Two-dimensional(2D)materials have come to light due to their unique thickness that owns abundant exposed edges with enhanced electrocatalytic properties.2D molybdenum disulfide(MoS_(2))nanosheet has aroused considerab...Two-dimensional(2D)materials have come to light due to their unique thickness that owns abundant exposed edges with enhanced electrocatalytic properties.2D molybdenum disulfide(MoS_(2))nanosheet has aroused considerable attention due to its tunable surface chemistry and high electrochemical sur-face area.Nonetheless,several shortcomings associated with MoS_(2),such as its naturally existing semi-conducting 2H phase,which has limited active sites due to the inert basal plane,restrict its application in water electrocatalysis.Taking into account the benefits of the 1T/2H phase of MoS_(2),as well as the importance of engineering 2D/2D heterojunction interface for boosted electrocatalysis,metallic Ti_(3)C_(2)Tx was integrated with 1T/2H MoS_(2) to develop 2D/2D 1T/2H MoS_(2)/Ti_(3)C_(2)Tx heterostructured nanocompos-ites.Herein,with only 25%of the intercalating agent,1T/2H MoS_(2) with the highest 1T phase content of~82%was successfully synthesized.It was further incorporated with 1 wt%of Ti_(3)C_(2)Tx through a com-bination of ultrasonication and mechanical stirring process.The 1T/2H MoS_(2)(25D)/Ti_(3)C_(2)Tx-1(MTC-1)manifested outstanding electrocatalytic performance with an overpotential and Tafel slope of 280 mV(83.80 mV dec^(-1))and 300 mV(117.2 mV dec^(-1)),for catalyzing acidic and alkaline medium HER,respec-tively.Pivotally,the as-prepared catalysts also illustrated long-term stability for more than 40 h.The coupling method for the 2D nanosheets is crucial to suppress the oxidation of Ti_(3)C_(2)Tx and the restack-ing issue of 2D nanosheets.The superior HER activity is ascribed to the synergistic effect between the heterostructure,enhancing the electronic structure and charge separation capability.The intrinsic prop-erty of the catalyst further confirms by turnover frequency(TOF)calculation.As such,this research paves the way for designing high-efficiency 2D electrocatalysts and sheds light on the further advancement of tunable 2D electrocatalysts for robust water splitting and beyond.展开更多
Magnesium(Mg)stands out in temporary biomaterial applications due to its biocompatibility,biodegradability,and low Young’s modulus.However,controlling its corrosion through next-generation polymer-based functional co...Magnesium(Mg)stands out in temporary biomaterial applications due to its biocompatibility,biodegradability,and low Young’s modulus.However,controlling its corrosion through next-generation polymer-based functional coatings is crucial due to the rapid degradation behavior of Mg.In this study,the function of 2D lamellar Ti_(3)C_(2)T_(x)(MXene)in Hydroxyapatite(HA)and Halloysite nanotube(HNT)hybrid coatings in biodegradable poly-(lactic acid)(PLA)was investigated.The morphological and structural characterizations of the coatings on Mg were revealed through HRTEM,XPS,SEM-EDX,XRD,FTIR,and contact angle analyses/tests.Electrochemical in vitro corrosion tests(OCP,PDS,and EIS-Nyquist)were conducted for evaluate corrosion resistance under simulated body fluid(SBF)conditions.The bioactivity of the coatings in SBF have been revealed in accordance with the ISO 23,317 standard.Finally,antibacterial disk diffusion tests were conducted to investigate the functional effect of MXene in coatings.It has been determined that the presence of MXene in the coating increased not only surface wettability(131°,85°,77°,and 74°for uncoated,pH,PHH,and PHH/MXene coatings,respectively)but also increased corrosion resistance(1857.850,42.357,1.593,and 0.085×10^(-6),A/cm^(2) for uncoated,pH,PHH,and PHH/MXene coatings,respectively).It has been proven that the in vitro bioactivity of PLA-HA coatings is further enhanced by adding HNT and MXene,along with SEM morphologies after SBF.Finally,2D lamellar MXene-filled coating exhibits antibacterial behavior against both E.coli and S.aureus bacteria.展开更多
Cloud point extraction(CPE) utilizing non-ionic surfactant TX114 was carried out to separate and concentrate di(2-ethyl hexyl) phosphoric acid(D2EHPA) in its dilute aqueous solution.The CPE process was facilitated at...Cloud point extraction(CPE) utilizing non-ionic surfactant TX114 was carried out to separate and concentrate di(2-ethyl hexyl) phosphoric acid(D2EHPA) in its dilute aqueous solution.The CPE process was facilitated at 45℃.The influence of TX114 concentration,D2EHPA concentration and solution acidity on the extraction efficiency was studied.The results showed that extraction efficiency increased with decreasing TX114 concentration and increasing D2EHPA concentration.Such unusual extraction behavior might be the result of the reverse-micelle coacervate phase,solublizing D2EHPA on the surface of micelle,and the influence of D2EHPA on the cloud point of TX114.展开更多
基金Ministry of Higher Education(MOHE)Malaysia under the Fundamental Research Grant Scheme(FRGS)(Ref No:FRGS/1/2020/TK0/XMU/02/1)We would also like to thank the Ministry of Science,Technology and Innovation(MOSTI)Malaysia under the Strategic Research Fund(SRF-APP)(S.22015)+5 种基金The authors would also like to acknowledge the financial support provided by the National Natural Science Foundation of China(Ref No.22202168)Guangdong Basic and Applied Basic Re-search Foundation(Ref No.2021A1515111019)We would also like to acknowledge the financial support from the State Key Labo-ratory of Physical Chemistry of Solid Surfaces,Xiamen University(No.2023X11)This work is also funded by Xiamen University Malaysia Investigatorship Grant(Grant No.IENG/0038)Xiamen University Malaysia Research Fund(ICOE/0001,XMUMRF/2021-C8/IENG/0041 and XMUMRF/2019-C3/IENG/0013)Hengyuan International Sdn.Bhd.(Grant No.EENG/0003).
