Lithium-rich manganese-based oxides have the advantages of high discharge specific capacity, so they are potential candidates for advanced lithium battery cathode materials. However, they also have drawbacks to be sol...Lithium-rich manganese-based oxides have the advantages of high discharge specific capacity, so they are potential candidates for advanced lithium battery cathode materials. However, they also have drawbacks to be solved such as serious irreversible loss of capacity and voltage decay in the cycling process. Surface coating method was used in this paper to modify the lithium-rich manganese-based oxide(LRMO,Li_(1.2)Mn_(0.54)Ni_(0.13)Co_(0.13)O_(2)) to improve its electrochemical properties. Zirconium-based compounds coated LRMO materials(ZBC@LRMO) were obtained via the reaction of lithium hydroxide with zirconium n-butanol and subsequent thermal treatment at different temperatures. The results of X-ray diffraction and transmission electron microscopy confirm that the crystal structure and composition of the ZBC coating layer vary with the calcination temperature. The coating layer obtained at 600 ℃ is composed of tetragonal ZrO_(2) and Li_(2)ZrO_(3). The ZBC@LRMO sample with tetragonal ZrO =2 and Li_(2)ZrO_(3) composite exhibits the best electrochemical performance: the discharge capacity of ZBC@LRMO can reach 296 mAh g^(-1) at 0.1 C and 120 mAh g^(-1) at high rate of 5 C.展开更多
Zirconium-based metallic glasses(Zr-MGs)are demonstrated to exhibit high mechanical strength,low elastic modulus and excellent biocompatibility,making them promising materials for endosseous implants.Meanwhile,tantalu...Zirconium-based metallic glasses(Zr-MGs)are demonstrated to exhibit high mechanical strength,low elastic modulus and excellent biocompatibility,making them promising materials for endosseous implants.Meanwhile,tantalum(Ta)is also well known for its ideal corrosion resistance and biological effects.However,the metal has an elastic modulus as high as 186 GPa which is not comparable to the natural bone(10–30 GPa),and it also has a relative high cost.Here,to fully exploit the advantages of Ta as endosseous implants,a small amount of Ta(as low as 3 at.%)was successfully added into a Zr-MG to generate an advanced functional endosseous implant,Zr58Cu25Al14Ta3 MG,with superior comprehensive properties.Upon carefully dissecting the atomic structure and surface chemistry,the results show that amorphization of Ta enables the uniform distribution in material surface,leading to a significantly improved chemical stability and extensive material-cell contact regulation.Systematical analyses on the immunological,angiogenesis and osteogenesis capability of the material are carried out utilizing the next-generation sequencing,revealing that Zr_(58)Cu_(25)Al_(14)Ta_(3)MG can regulate angiogenesis through VEGF signaling pathway and osteogenesis via BMP signaling pathway.Animal experiment further confirms a sound osseointegration of Zr_(58)Cu_(25)Al_(14)Ta_(3)MG in achieving better bone-implant-contact and inducing faster periimplant bone formation.展开更多
Integration of single-atom catalysts(SACs) onto metal-organic frameworks(MOFs) with porous channels has garnered significant interest in the field of CO_(2) reduction.However,MOFs are usually bulky can impede the diff...Integration of single-atom catalysts(SACs) onto metal-organic frameworks(MOFs) with porous channels has garnered significant interest in the field of CO_(2) reduction.However,MOFs are usually bulky can impede the diffusion of intermediates with substrates and maximizing catalytic site utilization remains a challenge.In this study,we utilized firstly the post-synthetic single-atom chelation sites on zirconiumbased metal-organic cages(Zr-MOCs) to anchor cobalt(Co) atom to synthesize single-dispersible Zr T^(-1)-NH_(2)-IS-Co molecular cages for CO_(2) photoreduction.Experimental results demonstrate that Zr T^(-1)-NH_(2)-ISCo exhibits impressive catalytic performance,achieving syngas yields of up to 30.9 mmol g^(-1)h^(-1),ranking among the highest values of reported crystalline porous catalysts.Mechanistic insights reveal the newly introduced metal serving as the catalytic site and ^(*)COOH acts as a crucial intermediate in the CO_(2) reduction process.Furthermore,the successful synthesis of Zr T^(-1)-NH_(2)-IS-Ni and Zr T^(-1)-NH_(2)-IS-Mn show the universality of the modification strategies,with their CO_(2) catalytic activity surpassing that of Zr T^(-1)-NH_(2).展开更多
Zirconium-based metal-organic cages(Zr-MOCs)typically exhibit high stability,but their structural and application reports are scarce due to stringent crystallization conditions.We have successfully fluorinated the cla...Zirconium-based metal-organic cages(Zr-MOCs)typically exhibit high stability,but their structural and application reports are scarce due to stringent crystallization conditions.We have successfully fluorinated the classical Zr-MOCs(ZrT-3)for the first time,obtaining the fluorinated MOCs(ZrT-3-F).Notably,ZrT-3-F not only inherits the high stability of its parent structure,but also acts as a catalyst for the effective oxidation of benzyl thioether for the first time.The reaction can reach a conversion rate of 99%in 6 h,and the selectivity reaches 95%,which far exceeds the non-fluorinated ZrT-3.This work proves that the specific functionalization of the classical Zr-MOCs can further expand their application potential,such as catalysis.展开更多
基金supported by the National Natural Science Foundation of China(No.21776051)the Research Fund Program of Key Laboratory of Fuel Cell Technology of Guangdong Province。
文摘Lithium-rich manganese-based oxides have the advantages of high discharge specific capacity, so they are potential candidates for advanced lithium battery cathode materials. However, they also have drawbacks to be solved such as serious irreversible loss of capacity and voltage decay in the cycling process. Surface coating method was used in this paper to modify the lithium-rich manganese-based oxide(LRMO,Li_(1.2)Mn_(0.54)Ni_(0.13)Co_(0.13)O_(2)) to improve its electrochemical properties. Zirconium-based compounds coated LRMO materials(ZBC@LRMO) were obtained via the reaction of lithium hydroxide with zirconium n-butanol and subsequent thermal treatment at different temperatures. The results of X-ray diffraction and transmission electron microscopy confirm that the crystal structure and composition of the ZBC coating layer vary with the calcination temperature. The coating layer obtained at 600 ℃ is composed of tetragonal ZrO_(2) and Li_(2)ZrO_(3). The ZBC@LRMO sample with tetragonal ZrO =2 and Li_(2)ZrO_(3) composite exhibits the best electrochemical performance: the discharge capacity of ZBC@LRMO can reach 296 mAh g^(-1) at 0.1 C and 120 mAh g^(-1) at high rate of 5 C.
