Inspired by the multiple functions of natural multienzyme systems, a new kind of hybrid nanosheet is designed and synthesized, i.e., ultrasmall Au nanoparticles (NPs) grown on 2D metalloporphyrinic ...metal‐organic framework (MOF) nanosheets. Since 2D metalloporphyrinic MOF nanosheets can act as the peroxidase mimics and Au NPs can serve as artificial glucose oxidase, the hybrid nanosheets are used to mimic the natural enzymes and catalyze the cascade reactions. Furthermore, the synthesized hybrid nanosheets are used to detect biomolecules, such as glucose. This study paves a new avenue to design nanomaterial‐based biomimetic catalysts with multiple complex functions.
Inspired by the multiple functions of natural multienzyme systems, hybrid nanosheets are designed and synthesized, i.e., ultrasmall Au nanoparticles are grown on 2D metalloporphyrinic metal‐organic framework nanosheets. Since nanosheets can act as the peroxidase mimics and Au nanoparticles can serve as artificial glucose oxidase, the hybrid nanosheets are used to mimic the natural enzymes and catalyze the cascade reactions.
Nanostructured transition metal dichalcogenides (TMDs) are proven to be efficient and robust earth‐abundant electrocatalysts to potentially replace precious platinum‐based catalysts for the hydrogen ...evolution reaction (HER). However, the catalytic efficiency of reported TMD catalysts is still limited by their low‐density active sites, low conductivity, and/or uncleaned surface. Herein, a general and facile method is reported for high‐yield, large‐scale production of water‐dispersed, ultrasmall‐sized, high‐percentage 1T‐phase, single‐layer TMD nanodots with high‐density active edge sites and clean surface, including MoS2, WS2, MoSe2, Mo0.5W0.5S2, and MoSSe, which exhibit much enhanced electrochemical HER performances as compared to their corresponding nanosheets. Impressively, the obtained MoSSe nanodots achieve a low overpotential of −140 mV at current density of 10 mA cm−2, a Tafel slope of 40 mV dec−1, and excellent long‐term durability. The experimental and theoretical results suggest that the excellent catalytic activity of MoSSe nanodots is attributed to the high‐density active edge sites, high‐percentage metallic 1T phase, alloying effect and basal‐plane Se‐vacancy. This work provides a universal and effective way toward the synthesis of TMD nanostructures with abundant active sites for electrocatalysis, which can also be used for other applications such as batteries, sensors, and bioimaging.
A general and facile method is developed for high‐yield, large‐scale production of water‐dispersed, ultrasmall, high‐percentage 1T‐phase, single‐layer transition metal dichalcogenide nanodots with high‐density active edge sites and clean surface, including MoS2, WS2, MoSe2, Mo0.5W0.5S2, and MoSSe, which exhibit much enhanced electrochemical hydrogen evolution reaction performances as compared to their corresponding nanosheets.
Rational design and synthesis of heterostructures based on transition metal dichalcogenides (TMDs) have attracted increasing interests because of their promising applications in electronics, ...catalysis, etc. However, the construction of epitaxial heterostructures with an interface at the edges of TMD nanosheets (NSs) still remains a great challenge. Here, we report a strategy for controlled synthesis of a new type of heterostructure in which TMD NSs, including MoS2 and MoSe2, vertically grow along the longitudinal direction of one-dimensional (1D) Cu2–x S nanowires (NWs) in an epitaxial manner. The obtained Cu2–x S-TMD heterostructures with tunable loading amount and lateral size of TMD NSs are achieved by the consecutive growth of TMD NSs on Cu2–x S NWs through gradual injection of chalcogen precursors. After cation exchange of Cu in Cu2–x S-TMD heterostructures with Cd, the obtained CdS–MoS2 heterostructures retained their original architectures. Compared to the pure CdS NWs, the CdS–MoS2 heterostructures with 7.7 wt % loading of MoS2 NSs exhibit the best performance in the photocatalytic hydrogen evolution reaction with a H2 production rate up to 4647 μmol·h–1·g–1, about 58 times that catalyzed with pure CdS NWs. Our synthetic strategy opens up a new way for the controlled synthesis of TMD-based heterostructures, which could have various promising applications.
