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A long-range surface plasmon resonance substrate, which consists of a gold nanoring cavity array built on a refractive index-symmetric spacer layer and an Au mirror, facilitates much higher RI sensitivity and a narrower FWHM than a conventional SPR substrate.

Rechargeable magnesium batteries (RMBs) are considered as potential energy storage devices due to their high volumetric specific capacity, good safety, as well as source abundance. Despite extensive efforts devoted to constructing an efficient magnesium battery system, the sluggish Mg

Solar-powered CO2 conversion represents a promising green and sustainable approach for achieving a carbon-neutral economy. However, the rational design of a wide-spectrum sunlight-driven catalysis system for effective CO2 reduction is an ongoing challenge. Herein, we report the preparation of a rhodium/aluminum (Rh/Al) nanoantenna photothermal catalyst that can utilize a broad range of sunlight (from ultraviolet to the near-infrared region) for highly efficient CO2 methanation, achieving a high CH4 selectivity of nearly 100% and an unprecedented CH4 productivity of 550 mmol·g-1·h-1 under concentrated simulated solar irradiation (11.3 W·cm-2). Detailed control experiment results verified that the CO2 methanation process was facilitated by the localized surface plasmonic resonance and nanoantenna effects of the Rh/Al nanostructure under light irradiation. In operando temperature-programmed Fourier transform infrared spectroscopy confirmed that CO2 methanation on the Rh/Al nanoantenna catalyst was a multistep reaction with CO as a key intermediate. The design of a wide-spectrum solar-driven photothermal catalyst provides a feasible strategy for boosting CO2-to-fuel conversion.

The construction of low-cost, highly efficient, and stable electrocatalysts is a significant challenge for the hydrogen evolution reaction (HER) and oxygen evolution reaction (OER). Herein, we report a facile strategy to fabricate ultrathin metal-organic framework (MOF) nanosheet arrays doped with two rare-earth elements, Y and Ce, and self-supported on nickel foam (NF) to enhance the HER and OER performance by constructing abundant active sites and bimetallic synergistic effects. The NiYCe-MOF/NF features an ultrathin nanosheet array structure and is uniformly and richly codoped by Y and Ce. When it was explored as both the anode and cathode electrocatalysts for overall water splitting, it achieved 10 mA cm

Direct alcohol fuel cells represent a promising green and sustainable route for chemical to electrical energy conversion; however, designing highly efficient electrocatalysts for the electro-oxidat...

Electrocatalytic CO2 reduction reaction is regarded as an intriguing route for producing renewable chemicals and fuels, but its development is limited by the lack of highly efficient and stable electrocatalysts. Herein, we propose the pipet-like bismuth (Bi) nanorods semifilled in nitrogen-doped carbon nanotubes (Bi-NRs@NCNTs) for highly selective electrocatalytic CO2 reduction. Benefited from the prominent capillary and confinement effects, the Bi-NRs@NCNTs act as nanoscale conveyors that can significantly facilitate the mass transport, adsorption,and concentration of reactants onto the active sites, realizing rapid reaction kinetics and low cathodic polarization. The spatial encapsulation and separation by the NCNT shells prevents the self-aggregation and surface oxidation of Bi-NRs, increasing the dispersity and stability of the electrocatalyst. As a result, the Bi-NRs@NCNTs exhibit high activity and durable catalytic stability for CO2-to-formate conversion over a wide potential range. The Faradaic efficiency for formate production reaches 90.9% at a moderate applied potential of -0.9 V vs reversible hydrogen electrode (RHE).

Solar-driven nitrogen fixation is a promising clean and mild approach for ammonia synthesis beyond the conventional energy-intensive Haber-Bosch process. However, it is still challenging to design highly active, stable, and low-cost photocatalysts for activating inert N2 molecules. Herein, we report the synthesis of anatase-phase black TiO2-xSy nanoplatelets enriched with abundant oxygen vacancies and sulfur anion dopants (VO-S-rich TiO2-xSy) by ion exchange method at gentle conditions. The VO-S-rich TiO2-xSy nanoplatelets display a narrowed bandgap of 1.18 eV and much stronger light absorption that extends to the near-infrared (NIR) region. The co-presence of oxygen vacancies and sulfur dopants facilitates the adsorption of N2 molecules, promoting the reaction rate of N2 photofixation. Theoretical calculations reveal the synergistic effect of oxygen vacancies and sulfur dopants on visible-NIR light adsorption and photoexcited carrier transfer/separation. The VO-S-rich TiO2-xSy exhibits improved ammonia yield rates of 114.1 μmol g-1 h-1 under full-spectrum irradiation and 86.2 μmol g-1 h-1 under visible-NIR irradiation, respectively. Notably, even under only NIR irradiation (800-1100 nm), the VO-S-rich TiO2-xSy can still deliver an ammonia yield rate of 14.1 μmol g-1 h-1. This study presents the great potential to regulate the activity of photocatalysts by rationally engineering the defect sites and dopant species for room-temperature N2 reduction.

