Integrating selective organic synthesis with hydrogen(H_(2))evolution in one photocatalytic redox reaction system sheds light on the underlying approach for concurrent employment of photogenerated electrons and holes ...Integrating selective organic synthesis with hydrogen(H_(2))evolution in one photocatalytic redox reaction system sheds light on the underlying approach for concurrent employment of photogenerated electrons and holes towards efficient production of solar fuels and chemicals.In this work,a facile one‐pot oil bath method has been proposed to fabricate a noble metal‐free ultrathin Ni‐doped ZnIn_(2)S_(4)(ZIS/Ni)composite nanosheet for effective solar‐driven selective dehydrocoupling of benzyl alcohol into value‐added C–C coupled hydrobenzoin and H_(2) fuel,which exhibits higher performance than pure ZIS nanosheet.The remarkably improved photoredox activity of ZIS/Ni is mainly attributed to the optimized electron structure featuring narrower band gap and suitable energy band position,which facilitates the ability of light harvesting and photoexcited charge carrier separation and transfer.Furthermore,it has been demonstrated that it is feasible to employ ZIS/Ni for various aromatic alcohols dehydrocoupling to the corresponding C–C coupled products.It is expected that this work can stimulate further interest on the establishment of innovative photocatalytic redox platform coupling clean solar fuels synthesis and selective organic conversion in a sustainable manner.展开更多
The development of e cient earth-abundant electrocatalysts for oxygen reduction, oxygen evolution, and hydrogen evolution reactions(ORR, OER, and HER) is important for future energy conversion and energy storage devic...The development of e cient earth-abundant electrocatalysts for oxygen reduction, oxygen evolution, and hydrogen evolution reactions(ORR, OER, and HER) is important for future energy conversion and energy storage devices, for which both rechargeable Zn–air batteries and water splitting have raised great expectations. Herein, we report a single-phase bimetallic nickel cobalt sulfide((Ni,Co)S_2) as an e cient electrocatalyst for both OER and ORR. Owing to the synergistic combination of Ni and Co, the(Ni,Co)S_2 exhibits superior electrocatalytic performance for ORR, OER, and HER in an alkaline electrolyte, and the first principle calculation results indicate that the reaction of an adsorbed O atom with a H_2O molecule to form a *OOH is the potential limiting step in the OER. Importantly, it could be utilized as an advanced air electrode material in Zn–air batteries, which shows an enhanced charge–discharge performance(charging voltage of 1.71 V and discharge voltage of 1.26 V at 2 mA cm^(-2)), large specific capacity(842 mAh g_(Zn)^(-1) at 5 mA cm^(-2)), and excellent cycling stability(480 h). Interestingly, the(Ni,Co)S_2-based Zn–air battery can e ciently power an electrochemical water-splitting unit with(Ni,Co)S_2 serving as both the electrodes. This reveals that the prepared(Ni,Co)S_2 has promising applications in future energy conversion and energy storage devices.展开更多
Structure manipulation of photocatalysts at an atomic scale is a promising way to improve its photocatalytic performance.Herein,we realize the anchoring of single Ni atoms on the ZnIn_(2)S_(4) nanosheets with rich sul...Structure manipulation of photocatalysts at an atomic scale is a promising way to improve its photocatalytic performance.Herein,we realize the anchoring of single Ni atoms on the ZnIn_(2)S_(4) nanosheets with rich sulfur vacancies.Experimental results demonstrate that single Ni atoms induce the formation of NiO-M(Zn/In) atomic interface,which can efficiently promote the carriers separation and prolong the carrier life time.In addition,in situ electron spin resonance spectroscopy(ESR) confirms that the single Ni atoms act as an electron trapping center for protons reduction.As a result,the single Ni atoms decorated ZnIn_(2)S_(4) nanosheets with rich sulfur vacancies(Ni/ZnIn_(2)S_(4)-RVs) shows a hydrogen evolution rate up to 89.4 μmol h^(-1), almost 5.7 and 2.3 times higher compared to that of ZnIn_(2)S_(4) nanosheets with poor sulfur vacancies and rich sulfur vacancies(denoted as ZnIn_(2)S_(4)-PVs and ZnIn_(2)S_(4)-RVs).This work opens up a new perspective manipulating the single-atom cocatalyst and sulfur vacancy on sulfide supports for improving photocatalytic hydrogen evolution.展开更多
文摘Integrating selective organic synthesis with hydrogen(H_(2))evolution in one photocatalytic redox reaction system sheds light on the underlying approach for concurrent employment of photogenerated electrons and holes towards efficient production of solar fuels and chemicals.In this work,a facile one‐pot oil bath method has been proposed to fabricate a noble metal‐free ultrathin Ni‐doped ZnIn_(2)S_(4)(ZIS/Ni)composite nanosheet for effective solar‐driven selective dehydrocoupling of benzyl alcohol into value‐added C–C coupled hydrobenzoin and H_(2) fuel,which exhibits higher performance than pure ZIS nanosheet.The remarkably improved photoredox activity of ZIS/Ni is mainly attributed to the optimized electron structure featuring narrower band gap and suitable energy band position,which facilitates the ability of light harvesting and photoexcited charge carrier separation and transfer.Furthermore,it has been demonstrated that it is feasible to employ ZIS/Ni for various aromatic alcohols dehydrocoupling to the corresponding C–C coupled products.It is expected that this work can stimulate further interest on the establishment of innovative photocatalytic redox platform coupling clean solar fuels synthesis and selective organic conversion in a sustainable manner.
