Peanut-chocolate-ball-inspired construction of the interface engineering between CdS and intergrown Cd:Boosting both the photocatalytic activity and photocorrosion resistance

Interface engineering can improve the charge separation efficiency and inhibit photocorrosion is an emerging direction of developing more efficient and cost-effective photocatalytic systems.Herein,we report the sulfur-confined intimate Cd S intergrown Cd(Cd S/Cd)Ohmic junction(peanut-chocolate-ball like)for high-efficient H2production with superior anti-photocorrosion ability,which was fabricated from in-situ photoreduction of CdS intergrown Cd2SO4(OH)2(CdS/Cd2SO4(OH)2)prepared through a facile space-controlled-solvothermal method.The ratios of CdS/Cd can be effectively controlled by tunning that of CdS/Cd2SO4(OH)2which were prepared by adjusting the volume of reaction liquid and the remaining space of the reactor.Experiments investigations and density functional theory(DFT)calculations reveal that the Cd S intergrown Cd Ohmic junction interfaces(with appropriate content Cd intergrown on Cd S(19.54 wt%))are beneficial in facilitating the transfer of photogenerated electrons by constructing an interfacial electric field and forming sulfur-confined structures for preventing the positive holes(h+)oxidize the Cd S.This contributes to a high photocatalytic H2production activity of 95.40μmol h-1(about 32.3 times higher than bare Cd S)and possesses outstanding photocatalytic stability over 205 h,much longer than most Cd S-based photocatalysts previously reported.The interface engineering design inspired by the structure of peanut-chocolate-ball can greatly promote the future development of catalytic systems for wider application.

Tripotassium citrate monohydrate derived carbon nanosheets as a competent assistant to manganese dioxide with remarkable performance in the supercapacitor

Production cost,capacitance,and electrode materials safety are the key factors to be concerned about for supercapacitors.In this work,a type of carbon nanosheets was produced through the carbonization of tripotassium citrate monohydrate and nitric acidification.Subsequently,a well-designed manganese dioxide/carbon nanosheets composite was synthesized through hydrothermal treating.The carbon nanosheets served as the substrate for growing the manganese dioxide,regulating its distribution,and preventing it from inhomogeneous dimensions and severe agglomeration.Many manganese dioxide nanosheets grew vertically on the numerous functional groups generated on the surface of the carbon nanosheets during acidification.The synergistic combination of carbon nanosheets and manganese dioxide tailors the electrochemical performance of the composite,which benefits from the excellent conductivity and stability of carbon nanosheets.The carbon nanosheets derived from tripotassium citrate monohydrate are conducive to the remarkable performance of manganese dioxide/carbon nanosheets electrode.Finally,an asymmetric supercapacitor with active carbon as the cathode and manganese dioxide/carbon nanosheets as the anode was assembled,achieving an outstanding energy density of 54.68 Wh·kg^(−1) and remarkable power density of 6399.2 W·kg^(−1) superior to conventional lead-acid batteries.After 10000 charge-discharge cycles,the device retained 75.3%of the initial capacitance,showing good cycle stability.Two assembled asymmetric supercapacitors in series charged for 3 min could power a yellow light emitting diode with an operating voltage of 2 V for 2 min.This study may provide valuable insights for applying carbon materials and manganese dioxide in the energy storage field.