Developing the efficient and stable anode catalysts of direct methanol fuel cell has been a pivotal requirement for its extensive commercial application. Herein, we design the Fe-doped CoP nanotube heterostructure as the co-catalyst of Pt-based catalyst via combining a facile hydrothermal with phosphorization process, subsequently, the traditional NaBH4 reduction method is utilized to deposit Pt nanoparticles. As anticipated, Fe species have been successfully doped into CoP to generate the Fe-doped CoP nanotube heterostructure, and the involved characterizations identify that Pt–C/Fe2–CoP catalyst exhibits admirable mass activity (1237 mA·mg−1Pt) towards methanol oxidation reaction, which is approximately 2.04 and 3.66 times as high as the Pt–C/CoP (607 mA·mg−1Pt) and Pt–C–H (338 mA·mg−1Pt). After stability test, the decline ratio of mass activity for Pt–C/Fe2–CoP (83.43%) is markedly preferable to Pt–C/CoP (94.92%) and Pt–C–H (98.67%) catalysts. The enhanced catalytic activity and durability can be imputed to the formation of uniform Pt nanoparticles and co-catalysis effect of Fe-doped CoP nanotube heterostructure since the introduction of hetero-metal cations is able to effectively accelerate the charge transfer rate and adjust the electronic structure of material. Therefore, the fabrication of nanotube heterostructure and introduction of hetero-metal may provide a new direction to the development of other high-efficiency electrocatalysts.

Developing high-performance nitrogen reduction reaction (NRR) electrocatalysts is an ongoing challenge. Herein, we report a pyrolysis-free synthetic method for introducing ordered quasi-phthalocyanine N-coordinated transition metal (Ti, Cu, or Co) centers into a conjugated two-dimensional (2D) covalent organic framework (COF) for enhanced NRR performance. Detailed experiments and characterizations revealed that the NRR activity of Ti-COF was clearly better than that of Cu-COF and Co-COF, because of the superior abilities of Ti metal centers in activating inert N

The construction of cost-effective and durable electrocatalysts for methanol oxidation reactions (MOR) is a major challenge for direct methanol fuel cells. Herein, we report a novel catalyst support with CoMoO4 in-situ coated on the Co,N-doped carbon polyhedrons (Co,N-DCP) by a hydrothermal method. Owing to the efficient electron transport, unique architectural structure and synergistic effect of carbon framework, bimetal oxides and Pt nanoparticles, the integrated Pt–CoMoO4@Co,N-DCP catalyst exhibits excellent MOR activity in alkaline electrolyte (a mass specific activity of 4450 mA mgpt−1 at 50 mV s−1 was achieved), which is nearly three times improvement when compared with the commercial Pt/C catalyst. Furthermore, the obtained Pt–CoMoO4@Co,N-DCP catalyst possesses remarkable electrochemical durability compared to commercial Pt/C. These results revealed that the Pt–CoMoO4@Co,N-DCP hybrid is a promising catalyst for MOR. The current work offers new perspectives in the designing of novel structure, highly active and stable catalysts materials in the application of DMFCs electrocatalysis.

Honeycomb-like nitrogen-doped carbon/polyaniline (HNC/PANI) composite is prepared by a facile two steps method. The honeycomb-like nitrogen-doped carbon skeleton, with uniform pore sizes and three-dimensionally ordered structure, is obtained via the sacrificial template method and polyaniline is served as the N and C source during this progress. The specific surface area is 1056 m2 g−1, which is much higher than that of the disordered nitrogen-doped carbon (named NDC) and pure PANI. The subsequent polyaniline nanofibers with different concentrations are in-situ polymerization on carbon skeleton. The as-prepared HNC/PANI shows excellent performance of supercapacitors is demonstrated by the electrochemical evaluation, which specific capacitance is as high as 686 F g−1 at 1 A g−1 along with the good rate performance and superior cyclic stability (87.8% after 5000 cycles at 10 A g−1, which is superior to the NDC/PANI and pure PANI electrode). Perhaps this work offers a novel approach to improve the specific capacitance and cycle stability of supercapacitors via the ordered honeycomb-like carbon framework.