The incorporation of metal–organic frameworks (MOFs) into membrane‐shaped architectures is of great importance for practical applications. The currently synthesized MOF‐based membranes show many ...disadvantages, such as poor compatibility, low dispersity, and instability, which severely limit their utility. Herein, we present a general, facile, and robust approach for the synthesis of MOF‐based composite membranes through the in situ growth of MOF plates in the channels of anodized aluminum oxide (AAO) membranes. After being used as catalysis reactors, they exhibit high catalytic performance and stability in the Knoevenagel condensation reaction. The high catalytic performance might be attributed to the intrinsic structure of MOF‐based composite membranes, which can remove the products from the reaction zone quickly, and prevent the aggregation and loss of catalysts during reaction and recycling process.
A MOF reactor: A general, facile, and robust approach is presented for the preparation of MOF‐based composite membranes through the in situ growth of MOF plates in the channels of anodized aluminum oxide membranes. The MOF‐based composite membranes were used as membrane catalysis reactors, and showed excellent catalytic performance and stability in the Knoevenagel condensation.
In this work, ZnO nanorods surface was functionalized with poly(1-methoxy-4-(2-ethylhexyloxy)-p-phenylenevinylene) (MEH-PPV), offering a hybrid nanocomposite (MEH-PPV∼ZnO) that was directly applied ...for the preparation of active layer in hybrids photovoltaic devices. X-ray photoelectron spectroscopy (XPS), transmission electron microscopy (TEM) and photophysical properties showed that the conjugated polymer chains intimately contact with the inorganic semiconductors. The performance of the resulting photovoltaic devices was investigated by current–voltage (
J–
V) characteristics and intensity-modulated photovoltage spectroscopy (IMVS). The photovoltaic performance was greatly enhanced via direct application of the nanocomposites as the active layer in photovoltaic devices, giving an optimized device performance of a short-circuit current density of 0.19
mA/cm
2, an open-circuit voltage of 0.59
V and a fill factor of 0.43, with a power conversion efficiency of about 0.30% under 470
nm monochromatic illumination (15.8
mW/cm
2) that was 50% higher than that of the device based on the simple blend of two components. In addition, intensity-modulated photovoltage spectroscopy (IMVS) response curves revealed that a longer electron lifetime in the MEH-PPV∼ZnO bulk heterojunction photovoltaic devices leads to a higher open-circuit voltage of the devices.
Since the discovery of mechanically exfoliated graphene in 2004, research on ultrathin two-dimensional (2D) nanomaterials has grown exponentially in the fields of condensed matter physics, material ...science, chemistry, and nanotechnology. Highlighting their compelling physical, chemical, electronic, and optical properties, as well as their various potential applications, in this Review, we summarize the state-of-art progress on the ultrathin 2D nanomaterials with a particular emphasis on their recent advances. First, we introduce the unique advances on ultrathin 2D nanomaterials, followed by the description of their composition and crystal structures. The assortments of their synthetic methods are then summarized, including insights on their advantages and limitations, alongside some recommendations on suitable characterization techniques. We also discuss in detail the utilization of these ultrathin 2D nanomaterials for wide ranges of potential applications among the electronics/optoelectronics, electrocatalysis, batteries, supercapacitors, solar cells, photocatalysis, and sensing platforms. Finally, the challenges and outlooks in this promising field are featured on the basis of its current development.
The layered transition metal dichalcogenides (TMDs) and transition metal phosphides are low-cost, earth-abundant, and robust electrocatalysts for hydrogen evolution reaction (HER). Integrating them ...into hybrid nanostructures is potentially promising to further boost the catalytic activity toward HER based on their synergistic effects. Herein, we report a general method for the synthesis of a series of MoSe
2
-based hybrid nanostructures, including MoSe
2
-Ni
2
P, MoSe
2
-Co
2
P, MoSe
2
-Ni, MoSe
2
-Co, and MoSe
2
-NiS, by postgrowth of Ni
2
P, Co
2
P, Ni, Co, and NiS nanostructures on the presynthesized MoSe
2
nanosheet-assembled nanospheres, respectively, via a colloidal synthesis method. As a proof-of-concept application, the as-synthesized hybrid nanostructures are used as electrocatalysts for HER, exhibiting high activity and stability in acidic media. Among them, the MoSe
2
-Co
2
P composite shows the highest HER activity with an overpotential of 167 mV at 10 mA cm
−2
.
