Seawater electrolysis is a highly promising method to produce high energy density hydrogen,especially in dry areas that have scarce freshwater ***,application of seawater electrolysis is confronted by two major proble...
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Seawater electrolysis is a highly promising method to produce high energy density hydrogen,especially in dry areas that have scarce freshwater ***,application of seawater electrolysis is confronted by two major problems associated with catalysts employed for the anodic oxygen evolution reaction(OER) including the competitive hypochlorite evolution reaction(HCER) and strong chloridion(Cl-) triggered *** studies aimed at overcoming these problems,a facile method has been developed to synthesize a homologous CoS2heterojunction as an OER *** to a difference in work functions at the interface and increased electron density,this material has directed electron transfer and strong chloridion repulsion properties,*** have shown that CoS2achieves low overpotentials of 289 and 322 mV at 10 mA cm-2current density in respective alkaline(1 M KOH) and alkaline simulated seawater ***,the outstanding stability of CoS2is reflected in a negligible decline in activity during promotion of the OER for 100 *** of density functional theory calculations reveal that the homologous CoS2heterojunction promotes directed electron transport for optimizing adsorption/desorption of reactive species and heightens the Cl-adsorption energy for strongly repulsing Cl-,phenomena that enhance OER performance in alkaline simulated seawater.
Porous ceramics are lightweight materials with diverse pore structures and are widely applied in areas such as thermal insulation, sound absorption, filtration, catalysis, and energy storage. However, excessive shrink...
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Porous ceramics are lightweight materials with diverse pore structures and are widely applied in areas such as thermal insulation, sound absorption, filtration, catalysis, and energy storage. However, excessive shrinkage during the sintering process of porous ceramics leads to cracking and deterioration, posing significant challenges for achieving complex shapes. Despite its importance, the field of low sintering shrinkage porous ceramics has not received sufficient attention. This review systematically discusses the principles and progress in the development of low sintering shrinkage porous ceramics. First, we introduce the characteristics of various preparation methods, including partial sintering, particle-stabilized foaming, gel-casting, foam-gelcasting, and additive manufacturing (AM). We then explain three primary principles of low sintering shrinkage from the perspectives of the volume effect and mass transfer processes. This review focuses on the properties and applications of typical low sintering shrinkage ceramics such as mullite and alumina, particularly their mechanical properties and thermal conductivity as thermal insulation and ceramic cores. Finally, we summarize the current state and present future perspectives on low sintering shrinkage porous ceramics.
Due to its low cost and natural abundance of sodium,Na-ion batteries(NIBs)are promising candidates for large-scale energy storage *** development of ultralow voltage anode materials is of great significance in improvi...
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Due to its low cost and natural abundance of sodium,Na-ion batteries(NIBs)are promising candidates for large-scale energy storage *** development of ultralow voltage anode materials is of great significance in improving the energy density of ***-voltage anode materials,however,are severely lacking in *** all the reported insertion oxides anodes,the Na_(2)Ti_(3)O_(7) has the lowest operating voltage(an average potential of 0.3 V ***^(+)/Na)and is less likely to deposit sodium,which has excellent potential for achieving NIBs with high energy densities and high *** significant progress has been made,achieving Na_(2)Ti_(3)O_(7) electrodes with excellent performance remains a severe *** paper systematically summarizes and discusses the physicochemical properties and synthesis methods of Na_(2)Ti_(3)O_(7).Then,the sodium storage mechanisms,key issues and challenges,and the optimization strategies for the electrochemical performance of Na_(2)Ti_(3)O_(7) are classified and further ***,remaining challenges and future research directions on the Na_(2)Ti_(3)O_(7) anode are *** review offers insights into the design of high-energy and high-safety NIBs.
A series of spinel-type Mg_(0.25-x)Al_(2.57)O_(3.79)N_(0.21):xMn^(2+)(MgAlON:xMn^(2+))phosphors were synthesized by the solid-state reaction *** transparent ceramic phosphors were fabricated by pressureless sintering ...
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A series of spinel-type Mg_(0.25-x)Al_(2.57)O_(3.79)N_(0.21):xMn^(2+)(MgAlON:xMn^(2+))phosphors were synthesized by the solid-state reaction *** transparent ceramic phosphors were fabricated by pressureless sintering followed by hot-isostatic pressing(HIP).The crystal structure,luminescence and mechanical properties of the samples were systematically *** transparent ceramic phosphors with tetrahedrally coordinated Mn^(2+)show strong green emission centered around 515 nm under blue light *** the Mn^(2+)concentration increases,the crystal lattice expands slightly,resulting in a variation of crystal field and a slight red-shift of green emission *** weak absorption peaks in the transmittance spectra originate from the spin-forbidden ^(4)T_(1)(^(4)G)→^(6)A_(1) transition of Mn^(2+).The decay time was found to decrease from 5.66 to 5.16 ms with the Mn^(2+)*** present study contributes to the systematic understanding of crystal structure and properties of MgAlON:xMn^(2+)green-emitting transparent ceramic phosphor which has a potential application in high-power light-emitting diodes.
