The chemical bulk reductive covalent functionalization of thin-layerb lack phosphorus (BP) using BP intercalation compounds has been developed. Through effective reductive activation, covalent functionalization of the charged BP by reaction with organic alkylh alides is achieved. Functionalization was extensively demonstrated by means of several spectroscopic techniques and DFT calculations;t he products showed higher functionalization degrees than those obtained by neutral routes.Since 2014, two-dimensional (2D) black phosphorus (BP) has attracted tremendous attention throughout the scientific community due to its high p-type charge carrier mobility and its tunable direct band gap. [1][2][3][4][5][6][7][8][9] In contrast to graphene,B P exhibits amarked puckering of the sp 3 structure,constituting atwo-dimensional s-only system, involving one lone electron pair at each Pa tom. Whereas its outstanding physical and materials properties have been intensively investigated, its chemistry remains almost unexplored. [10][11][12] Indeed, af irst series of noncovalent functionalization protocols has been reported, mainly focused on improving the intrinsic instability of BP against water and oxygen. [13][14][15][16][17] Beyond these approaches,t he covalent functionalization of the interface is one of the most promising routes for fine-tuning the chemical and physical properties of 2D nanomaterials. [18,19] In this sense,only afew recent reports on single-flake chemistry with diazonium salts, [20] and wet-chemistry on previously exfoliated flakes with nucleophiles [21][22][23] or carbon-free radicals [24] have been reported so far.This is probably due to the intrinsic low degree of reactivity of neutral BP towards these reactions and the difficulties associated with overcoming the huge van der Waals energy stored within aBPcrystal, thus blocking the direct functionalization of BP.A long this front, ab ulk wetchemical derivatization sequence remains to be found. Moreover, an unambiguous determination of the covalent binding and its influence in the chemical structure of the P-layers is required to systematically explore the characteristics of BP reactivity.To address these challenges we took advantage of the well-known reductive graphene chemistry using graphite intercalation compounds (GICs). [18,[25][26][27] As af irst success in this direction, we have recently reported the preparation of BP intercalation compounds (BPICs) with alkali metals (K and Na). [28] This paves the way for the exploration of the reductive route using activated negatively charged BP-ite nanosheets and electrophiles (E) as covalent reaction partners.Herein, we provide the first real proof for covalent binding in BP with alkyl halides using abattery of characterization techniques.F urthermore,d ensity functional theory (DFT) calculations were carried out to rationalize our results, providing adeep understanding of the covalent derivatization of BP.This thorough study reveals for the first time the lattice opening in BP,absent in graphene,which is a...

The only stable isomer of the higher fullerene C76 of D2 symmetry was isolated from carbon soot by the new and advanced extraction and chromatographic methods and processes. Characterization of the isolated C76-D2 was performed by the IR(KBr) and UV/VIS method in the absorption mode. All of the experimentally observed infrared and electronic absorption bands are in excellent agreement with the theoretical calculations for this fullerene. The molar absorptivity ε and the integrated molar absorptivity Ψ of the observed entire new series of various characteristic, both deconvoluted and convoluted IR absorption bands of the C76-D2 isomer, in different integration ranges were determined. In addition, the molar extinction coefficients of its UV/VIS absorption bands were determined. The obtained novel IR and UV/VIS spectroscopic parameters are significant for the quantitative assessment of C76-D2. All the presented data are important both for its qualitative and quantitative determination, either in natural resources on Earth and in space or in artificially synthesized materials, electronic and optical devices, optical limiters, sensors, polymers, solar cells, nanophotonic lenses, diagnostic and therapeutic agents, pharmaceutical substances, for targeted drug delivery, incorporation of metal atoms, in biomedical engineering, industry, applied optical science, batteries, catalysts and so forth.

