Aiming at improving the thermoelectric (TE) performance of the GeTe monolayer by means of doping, we systematically investigate the TE properties of the doped GeTe monolayers. By testing most of the atoms in Groups IIA-VA, we found that Be, Mg, Sn, and Pb are possible dopants in view of their stability and electrical conductivity. It is shown that the doping atom types and the doping concentrations can make different influences on the electronic energy band structures, the phononic spectra, and the electronic (phononic) transmission spectra. Furthermore, the Seebeck coefficientS, the electrical conductanceG, the power factorS2G, and the electronic (phononic) thermal conductancesκe(ph)will be changed to varying extents. Finally, we find that the resulting figures of meritZTs are closely dependent on the doping atom types and the doping concentration. In comparison with the pristine GeTe monolayer, theZTpeaks of the doped one can be manipulated by the atomic doping. At appropriate doping concentrations for different doping atoms, theseZTpeaks can be improved. Our findings demonstrate the feasibility of using Be, Mg, Sn, and Pb as the dopants to enhance the TE performance of the GeTe monolayer.

Seawater electrolysis offers a sustainable green way for hydrogen production. However, it faces challenges owing to the lack of electrocatalysts with high activity and stability, along with effective inhibition of chlorine oxidation reaction. Herein, Ni3S2 nanosheets with rich dislocations (D-Ni3S2) are prepared as a bifunctional electrocatalyst for overall alkaline seawater electrolysis. The D-Ni3S2 nanosheets are in situ grown on a nickel foam by thermal treatment of nickel foam with thioacetamide in ammonia atmosphere. Various characterizations indicate that D-Ni3S2 nanosheets have rich dislocations, which create compressive strain within lattice and thus shorten Ni-S bonds. This effect optimizes the electronic states of Ni and S, leading to enhanced activity for overall water splitting. The D-Ni3S2-based electrolyzer therefore show a cell voltage of 1.638 V and 1.611 V at 10 mA/cm2 for alkaline fresh water and seawater electrolysis, respectively. Particularly, the Faraday efficiencies for seawater electrolysis is above 90%.

Aiming at exploring new thermoelectric (TE) materials of high performance, we theoretically calculate the TE transport properties including the Seebeck coefficient, electrical conductance, thermal conductance, power factor, and figure of merit ZT of the SnS monolayer. Different from the heavy-metal doping, the economical and environment-friendly Na doping is adopted to improve the ZT of the monolayer SnS. It is shown that the Na doping can increase the maximum ZT along the armchair and zigzag directions, respectively, and the highest ZT peak is moved to the proximity of chemical potential mu = 0 eV, which indicates that the corresponding TE device can work at a low bias voltage. As the temperature increases from 300 K to 800 K, the maximum ZT of the pristine SnS monolayer is increased from 0.89 to 2.26 (from 1.33 to 2.89) along the armchair (zigzag) direction, and the maximum ZT of the Na-doped one is increased from 1.24 to 2.45 (from 1.44 to 2.86) along the armchair (zigzag) direction. This implies that the Na-doped SnS monolayer can be utilized to design promising TE devices working in a broad temperature scope and at a lower bias voltage.

Aiming at finding wide-temperature-zone thermoelectric (TE) materials, five kinds of monolayer GeTe allotropes including the newly designed gamma-, delta-, and epsilon-GeTe monolayers and the usual alpha- and beta-GeTe ones are constructed. By using the density functional theory and the nonequilibrium Green's function method, all their electronic properties and TE transport properties are comparatively investigated. It is found that the room-temperature figure of merit ZT of the gamma-GeTe (epsilon-GeTe) along the armchair (zigzag) direction can amount to 4.5 (3.5), which is further increased to 7.15 (5.91) at 700 K. These ZT values are much higher than the other IV-VI compounds usually with ZT < 3, indicating that the armchair gamma-GeTe and the zigzag epsilon-GeTe we designed here can be used as superior wide-temperature-zone and high-performance TE materials in the temperature range from 300 K to 700 K. Moreover, with the increase of temperature, the ZT peaks will become wider in width and move towards the position of zero chemical potential, which will make the GeTe-based TE devices work at low bias voltages more efficiently. This work should be an important reference on the way to the stage of, ZT >= 4 which will motivate more explorations into the high-performance TE materials working in a wider temperature scope.

