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The development of advanced microelectronics requires new device architecture and multi‐functionality. Low‐dimensional material is considered as a powerful candidate to construct new devices. In this work, a flexible memristor is fabricated utilizing 2D cadmium phosphorus trichalcogenide nanosheets as the functional layer. The memristor exhibits excellent resistive switching performance under different radius and over 103 bending times. The device mechanism is systematically investigated, and the synaptic plasticity including paired‐pulse facilitation and spiking timing‐dependent plasticity are further observed. Furthermore, based on the linearly conductance modulation capacity of the flexible memristor, the applications on decimal operation are explored, that the addition, subtraction, multiplication, and division of decimal calculation are successfully achieved. These results demonstrate the potential of metal phosphorus trichalcogenide in novel flexible neuromorphic devices, which accelerate the application process of neuromorphic computing. [ABSTRACT FROM AUTHOR]

Chronic obstructive pulmonary disease (COPD) is an intractable disease involving a sticky mucus layer and nanoagents with mucus‐penetrating capability offer a new way to deliver drugs. However, drug release from nanovehicles requires optimization to enhance the therapeutic effects of COPD therapy. Herein, black phosphorus quantum dots (BPQDs) are combined with PEGylated chitosan nanospheres containing the antibiotic amikacin (termed PEG@CS/BPQDs‐AM NPs). As a drug‐delivery system, the hydrophilicity of PEG and positive charge of CS facilitate the penetration of nanovehicles through the mucus layer. The nanovehicles then adhere to the mucous membrane. Furthermore, the BPQDs degrade rapidly into nontoxic PO43− and acidic H+, thereby promoting the dissociation of PEGylated CS nanospheres, accelerating the release of AM, decreasing the vitality of biofilms for ease of eradication. Our results reveal that drug delivery mediated by BPQDs is a feasible and desirable strategy for precision medicine and promising for the clinical therapy of COPD. [ABSTRACT FROM AUTHOR]

Biodegradable inorganic nanomaterials have opened new perspectives for cancer therapy due to their inherent anticancer activity. Black phosphorus nanosheets (BPs) with their unique bioactivity have recently been identified as promising cancer therapeutic agents but their application is hampered by the difficulty in surface functionalization. Herein, an in situ calcium phosphate (CaP) mineralization strategy is described to enhance the anticancer activity of BPs. By using BPs as the phosphate sources and growth templates, the synthesized CaP‐mineralized BPs (CaBPs) retain the intrinsic properties of BPs and at the same time have high loading capacities for various fluorophores to enable effective bioimaging and tracing. Compared to BPs, CaBPs exhibit enhanced and selective anticancer bioactivity due to the improved pH‐responsive degradation behavior and intracellular Ca2+ overloading in cancer cells. Furthermore, CaBPs specifically target mitochondria and cause structural damage, thus leading to mitochondria‐mediated apoptosis in cancer cells. After intravenous injection, CaBPs target orthotopic breast cancer cells to inhibit tumor growth without giving rise to adverse effects or toxicity. The results demonstrate the great potential of CaBPs as targeted anticancer agents and the CaP mineralization approach provides a versatile surface functionalization strategy for nanotherapeutic agents. [ABSTRACT FROM AUTHOR]

The photochemical activity of black phosphorus (BP) in near‐infrared (NIR) light controlled in situ biomineralization is investigated. Owing to the excellent NIR absorption, irradiation with NIR light not only promotes degradation of BP into PO43−, but also enhances the chemical activity to accelerate the reaction between PO43− and Ca2+ and promote in situ biomineralization. Mineralization of hydrogels is demonstrated by the preparation of BP incorporated hydrogel (BP@Hydrogel) which delivers greatly improved biomineralization performance under NIR illumination. The biomineralization process which can be controlled by modulating the light irradiation time and location has a high potential in controlling the mechanical properties and osteoinductive ability in tissue engineering. This study also provides insights into the degradation, photochemical activity, and new biological/biomedical applications of BP. [ABSTRACT FROM AUTHOR]