Eine chemisch-reduktive Volumen-Funktionalisierung von dünnlagigem schwarzem Phosphor (BP) wurde unter Verwendung von BP-Interkalationsverbindungen entwickelt. Durche ffektive reduktive Aktivierung wurde die kovalente Funktionalisierung des geladenen BP mit Alkylhalogeniden erreicht. Die kovalente Funktionalisierung wurde umfassend mit mehreren spektroskopischen Methoden sowie DFT-Rechnungen nachgewiesen;e sl iegt ein hçherer Funktionalisierungsgrad als bei neutralen Funktionalisierungsreaktionen vor. Seit2014hatderzweidimensionale(2D)schwarzePhosphor(BP) wegen seiner hohen p-Typ-Ladungsträgermobilitätu nd seiner modifizierbaren, direkten Bandlücke große Aufmerksamkeit auf sich gezogen. [1][2][3][4][5][6][7][8][9] Im Unterschied zu Graphen besteht BP aus gewellten Schichten, die ausschließlich aus einem 2D-s-System gebildet werden und in denen jedes P-Atom ein freies Elektronenpaar aufweist. Während seine bemerkenswerten physikalischen und Materialeigenschaften bereits intensiv untersucht wurden, bleibt seine Chemie nahezu unerforscht. [10][11][12] Mittlerweile wurde eine erste Reihe von Vorschriften zur nicht-kovalenten Funktionalisierung verçffentlicht, die hauptsächlich darauf abzielen, die Instabilitätv on BP gegen Wasser und Sauerstoff zu verbessern. [13][14][15][16][17] Abgesehen von diesen Ansätzen gilt die kovalente Funktionalisierung der Oberfläche als eines der vielversprechendsten Konzepte zur Modifizierung der chemischen und physikalischen Eigenschaften von 2D-Nanomaterialien. [18,19] In diesem Sinne wurden bisher nur wenige Arbeiten, wie die Funktionalisierung einzelner Flocken mit Diazoniumsalzen [20] oder die nasschemische Funktionalisierung von zuvor hergestellten Flocken mit Nukleophilen [21][22][23] sowie mit freien Kohlenstoffradikalen, [24] publiziert. Der Grund hierfürl iegt wahrscheinlich in der niedrigen Reaktivitätv on neutralem BP bei diesen Reaktionen. In diesem Zusammenhang wird die direkte kovalente Funktionalisierung oftmals verhindert, da die BP-Schichten durch eine hohe Va n-der-Waals-Energie zusammengehalten werden. Ausd iesem Grund muss eine effektive nasschemische Funktionalisierungssequenz erst noch gefunden werden. Eine eindeutige Bestimmung der kovalenten Bindung und ihres Einflusses auf die chemische Struktur der BP-Schichten ist zudem zur systematischen Untersuchung der Reaktivitätvon BP erforderlich.Wirh aben uns die bekannte reduktive Graphenchemie, die auf der Verwendung von Graphit-Interkalationsverbindungen (GICs) beruht, zunutze gemacht. [18,[25][26][27] Als ersten Erfolg in dieser Richtung haben wir 2017 die Herstellung von BP-Interkalationsverbindungen (BPICs) mit Alkalimetallen (K und Na) beschrieben. [28] Dies ebnet den Wegz ur Erforschung der reduktiven Route basierend auf der Nutzung von

Two‐dimensional (2D) black phosphorus (BP) represents one of the most appealing 2D materials due to its electronic, optical, and chemical properties. Many strategies have been pursued to face its environmental instability, covalent functionalization being one of the most promising. However, the extremely low functionalization degrees and the limitations in proving the nature of the covalent functionalization still represent challenges in many of these sheet architectures reported to date. Here we shine light on the structural evolution of 2D‐BP upon the addition of electrophilic diazonium salts. We demonstrated the absence of covalent functionalization in both the neutral and the reductive routes, observing in the latter case an unexpected interface conversion of BP to red phosphorus (RP), as characterized by Raman, 31P‐MAS NMR, and X‐ray photoelectron spectroscopies (XPS). Furthermore, thermogravimetric analysis coupled to gas chromatography and mass spectrometry (TG‐GC‐MS), as well as electron paramagnetic resonance (EPR) gave insights into the potential underlying radical mechanism, suggesting a Sandmeyer‐like reaction.