Proton exchange membrane (PEM) water electrolyzers are one type of the most promising technologies for efficient, nonpolluting and sustainable production of high-purity hydrogen. The anode catalysts account for a very large fraction of cost in PEM water electrolyzer and also determine the lifetime of the electrolyzer. To date, Ir- and Ru-based materials are types of promising catalysts for the acidic oxygen evolution reaction (OER), but they still face challenges of high cost or low stability. Hence, exploring low Ir and stable Ru-based electrocatalysts for acidic OER attracts extensive research interest in recent years. Owing to these great research efforts, significant developments have been achieved in this field. In this review, the developments in the field of Ir- and Ru-based electrocatalysts for acidic OER are comprehensively described. The possible OER mechanisms are first presented, followed by the introduction of the criteria for evaluation of the OER electrocatalysts. The development of Ir- and Ru-based OER electrocatalysts are then elucidated according to the strategies utilized to tune the catalytic performances. Lastly, possible future research in this burgeoning field is discussed.

Background: As an effective approach to the control and utilization of CO2, the direct synthesis of dimethyl carbonate (DMC) from CO2 and methanol has received widespread attention, while efficient catalysis is extremely crucial for this process. Methods: CeO2 based nano-flowers (M-CeO2-NF) doped with rare earth metals (M=La, Pr, or Nd) was prepared by hydrothermally assisted coprecipitation method. The roles of rare earth metal doping on properties and catalytic performance were investigated. The interactions between the doped metals and CeO2 and the mechanism of the catalytic process are further revealed. Significant Findings: Rare earth metal doping (1 % molar content) can adjust the specific surface area, pore structure, and surface oxygen vacancy properties without changing the nanoflower structure of the catalysts, thereby influencing their catalytic performance. The Nd-CeO2 NF exhibited the highest content of oxygen vacancy and presented the superior DMC productivity of 9.58 mmol & sdot;g-1 cat., improved by 32 % compared with pure CeO2-NF. Additionally, the Nd-CeO2-NF catalyst also show considerable reusability. A possible reaction pathway was proposed based on the in-situ infrared characterization and the experimental results of the catalytic reaction.

To identify α-synuclein aggregation in synucleinopathies is still challenging, due to the lack of specific probes for α-synuclein aggregates with efficient brain uptake. In this work, compact molecules based on coumarin scaffold were synthesized and evaluated for detection and bioimaging of α-synuclein aggregates in the brain. Among the developed compounds, azocoumarin 5 containing push-pull electronic architecture featured selective fluorescence enhancement towards α-synuclein aggregates in comparison to other β-sheet protein species (β-amyloid, tau). In addition, azocoumarin [18F]Cou-NNF was succesfully developed, and demonstrated its potential as radiotracer for imaging brain α-synuclein aggregates, owing to its favorable affinity for α-synuclein aggregates accompanied with efficient brain uptake and little defluorination in vivo. Overall, compact azocoumarin provides an effective lead structure for developing α-synuclein probes, and N=N bond shows promise in enhancing selective affinity for α-synuclein aggregates.

