Lithium-ion batteries(LIBs) and sodium-ion batteries(SIBs) have received much attention in energy storage system. In particular, among the great efforts on enhancing the performance of LIBs and SIBs, yolk–shell(YS) s...Lithium-ion batteries(LIBs) and sodium-ion batteries(SIBs) have received much attention in energy storage system. In particular, among the great efforts on enhancing the performance of LIBs and SIBs, yolk–shell(YS) structured materials have emerged as a promising strategy toward improving lithium and sodium storage. YS structures possess unique interior void space, large surface area and short diffusion distance, which can solve the problems of volume expansion and aggregation of anode materials, thus enhancing the performance of LIBs and SIBs. In this review, we present a brief overview of recent advances in the novel YS structures of spheres, polyhedrons and rods with controllable morphology and compositions. Enhanced electrochemical performance of LIBs and SIBs based on these novel YS structured anode materials was discussed in detail.展开更多
Non-spherical Cu@Cu S yolk–shell structures are successfully obtained using Cu_2 O cube templates in a process combining rapid surface sulfidation followed by disproportionation of the Cu_2 O core upon treatment with...Non-spherical Cu@Cu S yolk–shell structures are successfully obtained using Cu_2 O cube templates in a process combining rapid surface sulfidation followed by disproportionation of the Cu_2 O core upon treatment with a hydrochloric acid solution. By employing the above method,Cu@Cu S yolk–shell structures with different morphologies,including octahedral, truncated octahedral, and cuboctahedral shapes, can be synthesized. The void space within the hollow structures provides a unique confined space, where the metallic copper present in the core of a shell can be protected from agglomeration and oxidation. Furthermore,the presence of metal copper in these hollow structurescontributes to improvement in the photocatalytic properties of these materials. The application of these Cu@Cu S structures indeed shows clearly improved photocatalytic performance.展开更多
A facile strategy to fabricate gold nanorod@polyacrylic acid/calcium phosphate(Au NR@-PAA/Ca P) yolk–shell nanoparticles(NPs) composed with a PAA/Ca P shell and an Au NR yolk is reported. The asobtained Au NR@PAA/Ca ...A facile strategy to fabricate gold nanorod@polyacrylic acid/calcium phosphate(Au NR@-PAA/Ca P) yolk–shell nanoparticles(NPs) composed with a PAA/Ca P shell and an Au NR yolk is reported. The asobtained Au NR@PAA/Ca P yolk–shell NPs possess ultrahigh doxorubicin(DOX) loading capability(1 mg DOX/mg NPs), superior photothermal conversion property(26%)and p H/near-infrared(NIR) dual-responsive drug delivery performance. The released DOX continuously increased due to the damage of the Ca P shell at low p H values. When the DOX-loaded Au NR@PAA/Ca P yolk–shell NPs wereexposed to NIR irradiation, a burst-like drug release occurs owing to the heat produced by the Au NRs. Furthermore,Au NR@PAA/Ca P yolk–shell NPs are successfully employed for synergic dual-mode X-ray computed tomography/photoacoustic imaging and chemo-photothermal cancer therapy. Therefore, this work brings new insights for the synthesis of multifunctional nanomaterials and extends theranostic applications.展开更多
A yolk-shell structured Co-C/Void/CogS8 ternary composite composed of a Co nanoparticle-embedded porous carbon core and Co9S8 shell was synthesized by the sulfidation of a Co-based zeolitic imidazolate framework and s...A yolk-shell structured Co-C/Void/CogS8 ternary composite composed of a Co nanoparticle-embedded porous carbon core and Co9S8 shell was synthesized by the sulfidation of a Co-based zeolitic imidazolate framework and subsequent pyrolysis. The composition and interior cavity of the Co-C/Void/CogS8 composite could be precisely modulated by controlling the sulfidation reaction. Due to the abundant heterointerfaces, well-controlled cavity, and magnetic-dielectric synergistic effects, the Co-C/Void/CogS8 exhibited excellent and tunable microwave- absorbing properties. The optimized Co-C/Void/Cog~ having a loading of 25 wt.% and thickness only 2.2 mm, displayed an ultrabroad absorption bandwidth of 8.2 GHz at high frequencies. Moreover, the composite could achieve an extremely high reflection loss of -54.02 dB at low frequencies by adjusting its loading to 30 wt.%. This study provides a new insight into promising lightweight microwave-absorbing materials with ultrabroad absorption bandwidths and strong low-frequency absorption.展开更多
