Charge separation is generally considered as the most critical step to achieve efficient photocatalytic reactions. Although charge separation can be promoted by a semiconductor heterojunction, its efficacy is inherent...Charge separation is generally considered as the most critical step to achieve efficient photocatalytic reactions. Although charge separation can be promoted by a semiconductor heterojunction, its efficacy is inherently restrained by the mismatched atomic arrangements across the heterojunction interfaces. Here, Ta3N5–LaTaON2 heterojunction with matched interfaces has been fabricated by one-step ammonolysis treatment of KLaTa2O7. The match interfaces are formed by nearly perfect adhesion of Ta3N5 (010) and LaTaON2 (101¯) facets whose interatomic distance is similar. Compared with conventional heterojunction, the so-formed Ta3N5–LaTaON2 heterojunction are extremely efficient in accelerating charge separation which in turn enables a high photocatalytic activity. An apparent quantum efficiency as high as 11.6% at 420 ± 20 nm has been reached by Ta_(3)N_(5)–LaTaON_(2) heterojunction, which is almost three times higher than Ta_(3)N_(5)-LaTaON_(2) mixtures. These results signify the importance of matched heterojunction interfaces for charge separation and provide a paradigm in the design of efficient heterojunction-based semiconductor photocatalysts.展开更多
Two-dimensional(2D)ternary chalcogenides have attracted great attentions because of their novel chemical and physical properties arising from the synergistic effect and stoichiometric variation with the additional thi...Two-dimensional(2D)ternary chalcogenides have attracted great attentions because of their novel chemical and physical properties arising from the synergistic effect and stoichiometric variation with the additional third element compared with their binary counterparts.Here,high-quality 2D tantalum nickel selenide(Ta_(2)NiSe_(5))nanosheets are successfully fabricated by a liquid-phase exfoliation(LPE)method.The ultrafast excited carrier relaxation time and nonlinear optical absorption response are investigated and reveal that the prepared 2D Ta_(2)NiSe_(5)nanosheets have excellent broadband saturable absorption properties,which are further illustrated by three passively Q-switched(PQS)allsolid-state lasers operating at 1.0,2.0 and 2.8μm with the Ta_(2)NiSe_(5)nanosheet-based saturable absorber(SA).Furthermore,mode-locked laser operation with the pulse width as short as 356 fs is also realized at 1.0μm.This work not only demonstrates the excellent nonlinear optical proprieties and optical modulation performance of Ta_(2)NiSe_(5),but also paves the way for exploring the photonic and optoelectronic proprieties of ternary chalcogenide materials.展开更多
基金supported by the National Natural Science Foundation of China(11904108)the“Pearl River Talent Recruitment Program”(2019ZT08X639)Guangdong Basic and Applied Basic Research Foundation(2024A1515030107).
基金supported by the National Natural Science Foundation of China (62175040, 61805044, 12064027, and 62065014)the Science and Technology Program of Guangzhou(202201010242)+3 种基金Guangdong Basic and Applied Basic Research Foundation(2022A1515110981)2022 Jiangxi Province High-level and High-skilled Leading Talent Training Project Selected (No. 63)Jiangxi Provincial Department of Education Science and Technology Key Project (GJJ2204302)Jiujiang Municipal Science and Technology Program (Natural Science Foundation, Innovative Talents)(2022-2023)。
基金financially supported by the National Natural Science Foundation of China(Nos.51972233,52172225)Science and Technology Commission of Shanghai Municipality(No.19DZ2271500)the Fundamental Research Funds for the Central Universities.
文摘Charge separation is generally considered as the most critical step to achieve efficient photocatalytic reactions. Although charge separation can be promoted by a semiconductor heterojunction, its efficacy is inherently restrained by the mismatched atomic arrangements across the heterojunction interfaces. Here, Ta3N5–LaTaON2 heterojunction with matched interfaces has been fabricated by one-step ammonolysis treatment of KLaTa2O7. The match interfaces are formed by nearly perfect adhesion of Ta3N5 (010) and LaTaON2 (101¯) facets whose interatomic distance is similar. Compared with conventional heterojunction, the so-formed Ta3N5–LaTaON2 heterojunction are extremely efficient in accelerating charge separation which in turn enables a high photocatalytic activity. An apparent quantum efficiency as high as 11.6% at 420 ± 20 nm has been reached by Ta_(3)N_(5)–LaTaON_(2) heterojunction, which is almost three times higher than Ta_(3)N_(5)-LaTaON_(2) mixtures. These results signify the importance of matched heterojunction interfaces for charge separation and provide a paradigm in the design of efficient heterojunction-based semiconductor photocatalysts.
基金financially supported by the National Natural Science Foundation of China (61975095, 61675116, and 61575110)the Young Scholars Program of Shandong University (2017WLJH48)+3 种基金the Youth Cross Innovation Group of Shandong University (2020QNQT)the Key Research and Development Program of Shandong Province (2019JZZY020206)Shenzhen Science and Technology Research and Development Funds (JCYJ20180305163932273)the Program of State Key Laboratory of Quantum Optics and Quantum Optics Devices (KF201908)
文摘Two-dimensional(2D)ternary chalcogenides have attracted great attentions because of their novel chemical and physical properties arising from the synergistic effect and stoichiometric variation with the additional third element compared with their binary counterparts.Here,high-quality 2D tantalum nickel selenide(Ta_(2)NiSe_(5))nanosheets are successfully fabricated by a liquid-phase exfoliation(LPE)method.The ultrafast excited carrier relaxation time and nonlinear optical absorption response are investigated and reveal that the prepared 2D Ta_(2)NiSe_(5)nanosheets have excellent broadband saturable absorption properties,which are further illustrated by three passively Q-switched(PQS)allsolid-state lasers operating at 1.0,2.0 and 2.8μm with the Ta_(2)NiSe_(5)nanosheet-based saturable absorber(SA).Furthermore,mode-locked laser operation with the pulse width as short as 356 fs is also realized at 1.0μm.This work not only demonstrates the excellent nonlinear optical proprieties and optical modulation performance of Ta_(2)NiSe_(5),but also paves the way for exploring the photonic and optoelectronic proprieties of ternary chalcogenide materials.