The relatively high potential barrier prevents the bistable energy harvester from achieving interwell oscillations. A dual-coupling beams energy harvester (DEH) has been previously proposed to accomplish large-amplitude interwell motion for low-level excitations. The DEH consists of a linear resonant harvester (LSH) and a bistable energy harvester (BEH), which are elastically coupled with a linear spring. However, the sensitivity of its dynamic characteristics to the system parameters is not investigated. In addition, only the dynamic behavior of the DEH with symmetric potential wells is investigated, while the dynamic characteristics of the DEH with asymmetric potential wells is not explored. Hence, this paper provides a theoretical analysis of the impact of external resistance, the external excitation, the internal system parameters, and the asymmetric potential wells on the dynamic responses of the DEH by using the harmonic balance method. The results reveal that the introduction of the spring and LSH will lead to a reduction in the excitation acceleration threshold for achieving large-amplitude interwell motion, as well as an increase in the high-energy orbit output voltage and the operation bandwidth for Beam 1 of the DEH. The high-energy orbit output voltage in asymmetric potential wells is mainly determined by the shallow potential well depth. On the other hand, the low-energy orbit output voltage of Beam 1 of the DEH with asymmetric potential wells is influenced by the depth difference between the two potential wells. However, with the increased stiffness of the coupling spring, the influence of the depth difference between the two potential wells on the low-energy orbit output voltage will be reduced.

With the penetration of automobiles, spent automobile catalysts are the major secondary source of Platinum group metals. Spent automotive catalyst has higher quantities of platinum group metals than natural ores. Recovering platinum group metals from spent automotive catalysts has the potential to yield significant economic and environmental benefits. Conventional recycling techniques necessitate the use of several chemical reagents or the deployment of high-tech equipment and significant energy consumption, which inevitably results in the generation of toxic and harmful substances. However, biorecovery processes are regarded as viable options for Platinum group metals recovery. The substantial ability of microorganisms to bioreduce metal ions may obtain metal nanoparticles of varying morphologies and sizes through the action of various enzymes (reductase, hydrogenase) and proteins. This review summarizes the current process of biosynthesis of Platinum group metal nanoparticles, as well as potential synthesis mechanisms. Meanwhile, the specific applications of microbial sourced nanoparticles in medicine, catalytic environmental pollutants, and biosensors are discussed, and the future development of microbial nanomaterials synthesis has been further prospected.

Recent studies have extensively explored the phonon heat transport properties of bulk hexagonal boron nitride (h-BN); however, the influence of stacking order on its thermal conductivity (x) has received rare attention. In this work, we employ first-principles calculations to predict the thermal conductivity of h-BN with wurtize (w), AB, and ABC stacking. Our calculations show that w-BN possesses the highest thermal conductivity, with in-plane and out-of-plane values of 611 W/mK and 521 W/mK at room temperature (RT), respectively. In contrast, AB and ABC stacking exhibit comparable thermal conductivities, with RT in-plane (out-of-plane) values of 338 (5.8) and 357 (7.2) W/mK, respectively. Notably, four-phonon scattering is found to reduce the x of ABC and AB stacking by 9% and 13% at RT, while exerting non-negligible suppression on the x of w-BN only at high temperature. Through detailed mode-level analysis, we uncover that the lower thermal conductivity of AB and ABC stacking, compared to w-BN, stems from their stronger phonon anharmonicity, driven by weak interlayer van der Waals interactions. Furthermore, the calculated modal x reveals that the stacking sequence has opposite effects on the out-of-plane flexural acoustic phonons and other modes, and their competing effect noticeably weakens the difference in x between AB and ABC stacking phases. This work provides a fundamental understanding of the phonon thermal transport properties of bulk h-BN with different stacking orders and elucidates the roles of stacking order and higher-order anharmonicity in determining the thermal conductivity of van der Waals layered materials.

Since the basic thermoelectric (TE) units must be integrated on substrates to form large-scale devices, it would be more practical to study the TE properties of the TE devices with substrates. Based on the first-principles calculation and nonequilibrium Green’s function method, we comparatively investigate the TE properties of the GeTe monolayer with its leads deposited on Au, Ni, and Co substrates, which are called GeTe-X (X = Au, Ni, and Co). It is shown that in comparison with the pristine GeTe monolayer, the figures of merit ZTs of the GeTe-X are seriously changed with one ZT peak appearing near zero chemical potential. The GeTe-Au and GeTe-Ni are of higher TE performance near zero chemical potential than the GeTe-Co, indicating one can choose Au or Ni as the substrate. Moreover, we show that the TE properties of the GeTe-X are sensitively dependent on the substrate layer number, the central scattering length, and the temperature, which necessitates the synergistic optimization of the related parameters to obtain the best TE performance. This work should be an important reference for designing practical GeTe-based TE devices.

