provide structural support for cells depending on the purpose of tissues and organs. The dynamic characteristics of ECM let this system fluently interact with the extrinsic triggers and get stiffed, remodeled, and/or degraded ending in maintaining tissue homeostasis. ECM could serve as the platform for cancer progression. The dysregulation of biochemical and biomechanical ECM features might take participate in some pathological conditions such as aging, tissue destruction, fibrosis, and particularly cancer. Tumors can reprogram how ECM remodels by producing factors able to induce protein synthesis, matrix proteinase expression, degradation of the basement membrane, growth signals and proliferation, angiogenesis, and metastasis. Therefore, targeting the ECM components, their secretion, and their interactions with other cells or tumors could be a promising strategy in cancer therapies. The present study initially introduces the physiological functions of ECM and then discusses how tumor-dependent dysregulation of ECM could facilitate cancer progression and ends with reviewing the novel therapeutic strategies regarding ECM.

Electrically stimulated in vitro heart cell mimic of acute exercise reveals novel immediate cellular responses to exercise: Reduced contractility and metabolism, but maintained calcium cycling and increased myofilament calcium sensitivity

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Abstract

Cardiac cellular responses to acute exercise remain undescribed. We present a model for mimicking acute aerobic endurance exercise to freshly isolated cardiomyocytes by evoking exercise-like contractions over prolonged periods of time with trains of electrical twitch stimulations. We then investigated immediate contractile, Ca2+, and metabolic responses to acute exercise in perfused freshly isolated left ventricular rat cardiomyocytes, after a matrix-design optimized protocol and induced a mimic for acute aerobic endurance exercise by trains of prolonged field twitch stimulations. Acute exercise decreased cardiomyocyte fractional shortening 50%–80% (p < .01). This was not explained by changes to intracellular Ca2+ handling (p > .05); rather, we observed a weak insignificant Ca2+ transient increase (p = .11), while myofilament Ca2+ sensitivity increased 20%–70% (p < .05). Acidic pH 6.8 decreased fractional shortening 20%–70% (p < .05) because of 20%–30% decreased Ca2+ transients (p < .05), but no difference occurred between control and acute exercise (p > .05). Addition of 1 or 10 mM La− increased fractional shortening in control (1 mM La−: no difference, p > .05; 10 mM La−: 20%–30%, p < .05) and acute exercise (1 mM La−: 40%–90%, p < .01; 10 mM La−: 50%–100%, p < .01) and rendered acute exercise indifferent from control (p > .05). Intrinsic autofluorescence showed a resting NADstate of 0.59 ± 0.04 and FADstate of 0.17 ± 0.03, while acute exercise decreased NADH/FAD ratio 8% (p < .01), indicating intracellular oxidation. In conclusion, we show a novel approach for studying immediate acute cardiomyocyte responses to aerobic endurance exercise. We find that acute exercise in cardiomyocytes decreases contraction, but Ca2+ handling and myofilament Ca2+ sensitivity compensate for this, while acidosis and reduced energy substrate and mitochondrial ATP generation explain this.

In situ Injectable Tetra‐PEG Hydrogel Bioadhesive for Sutureless Repair of Gastrointestinal Perforation

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In situ Injectable Tetra-PEG Hydrogel Bioadhesive for Sutureless Repair of Gastrointestinal Perforation†

An in situ injectable Tetra-PEG hydrogel bioadhesive based on tetra-armed poly(ethylene glycol) amine (Tetra-PEG-NH2) and tetra-armed poly(ethylene glycol) succinimidyl succinate (Tetra-PEG-SS) with rapid gelation speed, excellent biocompatibility, and suitable degradability is developed for the sutureless repair of gastrointestinal perforations. The Tetra-PEG hydrogel can provide fluid-tight sealing and effective repair of gastrointestinal defects with neglectable postoperative adhesion, suppressed long-term inflammation, and enhanced angiogenesis.


