Ultrasmall Au nanoclusters have been proven to effectively enhance the catalytic performance of NiFe layered double hydroxides(NiFe-LDHs)toward oxygen evolution reaction(OER),yet the surface ligand effect of the Au na...Ultrasmall Au nanoclusters have been proven to effectively enhance the catalytic performance of NiFe layered double hydroxides(NiFe-LDHs)toward oxygen evolution reaction(OER),yet the surface ligand effect of the Au nanoclusters still remains elusive.Herein,a systematic study is reported to examine the OER performance of NiFe-LDHs supported atom-precise all alkynyl-protected[Au_(28)(~tBuC≡C)17]~-nanoclusters(Au_(28)-Alkynyl in short)and thiolate-protected Au_(28)(TBBT)_(20)(TBBT=4-tert-butylbenzene thiol)counterp arts(Au_(28)-Thiolate in short).The Au_(28)-Alkynyl cluster has characteristic absorbance feature,and its composition is verified by mass spectrometry.It possesses a drastically different structure from the reported mixed ligand protected Au_(28)nanoclusters.Interestingly,the NiFe-LDHs loaded with Au_(28)-Alkynyl exhibited a superior OER performance than the sample loaded with Au28-Thiolate under the same conditions,evidenced by a smaller overpotential of 205 mV at the current density of 10 mA·cm^(-2)and a lower Tafel slope value of 41.0 mV·dec^(-1)in 1 mol·L^(-1)KOH.Such excellent performance is attributed to the interfaces created between the NiFe-LDHs and the Au nanoclusters,as density functional theory calculations reveal that more significant charge transfer occurs in Au_(28)-Alkynyl/NiFeLDHs catalyst,and more importantly,the energy barrier of the potential-determining step in the OER process for Au28-Alkynyl/NiFe-LDHs is much lower than that of Au28-Thiolate/NiFe-LDHs hence favors the electrocatalytic reaction.展开更多
To the Editor:Nowadays,most infants with tetralogy of Fallot(TOF)survive the initial surgical repair;however,they continue to experience residual hemodynamic and physiologic abnormalities in the follow-up.[1]Pulmonary...To the Editor:Nowadays,most infants with tetralogy of Fallot(TOF)survive the initial surgical repair;however,they continue to experience residual hemodynamic and physiologic abnormalities in the follow-up.[1]Pulmonary regurgitation(PR)is still recognized as the most common complication that determines late outcomes.PR may result in right ventricular(RV)dilatation and,ultimately,cardiac dysfunction.Indicators of deterioration of clinical status such as impaired exercise tolerance,ventricular arrhythmia,and sudden cardiac death have all been associated with chronic PR.展开更多
基金financially supported by Guangdong Natural Science Funds (No.2022A1515011840)the Research Grant Council of Hong Kong for support through the projects (Nos.16201820 and 16206019)the Project of Hetao Shenzhen-Hong Kong Science and Technology Innovation Cooperation Zone (No.HZQB-KCZYB-2020083)。
文摘Ultrasmall Au nanoclusters have been proven to effectively enhance the catalytic performance of NiFe layered double hydroxides(NiFe-LDHs)toward oxygen evolution reaction(OER),yet the surface ligand effect of the Au nanoclusters still remains elusive.Herein,a systematic study is reported to examine the OER performance of NiFe-LDHs supported atom-precise all alkynyl-protected[Au_(28)(~tBuC≡C)17]~-nanoclusters(Au_(28)-Alkynyl in short)and thiolate-protected Au_(28)(TBBT)_(20)(TBBT=4-tert-butylbenzene thiol)counterp arts(Au_(28)-Thiolate in short).The Au_(28)-Alkynyl cluster has characteristic absorbance feature,and its composition is verified by mass spectrometry.It possesses a drastically different structure from the reported mixed ligand protected Au_(28)nanoclusters.Interestingly,the NiFe-LDHs loaded with Au_(28)-Alkynyl exhibited a superior OER performance than the sample loaded with Au28-Thiolate under the same conditions,evidenced by a smaller overpotential of 205 mV at the current density of 10 mA·cm^(-2)and a lower Tafel slope value of 41.0 mV·dec^(-1)in 1 mol·L^(-1)KOH.Such excellent performance is attributed to the interfaces created between the NiFe-LDHs and the Au nanoclusters,as density functional theory calculations reveal that more significant charge transfer occurs in Au_(28)-Alkynyl/NiFeLDHs catalyst,and more importantly,the energy barrier of the potential-determining step in the OER process for Au28-Alkynyl/NiFe-LDHs is much lower than that of Au28-Thiolate/NiFe-LDHs hence favors the electrocatalytic reaction.
文摘To the Editor:Nowadays,most infants with tetralogy of Fallot(TOF)survive the initial surgical repair;however,they continue to experience residual hemodynamic and physiologic abnormalities in the follow-up.[1]Pulmonary regurgitation(PR)is still recognized as the most common complication that determines late outcomes.PR may result in right ventricular(RV)dilatation and,ultimately,cardiac dysfunction.Indicators of deterioration of clinical status such as impaired exercise tolerance,ventricular arrhythmia,and sudden cardiac death have all been associated with chronic PR.