FeNi bimetallic oxides are considered as a potential catalyst candidate material for efficient oxygen evolution. However, low conductivity, rapid structural collapse, and metal ion release always lead to electrochemical performance and poor stability, which become major challenges in the electrochemical process. Herein, we synthesized self-standing 3D rose-like bimetallic oxides modified nitrogen-doped graphite aerogels (FeNiOx@N/ GA) by the facile layer-by-layer self-assembled method. The unique 2D/3D structure composed of 2D ultrathin graphene nanosheets decorated 3D microflowers can provide a large active area and a rapid charge transfer rate. Moreover, both oxidation and nitrogen doping can improve the reaction kinetics of the material, thereby exhibiting higher catalytic activity. FeNiOX@N/GA X @N/GA exhibits excellent oxygen evolution reaction (OER) performance (eta 10=291 10 =291 mV) and low Tafel slope (39 mV dec-1)- 1 ) in the 1 M KOH. This work can be expected to provide a novel and valid method for rational design and manufacture of advanced bimetallic oxides-based positive electrode toward efficient OER. Meanwhile, FeNiOx@N/GA is loaded on nickel foam and displays good electrochemical properties as an air-cathode in Zn-Air battery, demonstrating outstanding practicability.

Rheumatoid arthritis (RA) is a chronic autoimmune disease. Its pathological features include synovial inflammation, bone erosion, and joint structural damage. Our previous studies have shown that interleukin (IL)-35 is involved in the pathogenesis of bone loss in RA patients. In this study, we are further evaluating the efficacy of IL-35 on collagen-induced arthritis (CIA) in the mouse model. Male DBA/1J mice (n = 10) were initially immunized, 2 μg/mouse IL-35 was injected intraperitoneally every week for 3 weeks after the establishment of the CIA model. Clinical arthritis, histopathological analysis, and three-dimensional micro‑computed tomography (3D micro‑CT) were determined after the mice were anesthetized on the 42th day. In vitro, RANKL/M-CSF induced mouse preosteoclasts (RAW264.7 cells line) was subjected to antiarthritis mechanism study in the presence of IL-35. The results of clinical arthritis, histopathological analysis, and 3D micro‑CT, the expression of RANK/RANKL/OPG axis, inflammatory cytokines, and osteoclastogenesis-related makers demonstrated decreasing severity of synovitis and bone destruction in the ankle joints after IL-35 treatment. Furthermore, IL-35 attenuated inflammatory cytokine production and the expression of osteoclastogenesis-related makers in a mouse preosteoclasts cell line RAW264.7. The osteoclastogenesis-related makers were significantly reduced in IL-35 treated RAW264.7 cells line after blockage with the JAK/STAT1 signaling pathway. These results demonstrated that IL-35 protein could inhibits osteoclastogenesis and attenuates CIA in mice. We concluded that IL-35 can exhibit anti-osteoclastogenesis effects by reducing the expression of inflammatory cytokines and osteoclastogenesis-related makers, thus alleviating bone destruction in the ankle joint and could be a potential therapeutic target for RA.