Efficient production of ammonia using environmentally friendly techniques under ambient conditions is crucial to renewable energy storage and industrial applications, and catalysts with new reaction pathways are highly desirable. In this work, black phosphorus (BP) is used as a metal‐free 2D catalyst for the photoelectrochemical (PEC) nitrogen reduction reaction (NRR). The electrode is fabricated by layer‐by‐layer assembly of BP nanosheets on an indium tin oxide substrate. The PEC NRR activity in the N2 saturated aqueous electrolyte without a sacrificial agent is excellent, as exemplified by an ammonia yield rate of 102.4 µg h−1 mgcat.−1 and Faradaic efficiency of 23.3% at −0.4 V, which are the best among nonmetal catalysts for synthesis of ammonia by photocatalysis and electrocatalysis. Furthermore, the BP electrode shows excellent stability after 6 consecutive cycles. The excellent PEC catalytic properties are attributed to the light excitation enhanced electrocatalytic process and that the external bias promoted photocatalytic process improves ammonia production synergistically. The results not only demonstrate the great potential of BP in PEC catalysis, but also identify a promising technique to produce ammonia under ambient conditions using solar energy and electric energy. [ABSTRACT FROM AUTHOR]

Black phosphorus (BP) promises high‐performance humidity sensing, due to its unique electrical, mechanical, and surface properties. Different from traditional transistor‐based BP humidity sensors, herein, an all‐fiber sensing strategy is proposed by integrating BP nanosheets with etched single‐mode fiber (ESMF). The experiments show that transmitted light in the ESMF can be effectively modulated by the coated BP nanosheets as relative humidity varies from 35% to 80%. Due to the combination of unique sensing characteristics of BP materials with a high sensitivity of optical modulation strategy, highly responsive humidity sensing is achieved with the response time as fast as 7 ms. This work demonstrates a BP‐based all‐optical sensing platform not only for high‐performance humidity sensing, but also for opening up new opportunities for many potential vapor/gas sensing applications in the fields of biomedicine and chemistry. [ABSTRACT FROM AUTHOR]

Abstract: Photothermal therapy (PTT) is a fledgling therapeutic strategy for cancer treatment with minimal invasiveness but clinical adoption has been stifled by concerns such as insufficient biodegradability of the PTT agents and lack of an efficient delivery system. Here, black phosphorus (BP) nanosheets are incorporated with a thermosensitive hydrogel [poly( d, l‐lactide)‐poly(ethylene glycol)‐poly( d, l‐lactide) (PDLLA‐PEG‐PDLLA: PLEL)] to produce a new PTT system for postoperative treatment of cancer. The BP@PLEL hydrogel exhibits excellent near infrared (NIR) photothermal performance and a rapid NIR‐induced sol–gel transition as well as good biodegradability and biocompatibility in vitro and in vivo. Based on these merits, an in vivo PTT postoperative treatment strategy is established. Under NIR irradiation, the sprayed BP@PLEL hydrogel enables rapid gelation forming a gelled membrane on wounds and offers high PTT efficacy to eliminate residual tumor tissues after tumor removal surgery. Furthermore, the good photothermal antibacterial performance prevents infection and this efficient and biodegradable PTT system is very promising in postoperative treatment of cancer. [ABSTRACT FROM AUTHOR]

Flexible and robust memristors with controllable resistance‐switching characteristics are important to neuromorphic computing. However, the nanomaterials‐based, solution‐processed resistance switching layer usually has poor reliability and tunability due to uneven morphology and invariable surface properties. Herein, phosphorylated graphene nanoflakes (phos‐GPs) are synthesized for high‐performance solution‐processed flexible memristors. In situ conductive atomic force microscopy reveals that the tightly stacked uniform nanoflakes and modified phosphorate groups jointly reduce the formation barrier of the conductive filaments. Furthermore, phosphorylation gives rise to surface silver ion coordination leading to enhanced radial growth of the conductive filaments. The memristor shows volatile characteristics in the Ag/phos‐GPs/ITO architecture and exhibits non‐volatile properties in the Ag/Ag+‐(phos‐GPs)/ITO structure. Both types of memristors display consistent I‐‐V curves during long‐term cycling and under repetitive mechanical bending, in addition to excellent synaptic plasticity. Moreover, ultrasmall nonlinearity is observed from non‐volatile long‐term synaptic potentiation and depression. By utilizing the tunable artificial synapses, the processes of memory‐forgetting and re‐recognition are simulated, and the image recognition tasks are accomplished by the artificial neural networks. [ABSTRACT FROM AUTHOR]

Photoelectrochemical Ammonia Synthesis: Photoelectrochemical Synthesis of Ammonia with Black Phosphorus (Adv. Funct. Keywords: 2D materials; black phosphorus; nitrogen reduction reaction; photoelectrochemical catalysis; synthesis of ammonia EN 2D materials black phosphorus nitrogen reduction reaction photoelectrochemical catalysis synthesis of ammonia 1 1 1 06/13/20 20200615 NES 200615 Black phosphorus (BP) is developed as a highly efficient metal-free photoelectrochemical (PEC) ammonia synthesis catalyst for the first time. 2D materials, black phosphorus, nitrogen reduction reaction, photoelectrochemical catalysis, synthesis of ammonia. [Extracted from the article]