Comprehensive Summary

Hydrogel bioadhesives represent promising and efficient alternatives to sutures or staples for gastrointestinal (GI) perforation management. However, several concerns remain for the existing bioadhesives including slow and/or weak adhesive, poor mechanical strength, low biocompatibility, and poor biodegradability, which largely limit their clinical application in GI perforation repair. In this work, we introduce an in situ injectable Tetra-PEG hydrogel bioadhesive (SS) composed of tetra-armed poly(ethylene glycol) amine (Tetra-PEG-NH2) and tetra-armed poly(ethylene glycol) succinimidyl succinate (Tetra-PEG-SS) for the sutureless repair of GI defects. The SS hydrogel exhibits rapid gelation behavior and high burst pressure and is capable of providing instant robust adhesion and fluid-tight sealing in the ex vivo porcine intestinal and gastric models. Importantly, the succinyl ester linkers in the SS hydrogel endow the bioadhesive with suitable in vivo degradability to match the new GI tissue formation. The in vivo evaluation in the rat GI injured model further demonstrates the successful sutureless sealing and repair of the intestine and stomach by the SS hydrogel with the advantages of neglectable postsurgical adhesion, suppressed inflammation, and enhanced angiogenesis. Together, our results support potential clinical applications of the SS bioadhesive for the high-efficient repair of GI perforation.

Increased Oxygen Evolution Activity in pH‐Universal Electrocatalyst: Urea‐Modified NiFeCoCN Medium‐Entropy Alloy

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Increased Oxygen Evolution Activity in pH-Universal Electrocatalyst: Urea-Modified NiFeCoCN Medium-Entropy Alloy†

C/N leads to the weakened adsorption ability of the oxygen-containing intermediates, facilitating the reduction of energy barrier, thus, NiFeCoCN MEA has excellent OER activity in pH-universal electrocatalyst.


Comprehensive Summary

The kinetic process of a slow oxygen evolution reaction (OER) always constrains the efficiency of overall water electrolysis for H2 production. In particular, nonprecious metal electrodes for the OER have difficulty in possessing excellent electrocatalytic activity and stability in pH-universal media simultaneously. In this work, urea is first used as a pore-forming agent and active C/N source to fabricate a nanoporous NiFeCoCN medium-entropy alloy (MEA) by high-temperature sintering based on the nanoscale Kirkendall effect. The NiFeCoCN MEA achieves an overpotential of 432 mV at a current density of 10 mA·cm–2 and a lower Tafel slope of 52.4 mV·dec–1 compared to the IrO2/Ti electrode (58.6 mV·dec–1) in a 0.5 mol/L H2SO4 solution. In a 1 mol/L KOH solution, the NiFeCoCN MEA obtains an overpotential of 175 mV for 10 mA·cm–2 and a Tafel slope of 40.8 mV·dec–1, which is better than IrO2/Ni foam. This work proves a novel strategy to design and prepare nanoporous MEA materials with desirable C/N species, which provides promising prospects for the industrial production of H2 energy.

Recent Progress of Fuel‐Driven Temporary Materials

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Recent Progress of Fuel-Driven Temporary Materials


Comprehensive Summary

Fuel-driven dissipative self-assembly, which is a well-established concept in recent years, refers to out-of-equilibrium molecular self-assembly initiated and supported by the addition of active molecules (chemical fuel). It widely exists in nature since many temporary, active micro- or nanostructures in living bodies are generated by the dissipative self-assembly of biomolecules. Therefore, the study on dissipative self-assembly provides a good opportunity to have an insight into the microscopic mechanism of living organisms. In the meantime, dissipative assembly is thought to be a potential pathway to achieve dynamic, temporary supramolecular materials. Recently, a number of temporary materials have been developed with the aid of strategies for realizing dissipative self-assembly. Some of their properties, including solubility, stiffness, turbidity, color, or self-healing ability, change upon the addition of chemical fuel but spontaneously restore with chemical fuel consumption. The dynamic of these materials brings them various unprecedented functions. In this review, the principles of fabricating a fuel-driven temporary material are first reviewed. Subsequently, recent examples of fuel-driven temporary materials are emphatically summarized, including gels, self-erased inks, nanoreactors, self-healing materials, nanochannels, and droplets. Finally, the challenges of developing fuel-driven temporary materials and some perspectives on the function and application of such kind of materials are discussed.

