Shuangchao Zhao

Bio: Shuangchao Zhao is an academic researcher from Dalian University of Technology. The author has contributed to research in topics: Heterojunction & Carbon nitride. The author has an hindex of 1, co-authored 2 publications receiving 5 citations.

Facile Construction of a Hollow In2S3/Polymeric Carbon Nitride Heterojunction for Efficient Visible-Light-Driven CO2 Reduction

Abstract: The development of high-efficiency photocatalysts is of great importance to realize robust solar-driven CO₂ conversion; however, the low carrier separation efficiency and poor light absorption ability usually limit the performance of the photocatalysts. Herein, a hollow In₂S₃/polymeric carbon nitride (IS/CN) heterojunction was prepared via electrostatic self-assembly and in situ sulfidation under solvothermal conditions. The intimate interfacial contact between the IS and CN facilitates the construction of an effective heterojunction, as demonstrated by X-ray photoelectron spectroscopy (XPS) and transmission electron microscopy (TEM). The optimized IS/CN-5 sample exhibits a high CO evolution rate of 483.4 μmol g–¹ h–¹, which is 99 and 6 times as high as that of IS and CN, respectively. The improved charge separation and transfer efficiency, the hollow nanotube structure, and the enhanced CO₂ adsorption ability are the reasons for the excellent photocatalytic activity. Besides, a possible photocatalytic mechanism of CO₂ reduction by the IS/CN heterojunction was proposed on the basis of the band structures. This work provides an effective and facile strategy to construct hollow semiconductor heterojunctions for photocatalytic applications.

Metal-Organic Framework-Derived Tubular In2O3-C/CdIn2S4 Heterojunction for Efficient Solar-Driven CO2 Conversion.

Abstract: Realizing high-efficiency solar-driven CO2 reduction to chemicals and fuels requires high-performance photocatalysts with high utilization efficiency of solar light, efficient charge separation and transfer, and robust adsorption capacity for CO2. In this work, a tubular In2O3-C/CdIn2S4 (IOC/CIS) ternary heterojunction with an intimate interfacial contact was fabricated by pyrolysis of In-MIL-68 and subsequent solvothermal synthesis of CdIn2S4. The construction of a heterojunction promotes the separation and transfer efficiency of photogenerated carriers. The introduction of carbon not only accelerates the interfacial charge migration but also enhances light absorption and CO2 adsorption. The resulting 5IOC/CIS sample presents a remarkably improved photocatalytic CO2 reduction activity with a CO generation rate of 2432 μmol g-1 h-1, much higher than that of the In2O3/CdIn2S4 (IO/CIS) heterojunction (1906 μmol g-1 h-1). Furthermore, the type II charge transfer mechanism of the heterojunction was confirmed by the electron paramagnetic resonance characterization. This work provides new insight into the design and preparation of a highly efficient hollow heterojunction for photocatalytic applications.

Design of melem-based supramolecular assemblies for the synthesis of polymeric carbon nitrides with enhanced photocatalytic activity

Abstract: We design a new supramolecular assembly family as reactants to synthesize highly-photoactive porous polymeric carbon nitride (CN), based on a melem-constructed honeycomb, coupled with the insertion of small triazine analogs. The inclusion of small molecules into the melem-based hexameric rings leads to a highly porous CN with controlled electronic, optical, and catalytic properties, as proven by experimental and theoretical studies. The best-performing photocatalyst demonstrates state-of-the-art activity for hydrogen evolution reaction (HER, H2 generation rate of 8075 μmol h−1 g−1), and CO2 reduction (CO2RR, CO production of 1125 μmol g−1 within 3 h) with high quantum yield efficiencies and excellent stability, owing to the enhanced charge separation and light absorption, appropriate energy bands position, and high specific surface area.

MOF-Derived Hollow Tubular In2O3/MIIIn2S4 (MII: Ca, Mn, and Zn) Heterostructures: Synergetic Charge-Transfer Mechanism and Excellent Photocatalytic Performance to Boost Activation of Small Atmospheric Molecules

Abstract: The rational design of hierarchical In2O3/MIIIn2S4 (MII: Ca, Mn, and Zn) hollow tubular (HT) heterostructures was successfully performed by the preferential growth of ternary metal sulfide (MIIIn2S4) two-dimensional (2D) nanosheets on MIL-68(In) metal–organic framework (MOF) derived hollow tubular In2O3 using a facile low-temperature reflux reaction. The efficiency of HT-In2O3/MIIIn2S4 binary heterojunctions was studied for the photocatalytic activation of small atmospheric molecules. The ultrafast interfacial charge migration, better photoexcited charge separation, and significantly improved photocatalytic H2, NH3, and H2O2 production could be attributed to the narrow band gap energy of the MIIIn2S4 and S-scheme electron migration mechanism between In2O3 and MIIIn2S4 components in the heterostructures. Thanks to its structural and compositional advantages, the optimal HT-In2O3/MIIIn2S4 (1:1) heterostructure photocatalysts exhibited outstanding photocatalytic hydrogen evolution reaction and nitrogen and oxygen reduction reaction activity under visible-light illumination. Among the HT-In2O3/MIIIn2S4 (1:1) hetrostructures, the HT-In2O3/ZnIn2S4 (1:1) photocatalyst displayed the highest H2, NH3, and H2O2 generation (5331, 870, and 5716 μmol g–1 h–1) with conversion efficiency of 34%, 6.5%, and 0.291%, respectively. This study offers a comprehensive analysis on how the coupling of three different d0, d5, and d10 ternary metal chalcogenides MIIIn2S4 with HT-In2O3 affects the photocatalytic H2, NH3, and H2O2 production.