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.
Black phosphorus (BP) is developed as a metal‐free 2D catalyst for the photoelectrochemical synthesis of ammonia at ambient conditions. The ammonia yield rate and Faradaic efficiency in acid electrolyte is determined as 102.4 µg h−1 mgcat.−1 and 23.3%, respectively. The excellent catalytic properties of BP are attributed to the synergistic effects of photoexcitation enhanced electrocatalysis and external bias promoted photocatalysis.
Harnessing the physiochemical properties and enzymatic activities of nanozymes will provide new insights for disease theranostics. Herein, a novel carbon dot (C‐dot) superoxide dismutase (SOD) ...nanozyme that exhibits red fluorescence with emission wavelength of 683 nm and shows high SOD‐like activity of >4000 U mg−1 is reported, which presents the great potential for imaging the biodistribution of nanozyme itself in vivo and ameliorating acute lung injury. Through surface modifications, the mechanism of C‐dot SOD nanozyme activity is revealed to be relied on their surface functional groups which bind with superoxide radicals, promote the electron transfer between C‐dots and superoxide radicals, and finally accelerate the dismutation of superoxide radicals. The absolute quantum yield of ≈14% of red fluorescence C‐dot nanozyme endow it bioimaging in vitro and in vivo. Moreover, the C‐dot nanozyme effectively enters the cells, accumulates at mitochondria, and protects living cells from oxidative damage by scavenging reactive oxygen species (ROS) and reducing the levels of pro‐inflammatory factors. Importantly, in vivo animal experiments demonstrate the accumulation of C‐dots in injure lung and therapeutic effect of C‐dot nanozyme toward acute lung injury in mice. The red fluorescent C‐dot SOD nanozyme shows great potential for in vivo bioimaging and management of ROS‐related diseases.
Red emissive carbon dot nanozyme with high superoxide dismutase (SOD)‐like activity over 4000 U mg−1 is developed. The SOD nanozyme activity is revealed to be relied on their surface functional groups which capture O2•– and then promote the electron transfer between O2•– and π‐system of carbon dot. The C‐dot SOD nanozyme shows great potential in bioimaging and ameliorating acute lung injury.
Modulation of the electronic structure of metal catalysts is an effective approach to optimize the electrocatalytic activity. Herein, we show a surprisingly strong activation effect of black ...phosphorus (BP) on platinum (Pt) catalysts to give greatly enhanced catalytic activity in the hydrogen evolution reaction (HER). The unique and negative binding energy between BP and Pt leads to spontaneous formation of Pt‐P bonds producing strong synergistic ligand effects on the Pt nanoparticles. No Pt‐P bonds are formed with red phosphorus which is another allotrope of P. By controlling the number of Pt‐P bonds, 3.5‐fold enhancement in the HER activity can be achieved from the BP‐activated Pt catalyst and the activity is 6.1 times higher than that of the state‐of‐the‐art commercial Pt/C catalyst. The BP‐activated Pt catalyst exhibits a current density of 82.89 mA cm−2 with only 1 μg of Pt in 1 m KOH at an overpotential of 70 mV.
Back in black: Surprisingly strong activation effects of black phosphorus (BP) on Pt catalysts and subsequent modulation the surface electronic structure of Pt result in greatly enhanced catalytic activity in the hydrogen evolution reaction (HER).
Black phosphorus (BP), a burgeoning elemental 2D semiconductor, has aroused increasing scientific and technological interest, especially as a channel material in field‐effect transistors (FETs). ...However, the intrinsic instability of BP causes practical concern and the transistor performance must also be improved. Here, the use of metal‐ion modification to enhance both the stability and transistor performance of BP sheets is described. Ag+ spontaneously adsorbed on the BP surface via cation–π interactions passivates the lone‐pair electrons of P thereby rendering BP more stable in air. Consequently, the Ag+‐modified BP FET shows greatly enhanced hole mobility from 796 to 1666 cm2 V−1 s−1 and ON/OFF ratio from 5.9 × 104 to 2.6 × 106. The mechanisms pertaining to the enhanced stability and transistor performance are discussed and the strategy can be extended to other metal ions such as Fe3+, Mg2+, and Hg2+. Such stable and high‐performance BP transistors are crucial to electronic and optoelectronic devices. The stability and semiconducting properties of BP sheets can be enhanced tremendously by this novel strategy.
A simple and effective metal‐ion modification strategy based on cation–π interactions is applied to black phosphorus to enhance both its air stability and its transistor performance. Such stable and high‐performance black‐phosphorus transistors, which are enhanced tremendously by this novel strategy, have large potential in electronic and optoelectronic devices.
