Vigorous mesoscale eddies and significant sea surface temperature(SST)variations are found in the northern edge of the Pacific warm pool that features large SST gradient.However,the relations between SST gradient,eddi...Vigorous mesoscale eddies and significant sea surface temperature(SST)variations are found in the northern edge of the Pacific warm pool that features large SST gradient.However,the relations between SST gradient,eddies,and SST variations in this region remain unexplored.In this study,by combining multi-altimeter sea surface height(SSH),satellite microwave SST observations and a mesoscale eddy dataset,we investigated the two-dimensional structures of SSTa(SST anomalies)in two subareas,which have different eddy characteristics and can be discriminated in the intensity of background SST gradient.The eddy characteristics of this region,focusing on their concentration to 21°N,are also described.We found that eddies can result in two distinct patterns of eddy-induced SST anomalies,with two different horizontal processes respectively.One is a monopole pattern that is caused by elevation/depression of the isopycnals,and another is a dipole pattern caused by eddy's rotation and stirring of the background SST field.In addition,contributions of both parts to the total SSTa and the SSTa variations were evaluated.The intensity of surrounding SST gradient plays an important role in shaping the SSTa structure:when SST gradient is larger,the eddy-associated SSTa pattern organizes more dipole.The distinct annual cycle in two components of SSTa is associated with the seasonal modulation of the warm pool's horizontal structure.展开更多
The increasing exploration of renewable and clean power sources have driven the development of highly active materials for photoelectrochemical （PEC） water splitting. However, it is still a great challenge to enhanc...The increasing exploration of renewable and clean power sources have driven the development of highly active materials for photoelectrochemical （PEC） water splitting. However, it is still a great challenge to enhance the charge utilization. Herein, we report a facile method to fabricate composite photoanode with porous BiVO4 film as the photon absorber and layered double hydroxide （LDH） nanosheet arrays as the oxygen-evolution cocatalysts （OECs）. The as-prepared BiVO4/NiFe-LDH photoanode shows an excellent performance for PEC water splitting benefitting from the synergistic effect of the superior charge separation efficiency facilitated by porous BiVO4 film and the excellent water oxidation activity resulting from LDH nanosheet arrays. A photocurrent density is 4.02 mA cm^-2 at 1.23 V vs. the reversible hydrogen electrode （RHE）. Furthermore, the O2 evolution rate at the surface of BiVO4/NiFe-LDH photoanode is as high as 29.6 μmol h^-1 cm^-2 and the high activity for water oxidation is maintained for over 30 h. Impressively, the performance of the as-fabricated composite photoanode for PEC water splitting can be further enhanced through incorporating a certain amount of Co^2＋ cation into NiFe-LDH as OEC. The photocurrent density is achieved up to 4.45 mA cm^-2 at 1.23 V vs. RHE. This value is the highest yet reported for un-doped BiVO4-based photoanodes so far.展开更多
基金Supported by the National Natural Science Foundation of China(NSFC)(Nos.41606026,41730534)the Key Research Program of Frontier Sciences,Chinese Academy of Sciences(No.QYZDB-SSW-DQC030)+2 种基金the Strategic Priority Research Program of Chinese Academy of Sciences(Nos.XDA19060102,XDA11010201)the Aoshan Talents Program by the Qingdao National Laboratory for Marine Science and Technology(Nos.2017ASTCP-ES03)the Youth Program of the NSFC and CAS(Nos.Y72143101B,Y82122101L)
文摘Vigorous mesoscale eddies and significant sea surface temperature(SST)variations are found in the northern edge of the Pacific warm pool that features large SST gradient.However,the relations between SST gradient,eddies,and SST variations in this region remain unexplored.In this study,by combining multi-altimeter sea surface height(SSH),satellite microwave SST observations and a mesoscale eddy dataset,we investigated the two-dimensional structures of SSTa(SST anomalies)in two subareas,which have different eddy characteristics and can be discriminated in the intensity of background SST gradient.The eddy characteristics of this region,focusing on their concentration to 21°N,are also described.We found that eddies can result in two distinct patterns of eddy-induced SST anomalies,with two different horizontal processes respectively.One is a monopole pattern that is caused by elevation/depression of the isopycnals,and another is a dipole pattern caused by eddy's rotation and stirring of the background SST field.In addition,contributions of both parts to the total SSTa and the SSTa variations were evaluated.The intensity of surrounding SST gradient plays an important role in shaping the SSTa structure:when SST gradient is larger,the eddy-associated SSTa pattern organizes more dipole.The distinct annual cycle in two components of SSTa is associated with the seasonal modulation of the warm pool's horizontal structure.
基金supported by the National Natural Science Foundation of China(21422104)the Key Project of Natural Science Foundation of Tianjin City(16JCZDJC30600)
文摘The increasing exploration of renewable and clean power sources have driven the development of highly active materials for photoelectrochemical （PEC） water splitting. However, it is still a great challenge to enhance the charge utilization. Herein, we report a facile method to fabricate composite photoanode with porous BiVO4 film as the photon absorber and layered double hydroxide （LDH） nanosheet arrays as the oxygen-evolution cocatalysts （OECs）. The as-prepared BiVO4/NiFe-LDH photoanode shows an excellent performance for PEC water splitting benefitting from the synergistic effect of the superior charge separation efficiency facilitated by porous BiVO4 film and the excellent water oxidation activity resulting from LDH nanosheet arrays. A photocurrent density is 4.02 mA cm^-2 at 1.23 V vs. the reversible hydrogen electrode （RHE）. Furthermore, the O2 evolution rate at the surface of BiVO4/NiFe-LDH photoanode is as high as 29.6 μmol h^-1 cm^-2 and the high activity for water oxidation is maintained for over 30 h. Impressively, the performance of the as-fabricated composite photoanode for PEC water splitting can be further enhanced through incorporating a certain amount of Co^2＋ cation into NiFe-LDH as OEC. The photocurrent density is achieved up to 4.45 mA cm^-2 at 1.23 V vs. RHE. This value is the highest yet reported for un-doped BiVO4-based photoanodes so far.