Yolk-shell architectures have attracted extensive attention owing to their unique structure and infusive applications. MoS2 is regarded as one of the most promising catalytic materials for hydrogen evolution by the sp...Yolk-shell architectures have attracted extensive attention owing to their unique structure and infusive applications. MoS2 is regarded as one of the most promising catalytic materials for hydrogen evolution by the splitting of water. In this work, a simple self-template solvothermal approach is developed for the synthesis of novel MoS2 yolk-shell microspheres with a hierarchical porous structure by reacting MoO2 microspheres with L-cysteine. A dissolution- recrystallization formation mechanism is proposed for the MoS2 yolk-shell microspheres. Owing to structural superiority, the new material architecture exhibits improved photoelectrochemical properties, including efficient hydrogen evolution reaction catalytic activities, a high photocurrent density, a small overpotential, and a low charge-transfer resistance.展开更多
Hierarchical yolk-shell structured cathodes with controllable composition are potentially attractive materials for the fabrication of lithium-ion batteries, but they are difficult to synthesize. In this work, we prese...Hierarchical yolk-shell structured cathodes with controllable composition are potentially attractive materials for the fabrication of lithium-ion batteries, but they are difficult to synthesize. In this work, we present a simple, scalable, and general morphology-inheritance strategy to synthesize spinel manganese cathodes with a hierarchical yolk-shell structure. Starting from uniform Mn carbonate spheres prepared by an ultrafast and scalable microwave-assisted method, we show that the subsequent sintering results in the formation of Mn203 precursors with a yolk-shell structure, which can be effectively transferred to spinel manganese cathodes via simple impregnation and solid-state reaction. Owing to the simple and scalable nature of the present strategy, materials prepared through this approach have great potential as cathodes of lithium-ion batteries, where they can lead to high specific capacity, outstanding cyclability, and superior rate capability. In particular, both LiMn204 and LiNi05Mn1504 with hierarchical yolk-shell structure achieved nearly theoretical capacity, without any apparent decay after 100 cycles at I C. Moreover, 80% of the initial discharge capacities of both samples can be maintained for up to 500 cycles at a high rate of 10 C.展开更多
Transition-metal oxides （TMOs） have gradually attracted attention from resear- chers as anode materials for lithium-ion batteries （LIBs） and sodium-ion batteries （SIBs） because of their high theoretical capacity...Transition-metal oxides （TMOs） have gradually attracted attention from resear- chers as anode materials for lithium-ion batteries （LIBs） and sodium-ion batteries （SIBs） because of their high theoretical capacity. However, their poor cycling stability and inferior rate capability resulting from the large volume variation during the lithiation/sodiation process and their low intrinsic electronic con- ductivity limit their applications. To solve the problems of TMOs, carbon-based metal-oxide composites with complex structures derived from metal-organic frameworks （MOFs） have emerged as promising electrode materials for LIBs and SIBs. In this study, we adopted a facile interface-modulated method to synthesize yolk-shell carbon-based Co3O4 dodecahedrons derived from ZIF-67 zeolitic imida- zolate frameworks. This strategy is based on the interface separation between the ZIF-67 core and the carbon-based shell during the pyrolysis process. The unique yolk-shell structure effectively accommodates the volume expansion during lithiation or sodiation, and the carbon matrix improves the electrical conductivity of the electrode. As an anode for LIBs, the yolk-shell Co3O4/C dodecahedrons exhibit a high specific capacity and excellent cycling stability （1,100 mAh.g-1 after 120 cycles at 200 mA-g-1）. As an anode for S1Bs, the composites exhibit an outstand- ing rate capability （307 mAh-g-1 at 1,000 mA-g-1 and 269 mAh.g-1 at 2,000 mA-g-1）. Detailed electrochemical kinetic analysis indicates that the energy storage for Li＋ and Na＋ in yolk-sheU Co3O4/C dodecahedrons shows a dominant capacitive behavior. This work introduces an effective approach for fabricating carbon- based metal-oxide composites by using MOFs as ideal precursors and as electrode materials to enhance the electrochemical performance of LIBs and SIBs.展开更多
基金supported by National Program on Key Basic Research Project (973 Program) No. 2013CB933301National Natural Science Foundation of China No. 51272038 and 61474015
文摘Lithium-ion batteries(LIBs) and sodium-ion batteries(SIBs) have received much attention in energy storage system. In particular, among the great efforts on enhancing the performance of LIBs and SIBs, yolk–shell(YS) structured materials have emerged as a promising strategy toward improving lithium and sodium storage. YS structures possess unique interior void space, large surface area and short diffusion distance, which can solve the problems of volume expansion and aggregation of anode materials, thus enhancing the performance of LIBs and SIBs. In this review, we present a brief overview of recent advances in the novel YS structures of spheres, polyhedrons and rods with controllable morphology and compositions. Enhanced electrochemical performance of LIBs and SIBs based on these novel YS structured anode materials was discussed in detail.