The construction of donor-acceptor(D-A)molecular structure is an attractive strategy to enhance the photocatalytic performance of polymeric ***,dibenzothiophene(DBT)-4-carbaldehyde as the precursor is introduced into ...
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The construction of donor-acceptor(D-A)molecular structure is an attractive strategy to enhance the photocatalytic performance of polymeric ***,dibenzothiophene(DBT)-4-carbaldehyde as the precursor is introduced into g-C_(3)N_(4)(TCN)prepared by two-step thermal polymerization to construct an intramolecular D-A type copolymer(TCN-DBT_(x)).DFT calculation and experimental results reveal that DBT plays the role of electron donor unit to modify g-C_(3)N_(4).The incorporation of DBT not only adjusts the band gap to improve reduction ability,but also induces an internal electric field with extendingπ-conjugated system for effective charge *** a result,TCN-DBT_(x)exhibits much better photocatalytic performance with an optimal hydrogen production rate of 3334μmol h^(-1)g^(-1),which is 2.5 times that of *** work provides a protocol for preparing high-performance g-C_(3)N_(4)-based photocatalysts toward various applications.
Photocatalytic reduction of CO_(2)has attracted considerable interest owing to its potential to resolve the energy and environmental ***,the lack of proficient photocatalysts has restricted the application of solar-dr...
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Photocatalytic reduction of CO_(2)has attracted considerable interest owing to its potential to resolve the energy and environmental ***,the lack of proficient photocatalysts has restricted the application of solar-driven photocatalytic CO_(2)***,we reported an S-scheme heterojunction by combining g-C_(3)N_(4)with La^(3+)and Rh^(3+)co-doped SrTiO_(3)through the electrostatic self-assembly method for the efficient photocatalytic CO_(2)*** comparison with g-C_(3)N_(4),the asprepared CN/LRSTO-30 wt%S-scheme heterojunction not only possesses a broadened visible-light response due to the defect states in La,Rh co-doped SrTiO_(3)induced by codoped La^(3+)and Rh^(3+)but also has more adsorption sites for the capture and activation of CO_(2)***,separation and transfer efficiency of the photoinduced charge carriers is much enhanced in the CN/LRSTO-30wt%S-scheme heterojunction via its robust internal electric field,which is firmly demonstrated by in situ irradiation X-ray photoelectron spectroscopy ***,the prepared S-scheme heterojunction achieves impressive photocatalytic CO_(2)reduction performance with an average CO and CH4 evolution rate of4.1-1.8μmol·g^(-1)·h^(-1),respectively,which are~1.9 and~22.5-fold higher than those of pure g-C_(3)N_(4).This study provides innovative perspectives on the design of creative S-scheme heterojunctions for applications in photocatalytic CO_(2)reduction.
The(TiNbTaZrHf)C high entropy carbide(HEC)was successfully synthesized by complete commercial transition metal powders,obtained fine sintered bulks without additives by in-situ reaction element synthesis method.(TiNbT...
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The(TiNbTaZrHf)C high entropy carbide(HEC)was successfully synthesized by complete commercial transition metal powders,obtained fine sintered bulks without additives by in-situ reaction element synthesis method.(TiNbTaZrHf)C bulk shows a face centered cubic rock salt structure with homogeneous single-phase FCC structure in composition and *** optimum sintering temperature is about 1900℃at which the best mechanical properties are *** mechanical properties of(TiNbTaZrHf)C ceramic block are better than those of binary transition metal carbides,and it has obvious high entropy *** a small amount of Al as sintering additive,the mechanical properties of(TiNbTaZrHf)C ceramics continue to improve,the bending strength of the samples at each temperature is increased by at least 38%,and the highest is 486 *** elastic modulus and hardness of the sample at 1900℃are also slightly increased by 4%and 14%,*** above conclusions illustrate that the properties of high entropy ceramics are greatly improved by in-situ reaction sintering.
Two isomeric fluorene-based heteroundecenes of bis(thienocyclopenthieno[3,2-b]thieno)fluorene(BT2T-F)and bis(dithieno[3,2-b:2’,3’-d]thiophene)cyclopentafluorene(B3T-F)have been designed and *** side chains of 4-hexy...