Recent advances in nickel catalyzed carbonylative reactions via the insertion of Carbon Monoxide

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Comprehensive Summary

Carbonyl compounds have attracted considerable attention due to their extensive applications in drug discovery. Furthermore, they are important synthetic intermediates for the construction of carbon-carbon and carbon-heteroatom bonds. Transition-metal-catalyzed carbonylation via the insertion of CO is one of the most efficient and straightforward strategies to access carbonyl compounds. However, most of the transition-metal-catalyzed carbonylative reactions require expensive and toxic noble-metal catalysts. Therefore, there is a growing demand for the exploration of nickel-catalyzed carbonylative reactions via the insertion of CO due to the earth abundance and low cost of nickel. Compared with the well-established palladium-catalyzed carbonylative reactions, nickel-catalyzed analogous transformations have been relatively underdeveloped. This is primarily because CO strongly binds to nickel, often resulting in catalyst poisoning. In recent years, some research groups have focused on using CO surrogates or NN2 pincer nickel catalyst to circumvent the formation of Ni(CO)4. Nickel-catalyzed carbonylation has been applied in the construction of carbonyl-containing compounds, such as ketones, carboxylic acids, thioesters, acyl chloride and carboxamides.

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Do Naturally Modified Nucleotides Contribute to Stabilizing Complexes between Ribosomes and Small Molecules? A Case Study with the Antitumor Drug Homoharringtonine

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Do Naturally Modified Nucleotides Contribute to Stabilizing Complexes between Ribosomes and Small Molecules? A Case Study with the Antitumor Drug Homoharringtonine

The large and highly branched antitumor homoharringtonine, here in black sticks, owing to its conformationally mobile nature can interact with a variety of nucleotides at site A of the ribosome PCT, like in a spider web.


Abstract

Modified nucleotides are ubiquitous with RNAs, also in contact with drugs that target the ribosome. Whether this represents a stabilization of the drug-ribosome complex, thus affecting the drug's affinity and possibly also intrinsic efficacy, remains an open question, however. The challenge of answering this question has been taken here with the only human-ribosome-targeting small-molecule currently in clinical use, the antitumor plant alkaloid homoharringtonine (HHT). The approach consisted in dissecting HHT-nucleotide interaction energies from QM-MM simulations in explicit water. What emerged is a network of mostly weak interactions of the large, branched HHT with standard nucleotides and a single modified nucleotide, out of the four ones present at PCT's A site. This is unlike the case of the small, compact marine antitumor alkaloid agelastatin A, which displays only a few, albeit strong, interactions with site-A ribosome nucleotides. This should aid tailoring drugs targeting the ribosome.

Photoinduced One‐Electron Oxidation of Estrone Derivatives: A Combined Steady‐State and Time‐Resolved Spectroscopy Investigation

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Photoinduced One-Electron Oxidation of Estrone Derivatives: A Combined Steady-State and Time-Resolved Spectroscopy Investigation

Photoinduced one-electron oxidation of a set of estrone derivatives (R-OX) with ammonium persulphate was carried out by means of steady-state and time-resolved spectroscopies. The photogenerated SO4⋅− oxidizes efficiently the estrones to the radical cations and a mesolytic fragmentation gave the phenoxyl radical with k frag of 104–105 s−1 that depend on the X−O bond dissociation energies.


Abstract

A detailed investigation of the photophysics and of the redox properties of a set of selected estrone carboxylate and sulfonate esters was carried out by means of steady-state and time-resolved spectroscopies. The observed dual fluorescence was assigned to an efficient intramolecular energy transfer from the aromatic moiety to the carbonyl group. On the other hand, the photoinduced monoelectronic oxidation of R−OX in the presence of persulphate anion is followed by mesolytic fragmentation of the so generated radical cation into the corresponding phenoxyl radical with rate constant values (k frag) of 104–105 s−1, that depend on the X−O bond dissociation energy values.