A novel route is presented for preparation of poly(1-methoxy-4-(2-ethylhexyloxy)-
p
-phenylenevinylene) (MEH-PPV)-functionalized TiO
2
nanoparticles (NPs), resulting in a hybrid nanocomposite ...(MEH-PPV~TiO
2
NPs). Thermogravimetric analysis (TGA) was used to evaluate the exact content of TiO
2
nanoparticles in the MEH-PPV~TiO
2
nanocomposites. Fourier-transform infrared (FT-IR) spectroscopy, transmission electron microscopy (TEM), and photophysical properties showed that the conjugated polymer chains intimately contact with the inorganic semiconductors. The performance of photovoltaic devices based on the MEH-PPV~TiO
2
NPs nanocomposite was investigated by current–voltage (
J
–
V
) characteristics and intensity-modulated photovoltage spectroscopy (IMVS). Device performance was greatly improved by direct application of MEH-PPV~TiO
2
NPs nanocomposites as the active layer as compared with devices with simply blended counterparts (MEH-PPV/TiO
2
NPs). In addition, IMVS revealed that the longer electron lifetime was accompanied by higher open-circuit voltage in the MEH-PPV~TiO
2
NPs devices.
The deterioration of water resources due to oil pollution, arising from oil spills, industrial oily wastewater discharge, etc., urgently requires the development of novel functional materials for ...highly efficient water remediation. Recently, superhydrophilic and underwater superoleophobic materials have drawn significant attention due to their low oil adhesion and selective oil/water separation. However, it is still a challenge to prepare low‐cost, environmentally friendly, and multifunctional materials with superhydrophilicity and underwater superoleophobicity, which can be stably used for oil/water separation under harsh working conditions. Here, the preparation of nanofiber‐based meshes derived from waste glass through a green and sustainable route is demonstrated. The resulting meshes exhibit excellent performance in the selective separation of a wide range of oil/water mixtures. Importantly, these meshes can also maintain the superwetting property and high oil/water separation efficiency under various harsh conditions. Furthermore, the as‐prepared mesh can remove water‐soluble contaminants simultaneously during the oil/water separation process, leading to multifunctional water purification. The low‐cost and environmentally friendly fabrication, harsh‐environment resistance, and multifunctional characteristics make these nanofiber‐based meshes promising toward oil/water separation under practical conditions.
Superhydrophilic and underwater superoleophobic meshes are prepared using waste glass as starting material through a sustainable route. The as‐prepared meshes show highly efficient performance in selective oil/water separation. Importantly, the meshes also show excellent resistance against many harsh environments, as well as the multifunctional water remediation capability, making them highly promising toward practical applications.
In this paper, we reported an improved preparation of 1-methyl-3-propylimidazolium iodide (MPII), which was the alkylation reaction of
n-propyl iodide and 1-methylimidazole under solvent-free ...conditions by Teflon-lined, stainless autoclaves. It was shown that the resulting MPII was high pure, the conversion rate of 1-methylimidazole was close to 100% and the procedure was simple and eco-friendly. Moreover, the apparent diffusion coefficients of triiodide and iodide in the mixture with different ratios of MPII and 3-methoxypropionitrile were demonstrated by cyclic voltammetry using a Pt ultramicroelectrode. The dye-sensitized solar cells with the electrolyte, which was composed of 0.13
M I
2, 0.10
M LiI, 0.50
M 4-
tert-butylpyrdine in the mixture of 3-methoxypropionitrile and MPII (weight ratio 0.65:1), gave short circuit photocurrent density of 14.82
mA/cm
2, open-circuit voltage of 0.69
V, and fill factor of 0.66, corresponding to the photoelectric conversion efficiency of 6.73% at the illumination (AM 1.5, 100
mW/cm
2).
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