The rapid development of the semiconductor industry calls for the exploration of novel semiconductors to cater to modern technical and commercial needs. Recently, black phosphorus (BP) has emerged as a new class of 2D semiconducting material and has attracted intensive research attention. The high carrier mobility and tunable direct bandgap of BP deliver great promise in photonic and optoelectronic device applications. Furthermore, the unique intrinsic anisotropy arising from the puckered structure can be exploited in the design of new devices. This review briefly introduces the history of BP and puts emphasis on recent advances pertaining to its optical properties and applications in the photonic and optoelectronic fields. From the perspective of mass production and practical use of BP, some of the research challenges and opportunities are discussed. [ABSTRACT FROM AUTHOR]

2D materials with large specific surface area and robust mechanical properties are appropriate for electrocatalysis. However, the unsatisfactory adsorption energy and limited active sites restrict their commercial application. Herein, a facile and rapid electrochemical strategy enabling synchronous exfoliation and doping is designed to directly synthesize metal‐doped 2D materials from the bulk crystals. By using black phosphorus as a model, various metal doped phosphorene such as BP(Co), BP(Mo), and BP(Ni) is obtained, and a synergistic synthesis mechanism is proposed. Notably, the dopant introduces electronic band transformation, charge redistribution, and state occupation confirmed by density functional theory calculations. Owing to the enhanced electro‐conductivity, abundant metal‐P active sites, and optimized adsorption energy by doping, the BP(metal) exhibits enhanced hydrogen evolution reaction activities and stability in comparison to the bare phosphorene. Particularly, BP(Co) presents highest activity with a potential of 0.294 V at 10 mA cm−2 (the current density is normalized with electrochemical surface area by using a double‐layer capacitance method). This study provides new access to synthesize highly efficient electrocatalysts, and also enriches the structure modulation means for layered 2D materials. [ABSTRACT FROM AUTHOR]

An efficient metal‐free photocatalyst composed of black phosphorus (BP) and graphitic carbon nitride (CN) is prepared on a large scale by ball milling. Using economical urea and red phosphorus (RP) as the raw materials, the estimated materials cost of BP/CN is 0.235 Euro per gram. The BP/CN heterostructure shows efficient charge separation and possesses abundant active sites, giving rise to excellent photocatalytic H2 evolution and rhodamine B (RhB) degradation efficiency. Without using a co‐catalyst, the metal‐free BP/CN emits H2 consistently at a rate as large as 786 µmol h−1 g−1 and RhB is decomposed in merely 25 min during visible‐light irradiation. The corresponding electron/hole transfer and catalytic mechanisms are analyzed and described. The efficient metal‐free catalyst is promising in visible‐light photocatalysis and the simple ball‐milling synthetic method can be readily scaled up. Metal‐free black phosphorus/graphitic carbon nitride (BP/CN) heterostructures are prepared by ball milling using economical urea and red phosphorus as the raw materials. Without using a co‐catalyst, BP/CN emits H2 consistently at a rate as large as 786 µmol h−1 g−1 and rhodamine B is decomposed in merely 25 min, demonstrating excellent performances in visible‐light photocatalysis. [ABSTRACT FROM AUTHOR]

Using economical urea and red phosphorus as the only raw materials, a low‐cost black phosphorus/graphitic carbon nitride (BP/CN) heterostructure is prepared on a large scale by ball milling in article number 1801321 by Xue‐Feng Yu and co‐workers. The metal‐free heterostructure acts as an efficient and stable photocatalyst for both hydrogen evolution and dye degradation. [ABSTRACT FROM AUTHOR]

A near-infrared (NIR) light-triggered drug delivery platform is produced by incorporating SrCl 2 and BP nanosheets (BPs) into poly(lactic- co -glycolic acid) (PLGA) for bone regeneration. The fabricated BP-SrCl 2 /PLGA microspheres show efficient NIR absorption and photothermal effects due to the BPs. The NIR-triggered release behavior of Sr 2+ by flawing the PLGA shells is investigated and the microspheres exhibit excellent cell viability and biodegradability. Implantation of the BP-SrCl 2 /PLGA microspheres into a rat femoral defect demonstrates good tissue compatibility and excellent bone regeneration capacity under NIR light irradiation. Our study indicates that local release of Sr 2+ at optimal time periods controlled by NIR irradiation improves bone regeneration significantly and this NIR-triggered drug delivery system composed of BPs is suitable for therapies requiring precise control at specific time. [ABSTRACT FROM AUTHOR]