摘要
The emerging Weyl semi-metals with robust topological surface states are
very promising candidates to rationally develop new-generation electrocatalysts for dye-sensitized solar cells (DSSCs). In this study, a chemical vapor
deposition (CVD) method to synthesize highly crystalline Weyl semi-metallic
Mo xW1-xTe2 nanocrystals, which are applied for the counter electrode (CE) of
DSSCs for the first time, are employed. By controlling the temperaturedependent phase-engineered synthesis, the nanocrystal grown at 760 - C exhibits the mixed phases of semiconducting Td- & 2H-Mo0.32W0.67Te2.01 with charge carrier density of (1.20 0.02) 1019 cm3; whereas, the nanocrystal synthesized at 820 C shows a single phase of semi-metallic TdMo0.29W0.72Te1.99 with much higher carrier density of (1.59 0.04) 1020 cm3. In the cyclic voltammetry (CV) analysis over 200 cycles, the MoxW1-xTe2-based electrodes show better stability in the I/I3 electrolyte than a Pt electrode. In DSSC tests, a Td-Mo0.29W0.72Te1.99-decorated CE achieves the efficiency (η) of 8.85%, better than those CEs fabricated with Td- & 2HMo0.32W0.67Te2.01 (7.81%) and sputtered Pt (8.01%). The electrochemical impedance spectra reveal that the Td-Mo0.29W0.72Te1.99 electrode possesses low charge-transfer resistance in electrocatalytic reactions. These exceptional properties make Weyl semi-metallic Td-MoxW1-xTe2 a potential electrode material for a wide variety of electrocatalytic applications.
very promising candidates to rationally develop new-generation electrocatalysts for dye-sensitized solar cells (DSSCs). In this study, a chemical vapor
deposition (CVD) method to synthesize highly crystalline Weyl semi-metallic
Mo xW1-xTe2 nanocrystals, which are applied for the counter electrode (CE) of
DSSCs for the first time, are employed. By controlling the temperaturedependent phase-engineered synthesis, the nanocrystal grown at 760 - C exhibits the mixed phases of semiconducting Td- & 2H-Mo0.32W0.67Te2.01 with charge carrier density of (1.20 0.02) 1019 cm3; whereas, the nanocrystal synthesized at 820 C shows a single phase of semi-metallic TdMo0.29W0.72Te1.99 with much higher carrier density of (1.59 0.04) 1020 cm3. In the cyclic voltammetry (CV) analysis over 200 cycles, the MoxW1-xTe2-based electrodes show better stability in the I/I3 electrolyte than a Pt electrode. In DSSC tests, a Td-Mo0.29W0.72Te1.99-decorated CE achieves the efficiency (η) of 8.85%, better than those CEs fabricated with Td- & 2HMo0.32W0.67Te2.01 (7.81%) and sputtered Pt (8.01%). The electrochemical impedance spectra reveal that the Td-Mo0.29W0.72Te1.99 electrode possesses low charge-transfer resistance in electrocatalytic reactions. These exceptional properties make Weyl semi-metallic Td-MoxW1-xTe2 a potential electrode material for a wide variety of electrocatalytic applications.
| 原文 | American English |
|---|---|
| 文章編號 | 1800314 |
| 期刊 | Solar RRL |
| 卷 | 3 |
| 出版狀態 | Published - 2019 |