基金supported by the National Natural Science Foundation of China(52035001)National Key R&D Program of China(2019YFB1706904)+3 种基金Beijing Training Project for the Leading Talents in S&T(Z191100006119022)National Key Research and Development Plan(2018YFA0703603)National Science 535 Foundation of China(52192602)Youth Fund of the National Natural Science Foundation of China(82201125).
文摘Zirconium-based metallic glasses(Zr-MGs)are demonstrated to exhibit high mechanical strength,low elastic modulus and excellent biocompatibility,making them promising materials for endosseous implants.Meanwhile,tantalum(Ta)is also well known for its ideal corrosion resistance and biological effects.However,the metal has an elastic modulus as high as 186 GPa which is not comparable to the natural bone(10–30 GPa),and it also has a relative high cost.Here,to fully exploit the advantages of Ta as endosseous implants,a small amount of Ta(as low as 3 at.%)was successfully added into a Zr-MG to generate an advanced functional endosseous implant,Zr58Cu25Al14Ta3 MG,with superior comprehensive properties.Upon carefully dissecting the atomic structure and surface chemistry,the results show that amorphization of Ta enables the uniform distribution in material surface,leading to a significantly improved chemical stability and extensive material-cell contact regulation.Systematical analyses on the immunological,angiogenesis and osteogenesis capability of the material are carried out utilizing the next-generation sequencing,revealing that Zr_(58)Cu_(25)Al_(14)Ta_(3)MG can regulate angiogenesis through VEGF signaling pathway and osteogenesis via BMP signaling pathway.Animal experiment further confirms a sound osseointegration of Zr_(58)Cu_(25)Al_(14)Ta_(3)MG in achieving better bone-implant-contact and inducing faster periimplant bone formation.
基金financially supported by the NSFC of China (Nos.22175033,22371033,22371032)Jilin Provincial Department of Science and Technology (No.20230508108RC)+1 种基金the Fundamental Research Funds for the Central Universities Excellent Youth Team Program (No.2412023YQ001)the Postdoctoral Fellowship Program of CPSF (No.GZC20230939)。
文摘Integration of single-atom catalysts(SACs) onto metal-organic frameworks(MOFs) with porous channels has garnered significant interest in the field of CO_(2) reduction.However,MOFs are usually bulky can impede the diffusion of intermediates with substrates and maximizing catalytic site utilization remains a challenge.In this study,we utilized firstly the post-synthetic single-atom chelation sites on zirconiumbased metal-organic cages(Zr-MOCs) to anchor cobalt(Co) atom to synthesize single-dispersible Zr T^(-1)-NH_(2)-IS-Co molecular cages for CO_(2) photoreduction.Experimental results demonstrate that Zr T^(-1)-NH_(2)-ISCo exhibits impressive catalytic performance,achieving syngas yields of up to 30.9 mmol g^(-1)h^(-1),ranking among the highest values of reported crystalline porous catalysts.Mechanistic insights reveal the newly introduced metal serving as the catalytic site and ^(*)COOH acts as a crucial intermediate in the CO_(2) reduction process.Furthermore,the successful synthesis of Zr T^(-1)-NH_(2)-IS-Ni and Zr T^(-1)-NH_(2)-IS-Mn show the universality of the modification strategies,with their CO_(2) catalytic activity surpassing that of Zr T^(-1)-NH_(2).
基金supported by National Natural Science Foundation of China(Nos.22201046,22371054)Local Innovation Research Team Project of Guangdong Pearl River Talent Plan(No.2017BT01Z032)。
文摘Zirconium-based metal-organic cages(Zr-MOCs)typically exhibit high stability,but their structural and application reports are scarce due to stringent crystallization conditions.We have successfully fluorinated the classical Zr-MOCs(ZrT-3)for the first time,obtaining the fluorinated MOCs(ZrT-3-F).Notably,ZrT-3-F not only inherits the high stability of its parent structure,but also acts as a catalyst for the effective oxidation of benzyl thioether for the first time.The reaction can reach a conversion rate of 99%in 6 h,and the selectivity reaches 95%,which far exceeds the non-fluorinated ZrT-3.This work proves that the specific functionalization of the classical Zr-MOCs can further expand their application potential,such as catalysis.