Black phosphorus quantum dots coordinated with a sulfonic ester of the titanium ligand are prepared and exhibit enhanced stability. In vitro and in vivo photoacoustic imaging applications demonstrate ...that the quantum dots can efficiently accumulate inside the tumor producing tumor profiles with high spatial resolution, demonstrating their potential as an efficient agent for photoacoustic imaging.
The practical application of layered black phosphorus (LBP) is compromised by fast decomposition in the presence of H2O and/or O2. The role of H2O is controversial. Herein, we propose a hydroxide ion ...(OH−)‐initiated degradation mechanism for LBP to elucidate the role of H2O. We found that LBP degraded faster in alkaline solutions than in neutral or acidic solutions with or without O2. Degradation rates of LBP increased linearly from pH 4 to 10. Density functional theory (DFT) calculations showed that OH− initiated the decomposition of LBP through breaking the P−P bond and forming a P−O bond. The detection of hypophosphite, generated from OH− reacting with P atoms, confirmed the hypothesis. Protons acted in a way distinctive from OH−, by inducing deposition/aggregation or forming a cation–π layer to protect LBP from degradation. This work reveals the degradation mechanism of LBP and thus facilitates the development of effective stabilization technologies.
Back in black: A ‐The degradation of layered black phosphorus (LBP) is revealed to be initiated by hydroxide ions (OH−). DFT calculations and experiments, shown OH− plays a more significant role than H2O in breaking the P−P bonds. In fact, protons acted as a protector to prevent LBP from degrading.
Owing to the rapid developments to improve the accuracy and efficiency of both experimental and computational investigative methodologies, the massive amounts of data generated have led the field of ...materials science into the fourth paradigm of data‐driven scientific research. This transition requires the development of authoritative and up‐to‐date frameworks for data‐driven approaches for material innovation. A critical discussion on the current advances in the data‐driven discovery of materials with a focus on frameworks, machine‐learning algorithms, material‐specific databases, descriptors, and targeted applications in the field of inorganic materials is presented. Frameworks for rationalizing data‐driven material innovation are described, and a critical review of essential subdisciplines is presented, including: i) advanced data‐intensive strategies and machine‐learning algorithms; ii) material databases and related tools and platforms for data generation and management; iii) commonly used molecular descriptors used in data‐driven processes. Furthermore, an in‐depth discussion on the broad applications of material innovation, such as energy conversion and storage, environmental decontamination, flexible electronics, optoelectronics, superconductors, metallic glasses, and magnetic materials, is provided. Finally, how these subdisciplines (with insights into the synergy of materials science, computational tools, and mathematics) support data‐driven paradigms is outlined, and the opportunities and challenges in data‐driven material innovation are highlighted.
The recent advances, strategies, insights, and challenges of data‐driven‐based innovations and applications in material science are discussed. Essential subdisciplines, including framework, machine‐learning algorithms, available chemical databases, commonly used key descriptors, and innovations and applications based on their synergy, are reviewed.
A titanium sulfonate ligand is synthesized for surface coordination of black phosphorus (BP). In contrast to serious degradation observed from the bare BP, the BP after surface coordination exhibits ...excellent stability during dispersion in water and exposure to air for a long period of time, thereby significantly extending the lifetime and spurring broader application of BP.
A titanium sulfonate ligand was synthesized and used to coordinate with black phosphorus (BP). In contrast to the serious degradation observed in bare BP, the BP after surface coordination exhibited excellent stability during dispersion in water and exposure to air for a long period of time, significantly extending the lifetime and spurring broader applications of BP.
Ultrasmall black phosphorus quantum dots (BPQDs) with an average size of 2.1 ± 0.9 nm are synthesized by using a solvothermal method in a N‐methyl‐2‐pyrrolidone solution. Verified by femto‐second ...laser Z‐scan measurement, BPQDs exhibit excellent nonlinear optical response with a modulation depth of about 36% and a saturable intensity of about 3.3 GW cm−2. By using BPQDs as optical saturable absorber, the ultrashort pulse with a pulse duration of about 1.08 ps centered at a wavelength of 1567.5 nm is generated in mode‐locked fiber laser. These results suggest that BPQDs may be developed as another kind of promising nanomaterial for ultrafast photonics.
A solvothermal synthesis is decribed to produce ultrasmall black phosphorus quantum dots (BPQDs) in large scale. BPQDs exhibit excellent nonlinear optical response and are used as optical saturable absorber. The ultrashort pulse with a pulse duration of about 1.08 ps centered at a wavelength of 1567.5 nm is generated by a mode‐locked fiber laser.
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.
A sprayable and biodegradable photothermal therapy (PTT) system composed of a thermosensitive hydrogel incorporated with black phosphorus (BP) nanosheets is presented for post‐surgical treatment of cancer. The obtained hydrogel enables rapid gelation and offers high PTT efficacy to eliminate residual tumor after surgery. This efficient and biodegradable PTT system is very promising in the postoperative treatment of cancer.
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