Metallogels of an amphiphilic L-histidine derivative(LHC18)with various transition metal ions were investigated.It was found that while the amphiphile formed precipitates in aqueous solution when mixed with Cu^(2+),Zn...Metallogels of an amphiphilic L-histidine derivative(LHC18)with various transition metal ions were investigated.It was found that while the amphiphile formed precipitates in aqueous solution when mixed with Cu^(2+),Zn^(2+),Ni^(2+),it formed a hydrogel with Fe^(3+).Interestingly,upon cooling the transparent solution of LHC18 with Fe^(3+)to room temperature gently without any interruption,the gel was formed.Upon further resting at room temperature,the gel underwent shrinkage and 90% of ferric water was expelled from the gel.On the other hand,if the as-formed gel was shaken or shear forces were applied,the gel would collapse into sol.The collapsed sol will recover to become the gel within one minute upon resting and the process can be repeated many times.In addition,once the gel experiences the thixotropic process,it will not shrink anymore.So far,various metallogels have been reported,and we show the first example of a metallogel that shows dual shrinkage and self-healing properties.展开更多
基金support of this work by the Basic Research Development Program(2013CB834504)the National Natural Science Foundation of China(no.91027042,21321063 and 21474118)+1 种基金the“Strategic Priority Research Program”of the Chinese Academy of Sciences(XDB12020200)the Fund of the Chinese Academy of Sciences.
文摘Metallogels of an amphiphilic L-histidine derivative(LHC18)with various transition metal ions were investigated.It was found that while the amphiphile formed precipitates in aqueous solution when mixed with Cu^(2+),Zn^(2+),Ni^(2+),it formed a hydrogel with Fe^(3+).Interestingly,upon cooling the transparent solution of LHC18 with Fe^(3+)to room temperature gently without any interruption,the gel was formed.Upon further resting at room temperature,the gel underwent shrinkage and 90% of ferric water was expelled from the gel.On the other hand,if the as-formed gel was shaken or shear forces were applied,the gel would collapse into sol.The collapsed sol will recover to become the gel within one minute upon resting and the process can be repeated many times.In addition,once the gel experiences the thixotropic process,it will not shrink anymore.So far,various metallogels have been reported,and we show the first example of a metallogel that shows dual shrinkage and self-healing properties.