The novel Cu-doped CeO2 (Ce1‐xCuxO2‐δ) nanotubes as a superior co-catalyst have been primarily fabricated by coupling reflux with thermolysis methods. Then scanning electron microscopy and transmission electron microscopy reveal that the length of nanotube ranges from 200 nm to 700 nm and its diameter is about 80 nm, and interestingly, these nanotubes can orderly build up into the unique 3D nanobundles. After depositing Pt nanoparticles onto the hybrid support consisted of Vulcan XC-72R and Ce1‐xCuxO2‐δ, a few PtCu alloys appear on the surface of Ce1‐xCuxO2‐δ nanotubes. Afterwards, correlative evaluations declare clearly that Pt/C-Ce0.8Cu0.2O2‐δ catalyst possesses better electrocatalytic performance and CO resistance, and its electrochemical specific surface area (ECSA) is as high as 142.9 m2·g‐1, which is one of the best outcomes reported up to now. The fortified catalytic performance of Pt/C-Ce0.8Cu0.2O2‐δ may be because the introduction of Cu atom improves the electric conductivity and oxygen vacancy of CeO2, moreover, the hollow structure of nanotubes is beneficial to enhance the charge transfer and ECSA. Therefore, this study not only confirms an extremely handy pathway to synthesize the particular structure, but also offers more possibilities for the development of efficient electrocatalyst in methanol oxidation.

Herein, the carbon spheres decorated by binary and ternary layered double hydroxide are successfully fabricated via a usual one-pot method. Subsequently, a typical microwave-assisted polyol process is employed for depositing Pt nanoparticles. The Pt nanoparticles are well-distributed and the average particle size is around 1.6 ± 0.2 nm. Meanwhile, electrochemical evaluations state clearly that the mass activity of Pt/C@NiRu layered double hydroxide and Pt/C@NiRuCe layered double hydroxide separately is 2032 mA·mg−1Pt and 2475 mA·mg−1Pt in alkaline solution. And unexpectedly, the obtained Pt/C@NiRu layered double hydroxide with mass activity of 686 mA·mg−1Pt and Pt/C@NiRuCe layered double hydroxide with mass activity of 725 mA·mg−1Pt possess better electrocatalytic performance and CO resistance than home-made Pt/C (273 mA·mg−1Pt) in acid medium. These results can be likely summarized that layered double hydroxide will provide tremendous OH species for facilitating the oxidation of poisonous intermediates and enhancing the interaction between metal Pt and support, additionally, cerium-doped also can efficaciously propel the charge transfer and catalytic activity. Thereby, the convenience-oriented approach of modified carbon by layered double hydroxide with abundant hydroxyl provides more possibility for the application of layered double hydroxide on electrocatalyst, and sheds novel light into the evolution of efficient catalyst in methanol electrooxidation.

In this study, hollow porous carbon sphere@cobalt phosphide/nitrogen-doped carbon (HPCS@CoP/NC) was firstly prepared via a precursor conversion method and low temperature phosphidation process. Subsequently, a HPCS@CoP/NC supported Pt catalyst (Pt–HPCS@CoP/NC) was fabricated through a microwave-assisted polyol strategy. The physical characterization results show that the obtained HPCS@CoP/NC support with mesopores has a high specific surface area (379.96 m2 g−1). Electrochemical studies reveal that the Pt–HPCS@CoP/NC catalyst exhibits a high mass activity of 688 mA mgPt−1 upon methanol electrooxidation, which is almost 1.7 times higher than that of commercial Pt–C (393 mA mgPt−1). Meanwhile, the Pt–HPCS@CoP/NC catalyst exhibits better CO tolerance and cycling stability in comparison with other catalysts in this work. These excellent catalytic properties can be attributed to the enhancement effect that CoP has on Pt-based catalysts, as well as the unique nanostructure. Thereby, this study demonstrates the attractive merits of the Pt–HPCS@CoP/NC catalyst for application in methanol electrooxidation.