文摘Two-dimensional(2D)materials have come to light due to their unique thickness that owns abundant exposed edges with enhanced electrocatalytic properties.2D molybdenum disulfide(MoS_(2))nanosheet has aroused considerable attention due to its tunable surface chemistry and high electrochemical sur-face area.Nonetheless,several shortcomings associated with MoS_(2),such as its naturally existing semi-conducting 2H phase,which has limited active sites due to the inert basal plane,restrict its application in water electrocatalysis.Taking into account the benefits of the 1T/2H phase of MoS_(2),as well as the importance of engineering 2D/2D heterojunction interface for boosted electrocatalysis,metallic Ti_(3)C_(2)Tx was integrated with 1T/2H MoS_(2) to develop 2D/2D 1T/2H MoS_(2)/Ti_(3)C_(2)Tx heterostructured nanocompos-ites.Herein,with only 25%of the intercalating agent,1T/2H MoS_(2) with the highest 1T phase content of~82%was successfully synthesized.It was further incorporated with 1 wt%of Ti_(3)C_(2)Tx through a com-bination of ultrasonication and mechanical stirring process.The 1T/2H MoS_(2)(25D)/Ti_(3)C_(2)Tx-1(MTC-1)manifested outstanding electrocatalytic performance with an overpotential and Tafel slope of 280 mV(83.80 mV dec^(-1))and 300 mV(117.2 mV dec^(-1)),for catalyzing acidic and alkaline medium HER,respec-tively.Pivotally,the as-prepared catalysts also illustrated long-term stability for more than 40 h.The coupling method for the 2D nanosheets is crucial to suppress the oxidation of Ti_(3)C_(2)Tx and the restack-ing issue of 2D nanosheets.The superior HER activity is ascribed to the synergistic effect between the heterostructure,enhancing the electronic structure and charge separation capability.The intrinsic prop-erty of the catalyst further confirms by turnover frequency(TOF)calculation.As such,this research paves the way for designing high-efficiency 2D electrocatalysts and sheds light on the further advancement of tunable 2D electrocatalysts for robust water splitting and beyond.
文摘Magnesium(Mg)stands out in temporary biomaterial applications due to its biocompatibility,biodegradability,and low Young’s modulus.However,controlling its corrosion through next-generation polymer-based functional coatings is crucial due to the rapid degradation behavior of Mg.In this study,the function of 2D lamellar Ti_(3)C_(2)T_(x)(MXene)in Hydroxyapatite(HA)and Halloysite nanotube(HNT)hybrid coatings in biodegradable poly-(lactic acid)(PLA)was investigated.The morphological and structural characterizations of the coatings on Mg were revealed through HRTEM,XPS,SEM-EDX,XRD,FTIR,and contact angle analyses/tests.Electrochemical in vitro corrosion tests(OCP,PDS,and EIS-Nyquist)were conducted for evaluate corrosion resistance under simulated body fluid(SBF)conditions.The bioactivity of the coatings in SBF have been revealed in accordance with the ISO 23,317 standard.Finally,antibacterial disk diffusion tests were conducted to investigate the functional effect of MXene in coatings.It has been determined that the presence of MXene in the coating increased not only surface wettability(131°,85°,77°,and 74°for uncoated,pH,PHH,and PHH/MXene coatings,respectively)but also increased corrosion resistance(1857.850,42.357,1.593,and 0.085×10^(-6),A/cm^(2) for uncoated,pH,PHH,and PHH/MXene coatings,respectively).It has been proven that the in vitro bioactivity of PLA-HA coatings is further enhanced by adding HNT and MXene,along with SEM morphologies after SBF.Finally,2D lamellar MXene-filled coating exhibits antibacterial behavior against both E.coli and S.aureus bacteria.
文摘Cloud point extraction(CPE) utilizing non-ionic surfactant TX114 was carried out to separate and concentrate di(2-ethyl hexyl) phosphoric acid(D2EHPA) in its dilute aqueous solution.The CPE process was facilitated at 45℃.The influence of TX114 concentration,D2EHPA concentration and solution acidity on the extraction efficiency was studied.The results showed that extraction efficiency increased with decreasing TX114 concentration and increasing D2EHPA concentration.Such unusual extraction behavior might be the result of the reverse-micelle coacervate phase,solublizing D2EHPA on the surface of micelle,and the influence of D2EHPA on the cloud point of TX114.