基金supported by the National Natural Science Foundation of China (Grant Nos. 21671085, 21473081, 21201088)the Natural Science Foundation of Jiangsu Province (BK20161160)the Qing Lan Project and the Project Funded by the Priority Academic Program Development of Jiangsu Higher Education Institutions
文摘Non-spherical Cu@Cu S yolk–shell structures are successfully obtained using Cu_2 O cube templates in a process combining rapid surface sulfidation followed by disproportionation of the Cu_2 O core upon treatment with a hydrochloric acid solution. By employing the above method,Cu@Cu S yolk–shell structures with different morphologies,including octahedral, truncated octahedral, and cuboctahedral shapes, can be synthesized. The void space within the hollow structures provides a unique confined space, where the metallic copper present in the core of a shell can be protected from agglomeration and oxidation. Furthermore,the presence of metal copper in these hollow structurescontributes to improvement in the photocatalytic properties of these materials. The application of these Cu@Cu S structures indeed shows clearly improved photocatalytic performance.
基金the National Natural Science Foundation of China(Grant Nos.21573040 and 21603029)the Natural Science Foundation and Science and Technology Development Planning of Jilin Province(20150204086GX and20170520148JH)+3 种基金the Fundamental Research Funds for the Central Universities(2412016KJ007 and 2412016KJ020)the China Postdoctoral Science Foundation(2016M600224)the Jilin Provincial Research Foundation for Basic Research(20160519012JH)Jilin Provincial Key Laboratory of Advanced Energy Materials(Northeast Normal University)
文摘A facile strategy to fabricate gold nanorod@polyacrylic acid/calcium phosphate(Au NR@-PAA/Ca P) yolk–shell nanoparticles(NPs) composed with a PAA/Ca P shell and an Au NR yolk is reported. The asobtained Au NR@PAA/Ca P yolk–shell NPs possess ultrahigh doxorubicin(DOX) loading capability(1 mg DOX/mg NPs), superior photothermal conversion property(26%)and p H/near-infrared(NIR) dual-responsive drug delivery performance. The released DOX continuously increased due to the damage of the Ca P shell at low p H values. When the DOX-loaded Au NR@PAA/Ca P yolk–shell NPs wereexposed to NIR irradiation, a burst-like drug release occurs owing to the heat produced by the Au NRs. Furthermore,Au NR@PAA/Ca P yolk–shell NPs are successfully employed for synergic dual-mode X-ray computed tomography/photoacoustic imaging and chemo-photothermal cancer therapy. Therefore, this work brings new insights for the synthesis of multifunctional nanomaterials and extends theranostic applications.
文摘A yolk-shell structured Co-C/Void/CogS8 ternary composite composed of a Co nanoparticle-embedded porous carbon core and Co9S8 shell was synthesized by the sulfidation of a Co-based zeolitic imidazolate framework and subsequent pyrolysis. The composition and interior cavity of the Co-C/Void/CogS8 composite could be precisely modulated by controlling the sulfidation reaction. Due to the abundant heterointerfaces, well-controlled cavity, and magnetic-dielectric synergistic effects, the Co-C/Void/CogS8 exhibited excellent and tunable microwave- absorbing properties. The optimized Co-C/Void/Cog~ having a loading of 25 wt.% and thickness only 2.2 mm, displayed an ultrabroad absorption bandwidth of 8.2 GHz at high frequencies. Moreover, the composite could achieve an extremely high reflection loss of -54.02 dB at low frequencies by adjusting its loading to 30 wt.%. This study provides a new insight into promising lightweight microwave-absorbing materials with ultrabroad absorption bandwidths and strong low-frequency absorption.
