Photocatalytic water splitting is an economical and sustainable pathway to use solar energy for large‐scale H2production.We report a highly efficient noble‐metal‐free photocatalyst formed by integrating amorphous N...Photocatalytic water splitting is an economical and sustainable pathway to use solar energy for large‐scale H2production.We report a highly efficient noble‐metal‐free photocatalyst formed by integrating amorphous NiS with a CdS nanorods(NRs)/ZnS heterojunction material for photocatalytic H2production in water under visible light irradiation(?>420nm).The results show that the photocatalytic H2production rate reaches an optimal value of up to574μmol·h–1after the loading of NiS,which is more than38times higher than the catalytic activity of pure CdS NRs.The average apparent quantum yield is^43.2%during5h of irradiation by monochromatic420nm light.The present study demonstrates the advantage of integration strategies to form not only semiconductor heterojunctions but also photocatalyst‐cocatalyst interfaces to enhance the catalytic activity for photocatalytic H2production.展开更多
Using internal by two-photon induced light absorption of semiconductor material to lengthen the pulses of Q-switched lasers is discussed. The rate equations are solved and the experiments are performed with a rotating...Using internal by two-photon induced light absorption of semiconductor material to lengthen the pulses of Q-switched lasers is discussed. The rate equations are solved and the experiments are performed with a rotating prism Q-switched ruby laser with a CdS sample in its cavity. As predicted by the theory,the output intensity and output energy both are decreased and pulse length is increased as compared with the normal Q-switched case.展开更多
Visible-light-initiated organic transformations have received much attention because of low cost, relative safety, and environmental friendliness. In this work, we report on a novel type of visible-light-driven photoc...Visible-light-initiated organic transformations have received much attention because of low cost, relative safety, and environmental friendliness. In this work, we report on a novel type of visible-light-driven photocatalysts, namely, porous nanocomposites of CdS-nanoparticle-decorated metal-organic frameworks （MOF）, prepared by a simple solvothermal method in which porous MIL-100（Fe） served as the support and cadmium acetate （Cd（Ac）2） as the CdS precursor. When the selective oxidation of benzyl alcohol to benzaldehyde is used as the probe reaction, the results show that the combination of MIL-100（Fe） and CdS semiconductor can remarkably enhance the photocatalytic efficiency at room temperature, as compared to that of pure CdS. The enhanced photocatalytic performance can be attributed to the combined effects of enhanced light absorption, more efficient separation of photogenerated electron-hole pairs, and increased surface area of CdS due to the presence of MIL-100（Fe）. This work demonstrates that MOF-based composite materials hold great promise for applications in the field of solar-energy conversion into chemical energy.展开更多
The response of field electron emission of cadmium sulfide (CdS) nanowires (NWs) to visible light has been investigated.It is found that,upon light illumination,the turn-on voltage drops,emission current increases obv...The response of field electron emission of cadmium sulfide (CdS) nanowires (NWs) to visible light has been investigated.It is found that,upon light illumination,the turn-on voltage drops,emission current increases obviously,and the Fowler-Nordheim behavior deviates from a straight line.A process of field emission coupled with semiconducting properties of CdS NWs is proposed.Photon-excited electron transition from the valence band to the conductance band of CdS nanowires increases the quantity of emitting electrons,and the photoemission decreases the effective work function of CdS emitters,which largely enhances the field emission performance.The response of field emission of CdS NWs to light illumination suggests an approach for tuning field emission of semiconductor emitters.展开更多
基金supported by the National Key Research and Development Program of China(2017YFA0402800)the National Natural Science Foundation of China(51772285,21473170)~~
文摘Photocatalytic water splitting is an economical and sustainable pathway to use solar energy for large‐scale H2production.We report a highly efficient noble‐metal‐free photocatalyst formed by integrating amorphous NiS with a CdS nanorods(NRs)/ZnS heterojunction material for photocatalytic H2production in water under visible light irradiation(?>420nm).The results show that the photocatalytic H2production rate reaches an optimal value of up to574μmol·h–1after the loading of NiS,which is more than38times higher than the catalytic activity of pure CdS NRs.The average apparent quantum yield is^43.2%during5h of irradiation by monochromatic420nm light.The present study demonstrates the advantage of integration strategies to form not only semiconductor heterojunctions but also photocatalyst‐cocatalyst interfaces to enhance the catalytic activity for photocatalytic H2production.
文摘Using internal by two-photon induced light absorption of semiconductor material to lengthen the pulses of Q-switched lasers is discussed. The rate equations are solved and the experiments are performed with a rotating prism Q-switched ruby laser with a CdS sample in its cavity. As predicted by the theory,the output intensity and output energy both are decreased and pulse length is increased as compared with the normal Q-switched case.
基金This work is supported by the National Natural Science Foundation of China （Grant No. U1232102）, National Basic Research Program of China （Nos. 2010CB923302 and 2013CB834605）, and the Specialized Research Fund for the Doctoral Program of Higher Education （SRFDP） of Ministry of Education （Grant No. 20113402110029）.
文摘Visible-light-initiated organic transformations have received much attention because of low cost, relative safety, and environmental friendliness. In this work, we report on a novel type of visible-light-driven photocatalysts, namely, porous nanocomposites of CdS-nanoparticle-decorated metal-organic frameworks （MOF）, prepared by a simple solvothermal method in which porous MIL-100（Fe） served as the support and cadmium acetate （Cd（Ac）2） as the CdS precursor. When the selective oxidation of benzyl alcohol to benzaldehyde is used as the probe reaction, the results show that the combination of MIL-100（Fe） and CdS semiconductor can remarkably enhance the photocatalytic efficiency at room temperature, as compared to that of pure CdS. The enhanced photocatalytic performance can be attributed to the combined effects of enhanced light absorption, more efficient separation of photogenerated electron-hole pairs, and increased surface area of CdS due to the presence of MIL-100（Fe）. This work demonstrates that MOF-based composite materials hold great promise for applications in the field of solar-energy conversion into chemical energy.
基金supported by the National Natural Science Foundation of China (Grant Nos. 60771060,61072136 and 60871081)
文摘The response of field electron emission of cadmium sulfide (CdS) nanowires (NWs) to visible light has been investigated.It is found that,upon light illumination,the turn-on voltage drops,emission current increases obviously,and the Fowler-Nordheim behavior deviates from a straight line.A process of field emission coupled with semiconducting properties of CdS NWs is proposed.Photon-excited electron transition from the valence band to the conductance band of CdS nanowires increases the quantity of emitting electrons,and the photoemission decreases the effective work function of CdS emitters,which largely enhances the field emission performance.The response of field emission of CdS NWs to light illumination suggests an approach for tuning field emission of semiconductor emitters.