基金supported by the National Natural Science Foundation of China (Grant Nos. 11474137 and 11674143)Program for Changjiang Scholars and Innovative Research Team in University (IRT 16R35)+1 种基金the Fundamental Research Funds for the Central Universities (Grant Nos. LZUMMM2018017, lzujbky-2018-121)the support of Ministry of Education (MOE2016-T2-2-138,Singapore),for research conducted at the National University of Singapore
文摘The development of e cient earth-abundant electrocatalysts for oxygen reduction, oxygen evolution, and hydrogen evolution reactions(ORR, OER, and HER) is important for future energy conversion and energy storage devices, for which both rechargeable Zn–air batteries and water splitting have raised great expectations. Herein, we report a single-phase bimetallic nickel cobalt sulfide((Ni,Co)S_2) as an e cient electrocatalyst for both OER and ORR. Owing to the synergistic combination of Ni and Co, the(Ni,Co)S_2 exhibits superior electrocatalytic performance for ORR, OER, and HER in an alkaline electrolyte, and the first principle calculation results indicate that the reaction of an adsorbed O atom with a H_2O molecule to form a *OOH is the potential limiting step in the OER. Importantly, it could be utilized as an advanced air electrode material in Zn–air batteries, which shows an enhanced charge–discharge performance(charging voltage of 1.71 V and discharge voltage of 1.26 V at 2 mA cm^(-2)), large specific capacity(842 mAh g_(Zn)^(-1) at 5 mA cm^(-2)), and excellent cycling stability(480 h). Interestingly, the(Ni,Co)S_2-based Zn–air battery can e ciently power an electrochemical water-splitting unit with(Ni,Co)S_2 serving as both the electrodes. This reveals that the prepared(Ni,Co)S_2 has promising applications in future energy conversion and energy storage devices.
基金the support of the National Natural Science Foundation of China(51702087,21673066)the Project funded by the China Postdoctoral Science Foundation(2019M652516)。
文摘Structure manipulation of photocatalysts at an atomic scale is a promising way to improve its photocatalytic performance.Herein,we realize the anchoring of single Ni atoms on the ZnIn_(2)S_(4) nanosheets with rich sulfur vacancies.Experimental results demonstrate that single Ni atoms induce the formation of NiO-M(Zn/In) atomic interface,which can efficiently promote the carriers separation and prolong the carrier life time.In addition,in situ electron spin resonance spectroscopy(ESR) confirms that the single Ni atoms act as an electron trapping center for protons reduction.As a result,the single Ni atoms decorated ZnIn_(2)S_(4) nanosheets with rich sulfur vacancies(Ni/ZnIn_(2)S_(4)-RVs) shows a hydrogen evolution rate up to 89.4 μmol h^(-1), almost 5.7 and 2.3 times higher compared to that of ZnIn_(2)S_(4) nanosheets with poor sulfur vacancies and rich sulfur vacancies(denoted as ZnIn_(2)S_(4)-PVs and ZnIn_(2)S_(4)-RVs).This work opens up a new perspective manipulating the single-atom cocatalyst and sulfur vacancy on sulfide supports for improving photocatalytic hydrogen evolution.