Motivated by the excellent thermoelectric (TE) performance of bulk SnSe, extensive attention has been drawn to the TE properties of the monolayer SnSe. To uncover the fundamental mechanism of manipulating the TE performance of the SnSe monolayer, we perform a systematic study on the TE properties of five monolayer SnSe allotropes such as α -, β -, γ -, δ -, and ε -SnSe based on the density functional theory and the non-equilibrium Green’s functions. By comparing the TE properties of the Na-doped SnSe allotropes with the undoped ones, the influences of the Na doping and the temperature on the TE properties are deeply investigated. It is shown that the figure of merit ZT will increase as the temperature increases, which is the same for almost all the Na-doped and undoped cases. The Na doping can enhance or suppress the ZT in different SnSe allotropes at different temperatures, implying the presence of the anomalous suppression of the ZT . The Na doping induced ZT suppression may be caused basically by the sharp decrease of the power factor and the weak decrease of the electronic thermal conductance, rather than by the decrease of the phononic thermal conductance. We hope this work will be able to enrich the understanding of the manipulation of TE properties by means of dimensions, structurization, doping, and temperature.

A theoretical investigation into the thermoelectric (TE) properties of the undoped and Tl-doped SiP3 monolayers has been performed based on the first-principles calculations. The Seebeck coefficient peak and valley, the electronic conductance valley, and the thermal conductance valley of the SiP3 can be moved to the positions close to the Fermi level by the Tl doping. In addition, the two peaks of figures of merit ZTs are also shifted with enhanced ZT peak values. Furthermore, different dependences of ZTs on temperature are observed for the undoped and Tl-doped SiP3 monolayers. At low temperatures both the undoped and Tl-doped SiP3 can show high ZTs, while at high temperatures the Tl-doped SiP3 shows much higher ZT than the undoped one especially along the zigzag direction. This work demonstrates that the SiP3 and Tl-doped SiP3 monolayers can be used as high-performance TE materials.

Solar photocatalytic hydrogen production is attracting great attention for addressing the environmental and energy challenges, while the low solar-to-hydrogen (STH) efficiency of photocatalysts hinders its industrial implementation. To enhance the STH efficiency, the construction of single-atom photocatalyst and direct Zscheme heterojunctions (HJs) is deemed as promising strategies. This work has thoroughly studied the photo- catalytic properties of WSe2/ZrS2, GaTe/ZrS2 van der Waals HJs, as well as these HJs anchored by single atoms (Pt@WSe2/ZrS2, Pt@GaTe/ZrS2) using the first-principles calculations. The results indicate that appropriate bandgaps, band edge positions and internal electric field effectively accelerate photogenerated carrier migration via direct Z-scheme path in WSe2/ZrS2 and GaTe/ZrS2 HJs. After anchoring Pt atoms onto the reducing agent layer of these HJs, the hydrogen evolution performance of both Pt@WSe2/ZrS2 and Pt@GaTe/ZrS2 systems are significantly enhanced, enabling spontaneous redox reactions. Furthermore, these HJs exhibit excellent light absorption capacity, with their optical absorption spectra even expanding into the near-infrared range. Especially, the STH efficiency of Pt@GaTe/ZrS2 HJ reaches 12.94%, surpassing the threshold necessary for future industrial applications. Therefore, this study presents a novel strategy for precisely modulating photocatalytic performance and predicts that Pt@WSe2/ZrS2 and Pt@GaTe/ZrS2 HJs are promising direct Z-scheme systems for overall water splitting.

The obstacles in further improving the heat-transport performance of the graphene-based films root in the random stacking configuration of the graphene flakes and their agglomeration in solvents. In order to overcome these obstacles, we design one kind of quasi-bilayer graphene device composed of one upper narrow nanoribbon and one lower wide nanoribbon with absorbed perfluorophenylazide (PFPA) molecules. By investigating the thermal conductivity (TC) of the quasi-bilayer graphene without absorbed PFPA molecules, we find the TC will increase as the length and width increase, while the TC will decrease with the increase of the layer number. This indicates that a quasi-bilayer graphene flake of a large area and a small layer number will be beneficial to increasing its TC. Furthermore, in the presence of the PFPA molecules, the TC of the quasi-bilayer graphene, albeit suppressed by the PFPA molecules, is found to decrease slowly with the increase of the PFPA molecule number. This demonstrates a feasible way to fabricate the high-quality graphene-based films based on the technology of absorbing PFPA molecules. This research should be an important reference for designing the graphene-based thermal functional devices.

