High-performance and stable electrocatalysts are vital for the oxygen evolution reaction(OER).Herein,via a one-pot hydrothermal method,Ni/Fe/V ternary layered double hydroxides(NiFeV-LDH)derived from Ni foam are fabri...High-performance and stable electrocatalysts are vital for the oxygen evolution reaction(OER).Herein,via a one-pot hydrothermal method,Ni/Fe/V ternary layered double hydroxides(NiFeV-LDH)derived from Ni foam are fabricated to work as highly active and durable electrocatalysts for OER.By changing the feeding ratio of Fe and V salts,the prepared ternary hydroxides were optimized.At an Fe:V ratio of 0.5:0.5,NiFeV-LDH exhibits outstanding OER activity superior to that of the binary hydroxides,requiring overpotentials of 269 and 274 mV at 50 mA·cm^(−2)in the linear sweep voltammetry and sampled current voltammetry measurements,respectively.Importantly,NiFeV-LDH shows extraordinary long-term stability(≥75 h)at an extremely high current density of 200 mA·cm^(−2).In contrast,the binary hydroxides present quick decay at 200 mA·cm^(−2)or even reduced current densities(150 and 100 mA·cm^(−2)).The outstanding OER performance of NiFeV-LDH benefits from the synergistic effect of V and Fe while doping the third metal into bimetallic hydroxide layers:(a)Fe plays a crucial role as the active site;(b)electron-withdrawing V stabilizes the high valence state of Fe,thus accelerating the OER process;(c)V further offers great stabilization for the formed intermediate of FeOOH,thus achieving superior durability.展开更多
Chemodynamic therapy (CDT) has attracted tremendous interest in cancer therapy because it is independent of oxygen and photoirradiation. However, the therapeutic efficacy of CDT is restricted by insufficient H_(2)O_(2...Chemodynamic therapy (CDT) has attracted tremendous interest in cancer therapy because it is independent of oxygen and photoirradiation. However, the therapeutic efficacy of CDT is restricted by insufficient H_(2)O_(2) levels in tumor cells. Herein, employing endogenous GSH as a template and cationic polymeric chitosan (CS) as crosslinker and stabilizer exhibiting easy cell uptake, red luminescent gold nanoclusters (denoted CS-GSH@AuNCs) were successfully synthesized in HeLa cells. The in situ synthesized CS-GSH@AuNCs exhibited both superoxidase dismutase (SOD) and peroxidase (POD)-like activity, which could promote the production of H_(2)O_(2) from superoxide anion radicals (O_(2)^(·-)) and then ^(·)OH. The combination of GSH elimination and H_(2)O_(2) elevation boosted the generation of ^(·)OH, which could trigger cancer cell apoptosis and death. The enzyme-like activity of CS-GSH@AuNCs could be effectively activated under acidic conditions, and showed a high killing effect on tumor cells but minimal toxicity to normal cells. The developed GSH consumption and ^(·)OH promotion theranostic platform is an innovative route for enhanced CDT by the amplification of oxidative stress.展开更多
基金supported by the National Natural Science Foundation of China(Grant Nos.22176017 and 21871028)CAS“Light of West China Program”(Grant No.XAB2020YW16)+1 种基金Scientific Research Project of the Ningxia Higher Education Department of China(Grant No.NGY2020034)Foundation of State Key Laboratory of Highefficiency Utilization of Coal and Green Chemical Engineering(Grant No.2020-KF-40).
文摘High-performance and stable electrocatalysts are vital for the oxygen evolution reaction(OER).Herein,via a one-pot hydrothermal method,Ni/Fe/V ternary layered double hydroxides(NiFeV-LDH)derived from Ni foam are fabricated to work as highly active and durable electrocatalysts for OER.By changing the feeding ratio of Fe and V salts,the prepared ternary hydroxides were optimized.At an Fe:V ratio of 0.5:0.5,NiFeV-LDH exhibits outstanding OER activity superior to that of the binary hydroxides,requiring overpotentials of 269 and 274 mV at 50 mA·cm^(−2)in the linear sweep voltammetry and sampled current voltammetry measurements,respectively.Importantly,NiFeV-LDH shows extraordinary long-term stability(≥75 h)at an extremely high current density of 200 mA·cm^(−2).In contrast,the binary hydroxides present quick decay at 200 mA·cm^(−2)or even reduced current densities(150 and 100 mA·cm^(−2)).The outstanding OER performance of NiFeV-LDH benefits from the synergistic effect of V and Fe while doping the third metal into bimetallic hydroxide layers:(a)Fe plays a crucial role as the active site;(b)electron-withdrawing V stabilizes the high valence state of Fe,thus accelerating the OER process;(c)V further offers great stabilization for the formed intermediate of FeOOH,thus achieving superior durability.
基金supported by the National Natural Science Foundation of China (No. 22074007)。
文摘Chemodynamic therapy (CDT) has attracted tremendous interest in cancer therapy because it is independent of oxygen and photoirradiation. However, the therapeutic efficacy of CDT is restricted by insufficient H_(2)O_(2) levels in tumor cells. Herein, employing endogenous GSH as a template and cationic polymeric chitosan (CS) as crosslinker and stabilizer exhibiting easy cell uptake, red luminescent gold nanoclusters (denoted CS-GSH@AuNCs) were successfully synthesized in HeLa cells. The in situ synthesized CS-GSH@AuNCs exhibited both superoxidase dismutase (SOD) and peroxidase (POD)-like activity, which could promote the production of H_(2)O_(2) from superoxide anion radicals (O_(2)^(·-)) and then ^(·)OH. The combination of GSH elimination and H_(2)O_(2) elevation boosted the generation of ^(·)OH, which could trigger cancer cell apoptosis and death. The enzyme-like activity of CS-GSH@AuNCs could be effectively activated under acidic conditions, and showed a high killing effect on tumor cells but minimal toxicity to normal cells. The developed GSH consumption and ^(·)OH promotion theranostic platform is an innovative route for enhanced CDT by the amplification of oxidative stress.
