Iron disulfide is considered to be a potential anode material for sodium-ion batteries due to its high theoretical capacity. However, its applications are seriously limited by the weak conductivity and large volume ch...Iron disulfide is considered to be a potential anode material for sodium-ion batteries due to its high theoretical capacity. However, its applications are seriously limited by the weak conductivity and large volume change, which results in low reversible capacity and poor cycling stability.Herein, reduced graphene oxide-wrapped FeS_2(FeS_2/rGO)composite was fabricated to achieve excellent electrochemical performance via a facile two-step method. The introduction of rGO effectively improved the conductivity,BET surface area, and structural stability of the FeS_2 active material, thus endowing it with high specific capacity, good rate capability, as well as excellent cycling stability. Electrochemical measurements show that the FeS_2/rGO composite had a high initial discharge capacity of 1263.2 mAh gg^(-1) at 100 mA gg^(-1) and a high discharge capacity of 344 mAh gg^(-1) at 10 A gg^(-1), demonstrating superior rate performance. After 100 cycles at 100 mA gg^(-1),the discharge capacity remained at 609.5 mAh g^(-1), indicating the excellent cycling stability of the FeS_2/rGO electrode.展开更多
Anti-filtration recharge wells are commonly installed in river channels and irrigation canals on the Shandong Peninsula,China,and can be used as an important recharge facility for underground reservoirs.However,during...Anti-filtration recharge wells are commonly installed in river channels and irrigation canals on the Shandong Peninsula,China,and can be used as an important recharge facility for underground reservoirs.However,during recharge,as the running time increases,the recharge capacity gradually decreases.This study was undertaken to develop a new recharge well and mitigate this deficiency.A round empty core infiltration and antifiltration recharge well and laboratory recharge test equipment were developed.Subsequently,1:25 models of the recharge pond,a round empty core recharge wellhead,and an artificial recharge well were prepared.Using equal recharge levels and ambient groundwater levels,laboratory steady-flow recharge tests on the existing anti-filtration recharge well,the new round empty core infiltration and anti-filtration recharge well,and an artificial recharge well were carried out.Experimental data on the measured groundwater table and single-well recharge quantity were also collected and analyzed.The results showed that compared with the existing anti-filtration recharge well,the new round empty core infiltration and anti-filtration recharge well had stronger anti-deposition and anti-scouring properties,and the single-well recharge quantity increased by 403%.With an increase in the number of recharge tests,the single-well recharge quantity gradually decreased and tended to stabilize as a whole.展开更多
基金supported by National Natural Science Foundation of China (51702138, 51702079)Natural Science Foundation of Jiangsu Province (BK20160213)the Priority Academic Program Development of Jiangsu Higher Education Institutions
文摘Iron disulfide is considered to be a potential anode material for sodium-ion batteries due to its high theoretical capacity. However, its applications are seriously limited by the weak conductivity and large volume change, which results in low reversible capacity and poor cycling stability.Herein, reduced graphene oxide-wrapped FeS_2(FeS_2/rGO)composite was fabricated to achieve excellent electrochemical performance via a facile two-step method. The introduction of rGO effectively improved the conductivity,BET surface area, and structural stability of the FeS_2 active material, thus endowing it with high specific capacity, good rate capability, as well as excellent cycling stability. Electrochemical measurements show that the FeS_2/rGO composite had a high initial discharge capacity of 1263.2 mAh gg^(-1) at 100 mA gg^(-1) and a high discharge capacity of 344 mAh gg^(-1) at 10 A gg^(-1), demonstrating superior rate performance. After 100 cycles at 100 mA gg^(-1),the discharge capacity remained at 609.5 mAh g^(-1), indicating the excellent cycling stability of the FeS_2/rGO electrode.
基金This work was financially supported by the Natural Science Foundation of Shandong Province(No.ZR2019MEE106)the Science and Technology Development Plans of Shandong Province(No.2013GSF11606)the Public Special Scientific Research of the Ministry of Water Resource(No.201401024)
文摘Anti-filtration recharge wells are commonly installed in river channels and irrigation canals on the Shandong Peninsula,China,and can be used as an important recharge facility for underground reservoirs.However,during recharge,as the running time increases,the recharge capacity gradually decreases.This study was undertaken to develop a new recharge well and mitigate this deficiency.A round empty core infiltration and antifiltration recharge well and laboratory recharge test equipment were developed.Subsequently,1:25 models of the recharge pond,a round empty core recharge wellhead,and an artificial recharge well were prepared.Using equal recharge levels and ambient groundwater levels,laboratory steady-flow recharge tests on the existing anti-filtration recharge well,the new round empty core infiltration and anti-filtration recharge well,and an artificial recharge well were carried out.Experimental data on the measured groundwater table and single-well recharge quantity were also collected and analyzed.The results showed that compared with the existing anti-filtration recharge well,the new round empty core infiltration and anti-filtration recharge well had stronger anti-deposition and anti-scouring properties,and the single-well recharge quantity increased by 403%.With an increase in the number of recharge tests,the single-well recharge quantity gradually decreased and tended to stabilize as a whole.