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Two isomeric fluorene-based heteroundecenes of bis(thienocyclopenthieno[3,2-b]thieno)fluorene(BT2T-F)and bis(dithieno[3,2-b:2’,3’-d]thiophene)cyclopentafluorene(B3T-F)have been designed and *** side chains of 4-hexylphenyl anchor on the 5th and 8th positions in B3T-F while on the 4th and 9th positions in BT2T-F,in which the former is closer to the center of the fused *** corresponding acceptor-donor-acceptor(A-D-A)type small molecule acceptors(SMAs)of BT2T-FIC and B3T-FIC were prepared by linking BT2T-F and B3T-F as fused ring donor units with the acceptor unit of 2-(5,6-difluoro-3-oxo-2,3-dihydroinden-1-ylidene)malononitrile(IC-2F),respectively.B3T-FIC presents a superior crystallinity with intense face-on π-π stacking in its neat film while BT2T-FIC is more *** blended with PBDB-T-2Cl as a polymer donor,the optimized PBDB-T-2Cl:BT2T-FIC device exhibits an averaged power conversion efficiency(PCE)of 10.56%while only 7.53%in the PBDB-T-2Cl:B3T-FIC *** improved short-circuit current(J_(sc))and fill factor(FF)of the PBDB-T-2Cl:BT2T-FIC device are the main contribution of its higher performance,which is attributed to its more efficient and balanced charge transport and better carrier recombination *** that BT2T-FIC blend and B3T-FIC blend films both take a preferential face-on orientatedπ-πstacking with comparable distances,the suitable SMA domain size obtained in the BT2T-FIC blend could account for its more efficient photovoltaic *** results highlight the importance of side-chain strategy in developing efficient SMAs with huge fused ring cores.
High entropy boride ceramics have great potential as structural materials serving in extreme ***,their applications are limited by the difficulty of *** the present study,dense(Ti_(0.2)Zr_(0.2)Hf_(0.2)Nb_(0.2)Ta_(0.2)...
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High entropy boride ceramics have great potential as structural materials serving in extreme ***,their applications are limited by the difficulty of *** the present study,dense(Ti_(0.2)Zr_(0.2)Hf_(0.2)Nb_(0.2)Ta_(0.2))B_(2)ceramics with B_(4)C additions were prepared through pressureless sintering at as low as 1900℃.Calculations based on the CALPHAD approach predict that(Ti_(0.2)Zr_(0.2)Hf_(0.2)Nb_(0.2)Ta_(0.2))B_(2)starts to melt at about 3315℃whilst B_(4)C additions reduce the temperature and broaden the tempera-ture region where solid and liquid *** showed that the introduction of B_(4)C could trigger the densification of(Ti_(0.2)Zr_(0.2)Hf_(0.2)Nb_(0.2)Ta_(0.2))B_(2)at a lower temperature and promote their densification *** relative density of samples with 5 wt%of B_(4)C additions sintered at 1900 and 2000℃was 97.7%and 99.7%,*** the sintering temperature was further increased to 2100℃,the liquid phase was reactively formed,leading to the rapid grain coarsening in samples with B_(4)C *** by well-dispersed B_(4)C grains,the sample with 5 wt%B_(4)C sintered at 2000℃exhibited excellent mechanical properties with the Vickers hardness,flexural strength,and fracture toughness of 21.07±2.09 GPa,547±45 MPa,and 5.24±0.14 MPa m^(1/2),which are comparable or even higher than counterparts sintered under pressure.
This study proposed a tung-oil based magnetic targeted delivery microcapsules (MDTMs) to enhance the efficiency of self-healing coatings (SHC).Magnetic particles were used as function particles and emulsifier in s...
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This study proposed a tung-oil based magnetic targeted delivery microcapsules (MDTMs) to enhance the efficiency of self-healing coatings (SHC).Magnetic particles were used as function particles and emulsifier in synthesis of microcapsules (MC).DSC,OM,SEM,TEM,VSM,NSS,EIS and SKP were used to characterize the compounds,structure,healing behavior and anti-corrosion *** indicate that magnetically driven SHC (MD-SHC) reduces 50%migration path of the released tung oil,and increases the release rate of tung oil after the coating is mechanically *** and EIS results suggest that the healing part has impressive anti-corrosion performance,scratches were filled with a large amount of tung oil in a short time,and the released tung oil had formed a complete oil film on scratches at 24 h with higher polarization resistance (Rp).Rpof MD-SHC(2.5×10~5–3.6×10~5Ωcm2) is 2.0–2.8 times of that the SHC (1.1×10~5–1.8×10~5Ωcm2).The enrichment in MD-SHC at the interface decreases bonding strength from 7 to 4.5 MPa as the mass additive of microcapsules reaches 15 wt.%.The current work proves the effectiveness of MD-SHC in improving self-healing ability.
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