Photoelectrochemical(PEC)water-splitting using solar energy holds great promise for the renewable energy future,and a key challenge in the development of industry viable PEC devices is the unavailability of high-effic...Photoelectrochemical(PEC)water-splitting using solar energy holds great promise for the renewable energy future,and a key challenge in the development of industry viable PEC devices is the unavailability of high-efficient photoanodes.Herein,we designed a TiO_(2) model photocatalyst with nano-groove pattern and different surface orientation using low-energy Ar+irradiation and photoetching of TiO_(2),and significantly improved the intrinsic activity for PEC water oxidation.High-resolution transmission electron microscopy directly manifests that the grooves consist of highly stepped surface with<110>steps and well-crystallized.Transient absorption spectroscopy reveals the groove surface that allows for increased recovery lifetime,which ensures promoted electron-hole separation efficiency.Surface photovoltage directly shows the carrier separation and transportation behaviors,verified by selective photodeposition,demonstrating the groove surface on TiO_(2) contributes to electron-hole separation.This work proposes an efficient and scalable photoanode strategy,which potentially can open new opportunities for achieving efficient PEC water oxidation performance.展开更多
本文报道了一种在蓝宝石衬底上NaOH辅助化学气相沉积(CVD)生长有序排列单层MoS2条带的方法.MoS2条带具有优良的单晶性,其载流子迁移率为~150 cm^2V^-1s^-1,在550 nm波长下的光学响应为103 mA W^-1.单层MoS2条带在蓝宝石衬底上具有两种...本文报道了一种在蓝宝石衬底上NaOH辅助化学气相沉积(CVD)生长有序排列单层MoS2条带的方法.MoS2条带具有优良的单晶性,其载流子迁移率为~150 cm^2V^-1s^-1,在550 nm波长下的光学响应为103 mA W^-1.单层MoS2条带在蓝宝石衬底上具有两种生长方式,其中一种为受层间范德华力以及晶格影响的取向生长,另一种为受蓝宝石台阶约束的平行生长.NaOH的引入量对MoS2形态与取向起重要作用,可以实现从取向性三角形晶畴,受衬底晶格影响的取向MoS2条带,受衬底台阶约束的平行条带,再到大尺寸杂乱取向三角形晶畴的连续可调.本文的结果有利于推动MoS2的基础研究及器件应用,也为合成其他一维和二维纳米结构开辟了新途径.展开更多
基金support from the Ministry of Science and Technology of China (No. 2016YFA0202803 and 2018YFA0704503)the National Natural Science Foundation of China (21991152,21991150, 21802096, 21832004, 21902179 and 22072093)+2 种基金the Shanghai-XFEL Beamline Project (SBP) (no. 31011505505885920161A2101001)supported by ME2 project under contract No.11227902 from National Natural Science Foundation of Chinasupport of Shanghai Sailing Program (No. 19YF1455600)。
文摘Photoelectrochemical(PEC)water-splitting using solar energy holds great promise for the renewable energy future,and a key challenge in the development of industry viable PEC devices is the unavailability of high-efficient photoanodes.Herein,we designed a TiO_(2) model photocatalyst with nano-groove pattern and different surface orientation using low-energy Ar+irradiation and photoetching of TiO_(2),and significantly improved the intrinsic activity for PEC water oxidation.High-resolution transmission electron microscopy directly manifests that the grooves consist of highly stepped surface with<110>steps and well-crystallized.Transient absorption spectroscopy reveals the groove surface that allows for increased recovery lifetime,which ensures promoted electron-hole separation efficiency.Surface photovoltage directly shows the carrier separation and transportation behaviors,verified by selective photodeposition,demonstrating the groove surface on TiO_(2) contributes to electron-hole separation.This work proposes an efficient and scalable photoanode strategy,which potentially can open new opportunities for achieving efficient PEC water oxidation performance.
基金This work was financially supported by the Science and Technology Commission of Shanghai Municipality(18511110700).
文摘本文报道了一种在蓝宝石衬底上NaOH辅助化学气相沉积(CVD)生长有序排列单层MoS2条带的方法.MoS2条带具有优良的单晶性,其载流子迁移率为~150 cm^2V^-1s^-1,在550 nm波长下的光学响应为103 mA W^-1.单层MoS2条带在蓝宝石衬底上具有两种生长方式,其中一种为受层间范德华力以及晶格影响的取向生长,另一种为受蓝宝石台阶约束的平行生长.NaOH的引入量对MoS2形态与取向起重要作用,可以实现从取向性三角形晶畴,受衬底晶格影响的取向MoS2条带,受衬底台阶约束的平行条带,再到大尺寸杂乱取向三角形晶畴的连续可调.本文的结果有利于推动MoS2的基础研究及器件应用,也为合成其他一维和二维纳米结构开辟了新途径.
