Thermoelectric materials hold promises for direct conversion of heat into electricity, making them viable power sources for electronic devices. However, their practical applications in diverse outdoor environment are ...
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Thermoelectric materials hold promises for direct conversion of heat into electricity, making them viable power sources for electronic devices. However, their practical applications in diverse outdoor environment are hindered by limited and discontinuous electricity output. In this study, we propose an all-day solar power generator to achieve highly efficient and continuous electricity generation by harnessing the synergistic effects of photoelectric-thermoelectric conversion and latent thermal energy storage. The all-day solar power generator exhibits an average open-circuit voltage of 6.8 mV during daylight and a remaining 0.9 mV during nighttime. Importantly, the all-day solar power generator achieves dependable outdoor power supply for communication transmission in diverse environmental scenarios. Our research opens a new way for highly efficient and sustainable power generation.
G115 martensitic steel is anticipated to be one of the preferred candidate materials in ultra-super critical(USC)power plants with steam temperatures above 650℃.Microstructure evolutions and mechanical properties of ...
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G115 martensitic steel is anticipated to be one of the preferred candidate materials in ultra-super critical(USC)power plants with steam temperatures above 650℃.Microstructure evolutions and mechanical properties of G115 martensitic steel after applying various heat treatment processes were *** results demonstrate that the main precipitate in G115 martensitic steel after applying various heat treatment processes is M23C6 phase with Cr *** time required for M23C6 phase precipitation decreases with increasing secondary normalizing temperature and the extension in holding time according to its precipitation-temperature-time(PTT)*** fraction of M23C6 phase increases with increasing secondary normalizing temperature and holding time,which strengthens the inhibitory effect of precipitates on dislocations recovery and laths ***,G115 martensitic steel can obtain the best mechanical properties after applying the highest secondary normalizing temperature and the longest holding *** the current work,the excellent strength of G115 martensitic steel mainly derives from precipitates strengthening and laths strengthening.
Retaining satisfactory electrocatalytic performance under high current density plays a crucial role in industrial water splitting but is still limited to the enormous energy loss because of insufficient exposure of ac...
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Retaining satisfactory electrocatalytic performance under high current density plays a crucial role in industrial water splitting but is still limited to the enormous energy loss because of insufficient exposure of active sites caused by the blocked mass/charge transportation at this ***,we present a freestanding lamellar nanoporous Ni-Co-Mn alloy electrode(Lnp-NCM)designed by a refined variant of the“dealloying-coarsening-dealloying”protocol for highly efficient bifunctional electrocatalyst,where large porous channels distribute on the surface and small porous channels at the *** its 3D lamellar architecture regulating,the electrocatalytic properties of the electrodes with different distances between lamellas are compared,and faster energy conversion kinetics is achieved with efficient bubble transport channels and abundant electroactive *** that the optimized sample(Lnp-NCM4)is expected to be a potential bifunctional electrocatalyst with low overpotentials of 258 and 439 mV at high current densities of 1000 and 900 mA·cm^(-2)for hydrogen and oxygen evolution reactions(HER and OER),*** overall water splitting in a two-electrode cell with Lnp-NCM4 as cathode and anode,it only needs an ultralow cell voltage of 1.75 V to produce 100 mA·cm^(-2)with remarkable long-term stability over 50 *** study on lamellar nanoporous electrode design approaches industrial water splitting requirements and paves a way for developing other catalytic systems.
The stacking structure of Nb_(2)CSe_(2),a newly synthesized layered metal carbo-selenide,was elucidated by scanning transmission electron ***,CSe2 features Se-Nb-C-Nb-Se quintuple atomic *** layers are stacked in Bern...
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The stacking structure of Nb_(2)CSe_(2),a newly synthesized layered metal carbo-selenide,was elucidated by scanning transmission electron ***,CSe2 features Se-Nb-C-Nb-Se quintuple atomic *** layers are stacked in Bernal *** this mode,Nb,CSe2 crystallizes in a trigonal symmetry(space group P3m1,No.164),with lattice parameters of a=3.33 A and c=18.20 *** structure calculations indicate that the metal carbo-selenide has Fermi energy crossing the bands where it touches to give a zero gap,indicating that it is an electronic *** evidenced experimentally,the electrical conductivity is as high as 6.6×10^(5) S·m^(-1),outperforming the counterparts in the MXene *** to the layered structure,the bonding in Nb_(2)CSe_(2) with an ionic formula of(Nb^(1.48+)),(C^(1.74-))(Se^(0.61-))_(2) is highly anisotropic,with metallic-covalent-ionic bonding in intralayers and weak bonding between *** layered nature is further evidenced by elastic properties,interlayer energy,and friction coefficient *** characteristics indicate that Nb_(2)CSe_(2) is an analog of molybdenum disulfide(MoS_(2)),which is a typical binary van der Waals(vdW)***,vibrational properties are reported,which may offer an optical identification standardfor new ternary vdW solids in spectroscopic studies,including Raman scatteringand infrared absorption.
High intraocular pressure(IOP) is one of the high-risk pathogenic factors of glaucoma. Existing methods of IOP measurement are based on the direct interaction with the cornea. Commercial ophthalmic tonometers based on...