Investigation of highly effective and affordable metal-based electrocatalysts is crucial for water splitting that yields pure hydrogen. Herein, using one-step room-temperature electrodeposition, we successfully created a binary metal nickel-iron sulfide bifunctional electrocatalyst having plenty of active sites and a significant specific surface area on nickel foam (NF). Additionally, the synergistic interaction of the two metal components, iron and nickel, facilitates the electron transfer process and increases the materials' electrocatalytic performance. To obtain 10 mA cm-2, the catalyst only requires 75 mV for HER and 210 mV for OER in 1.0 M KOH. The two-electrode electrolyzer only needs a modest driving voltage (1.46 V@10 mA cm-2). The research presented here offers fresh understandings into the water splitting of nickel-iron-based sulfides as well as a reasonable direction for the development of bifunctional electrocatalysts.(c) 2023 Hydrogen Energy Publications LLC. Published by Elsevier Ltd. All rights reserved.

Different from the extensive experimental investigations into the thermoelectric (TE) properties of the bulk IV–VI compounds, less attention has been paid to the TE properties of the monolayer IV–VI compounds. Here, we consider the TE transport properties including the Seebeck coefficient, electronic conductance, thermal conductance, power factor, and figure of merit ZT of the undoped and Bi-doped GeS monolayers. Our results show that for both the undoped and Bi-doped monolayers the anisotropy is widely observed in all their TE properties, and the maximum ZT at a certain temperature along the armchair direction is much greater than that along the zigzag direction. Moreover, Bi doping can lead to an increase of the maximum ZT, and there are more ZT peaks appearing near the zero chemical potential. This indicates that the Bi-doped GeS monolayer can work as a TE material at a lower bias voltage, and especially along the armchair direction it can work at zero bias voltage, which obviously strengthens the reliability of the TE devices. As the temperature increases, the maximum ZT will be uniformally increased along the armchair and zigzag directions for both the undoped and Bi-doped GeS monolayers. In the temperature scope from 300 to 800 K, the maximum ZT along the armchair direction of the Bi-doped GeS monolayer will increase from 3.39 to 4.85, which indicates that this Bi-doped GeS monolayer is a promising TE material in a wide-temperature zone. As an application, we have designed the GeS-based TE couples and found that their efficiencies can be greater than 27% at large temperature differences. This research should be an important guidance for designing a low-voltage, wide-temperature-scope, and high-stability TE device.

Based on first-principles density functional theory and nonequilibrium Green's function, we study the electronic band structures, the electronic transport properties, and the optical absorption of bilayer blue phosphorene nanoribbons (BPNRs). Both bilayer armchair BPNRs (a-BPNRs) and zigzag BPNRs (z-BPNRs) behave as semiconductors in the narrow nanoribbon case and metals in the wide nanoribbon case, sharply different from their monolayer counterparts where the monolayer a-BPNRs (z-BPNRs) are always semiconducting (metallic). This indicates that interlayer couplings or the increasing layer number may induce the switching of the conductivity of the monolayer BPNRs, which is absent in graphene and phosphorene nanoribbons. Furthermore, we explore the edge states of the energy bands near Fermi energy, and find that there are almost no pure edge-state band branches in the bilayer BPNRs, which can be attributed to the interlayer couplings between the edge-states in one layer and the bulk-states in the other. Consequently, the resulting complex band structures cannot be directly analyzed any more in the framework of the two-body coupling picture just according to the simple band structures of the monolayer BPNRs. Finally, we present the current-voltage characteristics and the optical absorption of the bilayer a-BPNRs and z-BPNRs. The influences of the nanoribbon width and the interlayer couplings on the current and the anisotropic optical absorption can be understood based on the complex energy band structures. This research should be an important reference of extending the field of BPNRs from the monolayer to the bilayer case, and deepen the understanding of the difference between the monolayer and bilayer nanoribbons in different materials.