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Carbon dots (CDs), as a kind of zero‐dimensional nanomaterials, have been widely synthesized by bottom‐up methods from various precursors. However, the formation mechanism is still unclear and controversial, which also brings difficulty to the regulation of structures and properties. Only some tentative formation processes were postulated by analyzing the products obtained at different reaction times and temperatures. Here, the effect of crosslinking on the formation of carbonized polymer dots (CPDs) is explored. Crosslinking‐induced nucleation and carbonization (CINC) is proposed as the driving force for the formation of CPDs. Under hydrothermal synthesis, the precursors are initiated to polymerize and crosslink. The crosslinking brings higher hydrophobicity to generate the hydrophilic/hydrophobic microphase separation, which promotes dehydration and carbonization resulting in the formation of CPDs. Based on the principle of CINC, the influence factors of size are also revealed. Moreover, the dissipative particle dynamics (DPD) simulation is employed to support this formation mechanism. This concept of CINC will bring light to the formation process of CPDs, as well as facilitate the regulation of CPDs' size and photoluminescence. [ABSTRACT FROM AUTHOR]

The Suzuki–Miyaura cross‐coupling is one of the most important and powerful methods for constructing C−C bonds. However, the protodeboronation of arylboronic acids hinder the development of Suzuki–Miyaura coupling in the precise synthesis of conjugated polymers (CPs). Here, an anhydrous room temperature Suzuki–Miyaura cross‐coupling reaction between (hetero)aryl boronic esters and aryl sulfides was explored, of which universality was exemplified by thirty small molecules and twelve CPs. Meanwhile, the mechanistic studies involving with capturing four coordinated borate intermediate revealed the direct transmetalation of boronic esters in the absence of H2O suppressing the protodeboronation. Additionally, the room temperature reaction significantly reduced the homocoupling defects and enhanced the optoelectronic properties of the CPs. In all, this work provides a green protocol to synthesize alternating CPs. [ABSTRACT FROM AUTHOR]

Photonic synapses with the dual function of optical signal detection and information processing can simulate human visual system. However, photonic synapses with selective detection of short‐wavelength infrared (SWIR) light have never been reported, which can not only broaden the human vision region but also integrate neuromorphic computation and infrared optical communication. Here, organic photonic synapses based on a new donor‐acceptor copolymer P1 are fabricated, which exhibit excellent synaptic characteristics with selective detection for SWIR and extremely low energy consumption (2.85 fJ). The working mechanism is rooted in energy level barriers and unbalanced charge transportation. Moreover, these photonic synapses demonstrate excellent performance in multi‐signal logic editing, letter imaging and memory with noise reduction function. This contribution provides ideas of constructing selective‐response synapses for artificial visual system and neuromorphic computing. [ABSTRACT FROM AUTHOR]

Transition metal (TM)‐based bimetallic spinel oxides can efficiently activate peroxymonosulfate (PMS) presumably attributed to enhanced electron transfer between TMs, but the existing model cannot fully explain the efficient TM redox cycling. Here, we discover a critical role of TM−O covalency in governing the intrinsic catalytic activity of Co3−xMnxO4 spinel oxides. Experimental and theoretical analysis reveals that the Co sites significantly raises the Mn valence and enlarges Mn−O covalency in octahedral configuration, thereby lowering the charge transfer energy to favor MnOh–PMS interaction. With appropriate MnIV/MnIII ratio to balance PMS adsorption and MnIV reduction, the Co1.1Mn1.9O4 exhibits remarkable catalytic activities for PMS activation and pollutant degradation, outperforming all the reported TM spinel oxides. The improved understandings on the origins of spinel oxides activity for PMS activation may inspire the development of more active and robust metal oxide catalysts. [ABSTRACT FROM AUTHOR]

Benzidin und seine Derivate können im menschlichen Körper zu krebserregenden Aminen umgewandelt werden. Aus diesem Grund wird den potentiellen Risiken (z. B. Blasenkrebs) bei Kontakt mit kommerziell erhältlichen Benzidin ‐ haltigen und analogen Farbstoffen wachsende Aufmerksamkeit geschenkt.1, 2 Einige Phenolderivate, die in der Herstellung alltäglicher Produkte eingesetzt werden, haben Ähnlichkeiten mit hormonaktiven Stoffen und erhöhen möglicherweise das Brustkrebsrisiko.3, 4 In der hier vorgestellten Arbeit haben wir zum ersten Mal multifunktionale Nanokomposite konstruiert, die den hochempfindlichen Nachweis, die Manipulation und lichtinduzierte Zersetzung toxischer Benzidin ‐ und Phenolderivate ermöglichen. Magnetische TiO2 ‐ Nanokomposite (M ‐ TiO2 ‐ NCs) wurden synthetisiert und mit p ‐ Aminothiophenol (PATP) zur Bindung der Zielmoleküle über eine Azo ‐ Kupplung funktionalisiert. Anhand der spezifischen spektroskopischen Signaturen in den oberflächenverstärkten Resonanz ‐ Raman ‐ Spektren (SERRS; surface ‐ enhanced resonance Raman scattering) der Azoprodukte war es möglich, zielgerichtet toxische Aniline und Phenole zu identifizieren und schließlich deren Azoprodukte an der TiO2 ‐ Oberfläche photokatalytisch abzubauen, ein Prozess, der zudem durch Ausnutzung der Plasmonenresonanz eingebetteter Ag ‐ Partikel verstärkt werden konnte. Doppelfunktion: Magnetische TiO2 ‐ Nanokomposite (M ‐ TiO2 ‐ NCs) wurden zur Bestimmung und Beseitigung von toxischen Anilinen und Phenolen funktionalisiert. Die Analytmoleküle werden über eine Azokupplung an die M ‐ TiO2 ‐ NCs gebunden und mittels TiO2 ‐ unterstützter Photokatalyse abgebaut. Die Zugabe von Ag ‐ Nanopartikeln ermöglicht die Identifizierung der Azoprodukte durch oberflächenverstärkte Resonanz ‐ Raman ‐ Spektroskopie und beschleunigt die photokatalytische Zersetzung. [ABSTRACT FROM AUTHOR]

Innentitelbild: Mn-O Covalency Governs the Intrinsic Activity of Co-Mn Spinel Oxides for Boosted Peroxymonosulfate Activation (Angew. Keywords: bimetal; covalency; octahedron; peroxymonosulfate (PMS); spinel oxides EN bimetal covalency octahedron peroxymonosulfate (PMS) spinel oxides 2 2 1 12/24/20 20210104 NES 210104 B Bimetallische Spinelloxide b sind effiziente Katalysatoren für die Aktivierung von Peroxymonosulfat (PMS), der katalytische Mechanismus ist jedoch unklar. Co verstärkt die Mn-O-Kovalenz in der oktaedrischen Konfiguration von Co SB 3-x sb Mn SB x sb O SB 4 sb , was die Ladungstransferenergie der Mn SB Oh sb -PMS-Wechselwirkung senkt und die Mn SP VI sp /Mn SP III sp -Redoxzyklen drastisch beschleunigt. [Extracted from the article]