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High intraocular pressure(IOP) is one of the high-risk pathogenic factors of glaucoma. Existing methods of IOP measurement are based on the direct interaction with the cornea. Commercial ophthalmic tonometers based on snapshot measurements are expensive, bulky, and their operation requires trained *** contact lenses are easy to use, but they may block vision and cause infection. Here, we report a sensory system for IOP assessment that uses a soft indentor with two asymmetrically deployed iontronic flexible pressure sensors to interact with the eyelid-eyeball in an eye-closed situation. Inspired by human fingertip assessment of softness, the sensory system extracts displacement-pressure information for soft evaluation, achieving high accuracy IOP monitoring(>96%). We further design and custom-make a portable and wearable ophthalmic tonometer based on the sensory system and demonstrate its high efficacy in IOP screening. This sensory system paves a way towards cost-effective, robust, and reliable IOP monitoring.
For the traditional peak-aged (PA) AA2024 alloy, the formation of large S-phase precipitates within the grains, wide precipitate-free zones (PFZs) near the grain boundaries (GBs), and continuous distribution of grain ...
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For the traditional peak-aged (PA) AA2024 alloy, the formation of large S-phase precipitates within the grains, wide precipitate-free zones (PFZs) near the grain boundaries (GBs), and continuous distribution of grain boundary precipitates (GBPs) can be observed. As a result, the PA alloy exhibits relatively high strength but poor corrosion resistance. However, with the application of cyclic plasticity treatment, high-density 1–2 nm clusters form within the matrix, and no PFZs form near GBs. In this study, this treatment yields the optimal balance between strength–elongation characteristics and corrosion resistance. By combining cyclic plasticity and ageing heat treatment with different heating rates, the nanoscale clusters play a crucial role as heterogeneous nucleation sites, resulting in the formation of finer and higher number density of S precipitates within the matrix. Additionally, the presence of these clusters reduces the formation of GBPs and minimizes the width of PFZs. Consequently, compared to the traditional PA sample, this approach achieves a significantly higher yield strength (increased by 46 %) and ultimate tensile strength (increased by 18 %), along with superior corrosion resistance. Although the influence of ageing heat treatment with different rates on mechanical properties is not significant, it notably affects the formation of GBPs and corrosion resistance. Specifically, a slower heating rate leads to an increase in the spacing between adjacent GBPs, resulting in improved corrosion resistance. In summary, cyclic strengthening, as a novel method for alloy strengthening, when combined with ageing heat treatment, modulates the distribution of S precipitates within the matrix and GBs. This optimization maximizes the effects of precipitation strengthening and breaks the inverse relationship between strength and corrosion resistance.
Carbyne, an elusive sp-hybridized linear carbon allotrope, has fascinated chemists and physicists for decades. Due to its high chemical reactivity and extreme instability, carbyne was much less explored in contrast to...
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Carbyne, an elusive sp-hybridized linear carbon allotrope, has fascinated chemists and physicists for decades. Due to its high chemical reactivity and extreme instability, carbyne was much less explored in contrast to the sp2-hybridized carbon allotropes such as graphene. Herein, we report the on-surface synthesis of polyynic carbon chains by demetallization of organometallic polyynes on the Au（111） surface;the longest one observed consists of ～60 alkyne units（120 carbon atoms）. The polyynic structure of carbon chains with alternating triple and single bonds was unambiguously revealed by bond-resolved atomic force microscopy. Moreover, an atomically precise polyyne, C14, was successfully produced via tip-induced dehalogenation and ring-opening of the decachloroanthracene molecule(C14Cl10) on a bilayer NaCl/Au（111） surface at 4.7 K, and a band gap of 5.8 eV was measured by scanning tunnelling spectroscopy,in a good agreement with the theoretical HOMO–LUMO gap（5.48 eV）.
Electroreduction of CO2for formic acid production has been regarded as an efficient option for ***, under high current, achieving high selectivity for formic acid is challenging, which cannot meet industrial demands. ...
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Electroreduction of CO2for formic acid production has been regarded as an efficient option for ***, under high current, achieving high selectivity for formic acid is challenging, which cannot meet industrial demands. Herein, we reported a type of Bi/In（OH）3（BIO） heterojunction reconstructed from Bi2S3/In（OH）3during electrochemical process, in which In（OH）3was applied to modulate the electronic structure of *** strategy efficiently enhanced the *OCHO intermediates adsorption and lead to a decent selectivity towards formic acid under high current density. BIO displays faraday efficiency of formic acid beyond 95 % across a wide range current density of 200–400 m A cm-2, where the highest value reached 97.7 % at 400 m A cm-2. This work clarified the mechanism of CO2electroreduction to HCOOH on heterojunction, guiding the design of advanced catalysts.
Potassium-ion batteries(PIBs)are considered as a promising energy storage system owing to its abundant potassium *** an important part of the battery composition,anode materials play a vital role in the future develop...
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Potassium-ion batteries(PIBs)are considered as a promising energy storage system owing to its abundant potassium *** an important part of the battery composition,anode materials play a vital role in the future development of ***-based anode materials demonstrate great potential for storing potassium ions(K^(+))due to their layered structure,high theoretical capacity based on the alloying reaction mechanism,and safe operating ***,the large radius of K^(+)inevitably induces severe volume expansion in depotassiation/potassiation,and the sluggish kinetics of K^(+)insertion/extraction limits its further ***,we summarize the strategies used to improve the potassium storage properties of various types of materials and introduce recent advances in the design and fabrication of favorable structural features of bismuth-based ***,this review analyzes the structure,working mechanism and advantages and disadvantages of various types of materials for potassium ***,based on this,the manuscript focuses on summarizing modification strategies including structural and morphological design,compositing with other materials,and electrolyte optimization,and elucidating the advantages of various modifications in enhancing the potassium storage ***,we outline the current challenges of bismuth-based materials in PIBs and put forward some prospects to be verified.
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