Worm-like PtP nanocrystals supported on NiCo 2 P x /carbon black (NiCo 2 P x /C) composites were prepared by a combined hydrothermal, low temperature phosphidation and NaBH 4 reduction process. Noteworthily, the presence and content of phosphorus (P) play a critical role in constructing one-dimensional (1D) PtP nanostructures. Electrochemical tests demonstrate that the obtained PtP-NiCo 2 P x /C hybrid exhibits an extremely high mass activity of 1361 mA mg −1 Pt for methanol electrooxidation in acidic medium, which is 3.5- and 7.6-fold greater than those of commercial Pt/C (393 mA mg −1 Pt ) and home-made Pt/C catalyst (180 mA mg −1 Pt ), respectively. Meanwhile, the catalytic performence of PtP-NiCo 2 P x /C is also better than those of the PtP-CoP/C and PtP-Ni 2 P/C catalysts due to the synergistic effect of Co and Ni. Furthermore, PtP-NiCo 2 P x /C catalyst exhibited better durability and CO tolerance compared with other catalysts in this study. The enhanced catalytic performence of PtP-NiCo 2 P x /C hybrid can be attributed to the special 1D morphology of PtP nanocrystals, the strong interaction between catalytic species and support, as well as the existence of metal center (M δ+ , M = Ni or Co) and P δ− active sites for the dissociation of H 2 O molecules. The design of 1D PtP alloy nanostructures and co-catalytic effect of NiCo 2 P x provides a promising method to significantly improve methanol oxidation performence.

Electrocatalytic CO

Solar-driven nitrogen fixation is a promising clean and mild approach for ammonia synthesis beyond the conventional energy-intensive Haber-Bosch process. However, it is still challenging to design highly active, stable, and low-cost photocatalysts for activating inert N

As emerging 2D materials, arsenene and arsenic materials have attracted rising interest in the past few years. The diverse crystalline phases, exotic electrical characteristics, and widespread applications of 2D arsenene and arsenic bring them great research value and utilization potential. Herein, the recent progress of 2D arsenene and arsenic is reviewed in terms of fundamental properties, preparation, and applications. The fundamental properties of 2D arsenene and arsenic, including the crystal phases, environmental stability, and electrical structure, from theoretical to experimental reports are first summarized. Then, the experimental processes for preparing 2D arsenene and arsenic, along with their respective advantages and disadvantages, are introduced including epitaxial growth, mechanical exfoliation, and liquid-phase exfoliation. Moreover, applications of 2D arsenene and arsenic are discussed, suggesting a wide range of applications of 2D arsenene and arsenic in field-effect transistors, sensors, catalysts, biological applications, and so on. Finally, some perspectives about the challenges and opportunities of promising 2D arsenene and arsenic are provided. This review provides a helpful guidance and stimulates more focus on future explorations and developments of 2D arsenene and arsenic.

The construction of highly active Pt-based catalyst for methanol electrooxidation is still an ongoing challenge. Herein, irregular PtP nanocrystals with the length is around 7 nm supported on the Fe2O3@FeP/C composites consisting of Fe2O3@FeP core-shell nanocubes and carbon black particles are synthesized by an integrated hydrothermal, low temperature phosphidation and NaBH4 reduction process. TEM and EDS reveal that both the presence of phosphorus (P) and the mild Pt reduction method are play a critical role in constructing irregular PtP nanocrystals. Interestingly enough, the confinement effect of carbon particles on iron ions in the process of hydrothermal reaction leads to the generation of Fe-precursor nanocubes. Benefiting from the P can effectively modify the electronic state of the Pt surface, the strong interaction between special irregular PtP nanocrystals and the support surface as well as Fe2O3@FeP core-shell nanocubes for the enhanced activation and decomposition of H2O molecules, the as-prepared PtP-Fe2O3@FeP/C-8 h catalyst exhibits better anti-CO poisoning ability, stability and excellent catalytic activity for methanol oxidation. Specifically, the mass activity (831 mA mg−1Pt) of PtP-Fe2O3@FeP/C-8 h is 4.6- and 2.1-times greater than that of home-made Pt/C (Pt/C-H) (180 mA mg−1Pt) and commercial Pt/C (Pt/C-JM) (393 mA mg−1Pt) catalyst in acidic medium. At the same time, the mass activity of PtP-Fe2O3@FeP/C-8 h is as high as 3215 mA mg−1Pt, which is much higher than those of Pt/C-H (1298 mA mg−1Pt) and Pt/C-JM (1548 mA mg−1Pt) catalysts in alkaline medium. The present work provides a new entry points into the synthetic way for the irregular PtP nanocrystals and cheap co-catalytic species for methanol oxidation reaction (MOR).