基金This work received financial support from the Dean Fund of Chinese Academy of Inspection and Quaran- tine （No. 2016JK025）, the Science Foundation of Administration of Quality Supervision, Inspection and Quarantine （AQSIQ） （No. 2015IK308）, and the National Natural Science Foundation of China （No. 51472226）.
文摘Yolk-shell architectures have attracted extensive attention owing to their unique structure and infusive applications. MoS2 is regarded as one of the most promising catalytic materials for hydrogen evolution by the splitting of water. In this work, a simple self-template solvothermal approach is developed for the synthesis of novel MoS2 yolk-shell microspheres with a hierarchical porous structure by reacting MoO2 microspheres with L-cysteine. A dissolution- recrystallization formation mechanism is proposed for the MoS2 yolk-shell microspheres. Owing to structural superiority, the new material architecture exhibits improved photoelectrochemical properties, including efficient hydrogen evolution reaction catalytic activities, a high photocurrent density, a small overpotential, and a low charge-transfer resistance.
文摘Hierarchical yolk-shell structured cathodes with controllable composition are potentially attractive materials for the fabrication of lithium-ion batteries, but they are difficult to synthesize. In this work, we present a simple, scalable, and general morphology-inheritance strategy to synthesize spinel manganese cathodes with a hierarchical yolk-shell structure. Starting from uniform Mn carbonate spheres prepared by an ultrafast and scalable microwave-assisted method, we show that the subsequent sintering results in the formation of Mn203 precursors with a yolk-shell structure, which can be effectively transferred to spinel manganese cathodes via simple impregnation and solid-state reaction. Owing to the simple and scalable nature of the present strategy, materials prepared through this approach have great potential as cathodes of lithium-ion batteries, where they can lead to high specific capacity, outstanding cyclability, and superior rate capability. In particular, both LiMn204 and LiNi05Mn1504 with hierarchical yolk-shell structure achieved nearly theoretical capacity, without any apparent decay after 100 cycles at I C. Moreover, 80% of the initial discharge capacities of both samples can be maintained for up to 500 cycles at a high rate of 10 C.
基金This work was supported by the National Key Research and Development Program of China （No. 2016YFA0202603）, the National Basic Research Program of China （No. 2013CB934103）, the National Natural Science Foundation of China （Nos. 51521001 and 51272197）, the National Natural Science Fund for Distinguished Young Scholars （No. 51425204）, the Fundamental Research Funds for the Central Universities （WUT： 22016III001, 2017IVA096） and the Foundation of National Excellent Doctoral Dissertation of PR China （No. 2016-YB-004） Prof. Liqiang Mai gratefully acknowledges the financial support from China Scholarship Council （No. 201606955096）.
文摘Transition-metal oxides （TMOs） have gradually attracted attention from resear- chers as anode materials for lithium-ion batteries （LIBs） and sodium-ion batteries （SIBs） because of their high theoretical capacity. However, their poor cycling stability and inferior rate capability resulting from the large volume variation during the lithiation/sodiation process and their low intrinsic electronic con- ductivity limit their applications. To solve the problems of TMOs, carbon-based metal-oxide composites with complex structures derived from metal-organic frameworks （MOFs） have emerged as promising electrode materials for LIBs and SIBs. In this study, we adopted a facile interface-modulated method to synthesize yolk-shell carbon-based Co3O4 dodecahedrons derived from ZIF-67 zeolitic imida- zolate frameworks. This strategy is based on the interface separation between the ZIF-67 core and the carbon-based shell during the pyrolysis process. The unique yolk-shell structure effectively accommodates the volume expansion during lithiation or sodiation, and the carbon matrix improves the electrical conductivity of the electrode. As an anode for LIBs, the yolk-shell Co3O4/C dodecahedrons exhibit a high specific capacity and excellent cycling stability （1,100 mAh.g-1 after 120 cycles at 200 mA-g-1）. As an anode for S1Bs, the composites exhibit an outstand- ing rate capability （307 mAh-g-1 at 1,000 mA-g-1 and 269 mAh.g-1 at 2,000 mA-g-1）. Detailed electrochemical kinetic analysis indicates that the energy storage for Li＋ and Na＋ in yolk-sheU Co3O4/C dodecahedrons shows a dominant capacitive behavior. This work introduces an effective approach for fabricating carbon- based metal-oxide composites by using MOFs as ideal precursors and as electrode materials to enhance the electrochemical performance of LIBs and SIBs.
