Charge Carrier Transfer in Ta3N5 Photoanodes Prepared by Different Methods for Solar Water Splitting

2016 ◽  
Vol 69 (6) ◽  
pp. 631 ◽  
Author(s):  
Mingxue Li ◽  
Wenjun Luo ◽  
Liheng Yang ◽  
Xin Zhao ◽  
Zhigang Zou

The preparation method of a photoanode can affect its water splitting property. Here, as examples, we prepared Ta3N5 photoanodes by an electrophoresis deposition (EPD) method and an oxidation and nitridation of Ta foil (ONTF) method. The light harvest, interfacial charge transfer, and charge separation of the two Ta3N5 photoanodes were analysed to gain insight into the role of the preparation method on the water splitting property. The results suggested that the ONTF-prepared Ta3N5 showed a higher solar energy conversion efficiency, arising from its better interfacial charge transfer efficiency and higher charge separation efficiency. The higher charge separation efficiency was mainly attributed to good electron transfer, and the inter-particle connectivity was key for the electron transfer in the photoanodes. Especially, the dense, small particle structure of ONTF-prepared Ta3N5 was beneficial for increasing the connectivity between inter-particles. This comparison of preparation methods can be used as a reference for future photoanode preparation to improve the water splitting property of photoelectrochemical cells.

2021 ◽  
Vol 16 (1) ◽  
Author(s):  
Peng Cui ◽  
Yuan Xue

AbstractThe sensitive electronic environment at the quantum dot (QD)–dye interface becomes a roadblock to enhancing the energy conversion efficiency of dye-functionalized quantum dots (QDs). Energy alignments and electronic couplings are the critical factors governing the directions and rates of different charge transfer pathways at the interface, which are tunable by changing the specific linkage groups that connect a dye to the QD surface. The variation of specific anchors changes the binding configurations of a dye on the QD surface. In addition, the presence of a co-adsorbent changes the dipole–dipole and electronic interactions between a QD and a dye, resulting in different electronic environments at the interface. In the present work, we performed density functional theory (DFT)-based calculations to study the different binding configurations of N719 dye on the surface of a Cd33Se33 QD with a co-adsorbent D131 dye. The results revealed that the electronic couplings for electron transfer were greater than for hole transfer when the structure involved isocyanate groups as anchors. Such strong electronic couplings significantly stabilize the occupied states of the dye, pushing them deep inside the valence band of the QD and making hole transfer in these structures thermodynamically unfavourable. When carboxylates were involved as anchors, the electronic couplings for hole transfer were comparable to electron transfer, implying efficient charge separation at the QD–dye interface and reduced electron–hole recombination within the QD. We also found that the electronic couplings for electron transfer were larger than those for back electron transfer, suggesting efficient charge separation in photoexcited QDs. Overall, the current computational study reveals some fundamental aspects of the relationship between the interfacial charge transfer for QD@dye composites and their morphologies which benefit the design of QD-based nanomaterials for photovoltaic applications.


2018 ◽  
Vol 17 (9) ◽  
pp. 1153-1156 ◽  
Author(s):  
Tomomi Tatebe ◽  
Takashi Harada ◽  
Kazuhide Kamiya ◽  
Shuji Nakanishi

Photo-induced electron-transfer reactions occurring at the interface between titanium dioxide modified with hexacyanoferrate(iii) (Fe(iii)-CN-TiO2) were characterized.


Nano Letters ◽  
2019 ◽  
Vol 19 (2) ◽  
pp. 1234-1241 ◽  
Author(s):  
Guancai Xie ◽  
Liming Guan ◽  
Linjuan Zhang ◽  
Beidou Guo ◽  
Aisha Batool ◽  
...  

2018 ◽  
Vol 20 (11) ◽  
pp. 7710-7720 ◽  
Author(s):  
Iwona Grądzka ◽  
Mateusz Gierszewski ◽  
Jerzy Karolczak ◽  
Marcin Ziółek

Standard ruthenium components of dye-sensitized solar cells (sensitizer N719) and dye-sensitized photoelectrochemical cells (sensitizer RuP) are investigated to compare their photodynamics and charge separation efficiency.


Author(s):  
Umesh Prasad ◽  
James Luke Young ◽  
Justin C. Johnson ◽  
Deborah McGott ◽  
Hengfei Gu ◽  
...  

Photoanodes containing a WO3/BiVO4 heterojunction have demonstrated promising photoelectrochemical water splitting performance, but the ability to effectively passivate the WO3/BiVO4 interface has limited charge transport and collection. Here, the WO3/BiVO4...


2019 ◽  
Vol 324 ◽  
pp. 134844 ◽  
Author(s):  
Zhenzhu Xu ◽  
Shuguang Zhang ◽  
Fangliang Gao ◽  
Peng Gao ◽  
Yuefeng Yu ◽  
...  

2019 ◽  
Vol 43 (17) ◽  
pp. 6753-6764 ◽  
Author(s):  
Qiannan Li ◽  
Yuguo Xia ◽  
Kangliang Wei ◽  
Xiaotong Ding ◽  
Shun Dong ◽  
...  

Surface polarization promotes the charge separation efficiency of PCN/PANI/BTO ternary heterojunction, resulting in an enhanced visible-light photocatalytic hydrogen production activity.


Sign in / Sign up

Export Citation Format

Share Document