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Polar Aromatic Two-dimensional Dion-Jacobson Halide Perovskites for Efficient Photocatalytic H2 Evolution
Yu Peng1, Yang Zhang1, Xing Wang1
1Key Laboratory for Ultrafine Materials of Ministry of Education, Shanghai Engineering Research Center of Hierarchical Nanomaterials, School of Materials Science and Engineering, East China University of Science and Technology, 130 Meilong Road, Shanghai, 200237, China.
Angewandte Chemie (International Ed. in English)
|February 10, 2024
Summary
Polar materials boost hydrogen production by improving charge separation. New 2D perovskites show enhanced photocatalytic activity, offering a promising route for efficient hydrogen evolution.
Area of Science:
- Materials Science
- Photocatalysis
- Renewable Energy
Background:
- Polar materials with spontaneous polarization (Ps) are promising for photocatalytic H2 evolution due to enhanced carrier separation.
- Traditional inorganic polar materials face limitations like wide band gaps and poor carrier transport, hindering efficiency.
Purpose of the Study:
- To synthesize and investigate novel 2D aromatic Dion-Jacobson (DJ) perovskites for photocatalytic H2 evolution.
- To explore the structure-property relationships of these materials concerning spontaneous polarization and photocatalytic performance.
Main Methods:
- Synthesis of isostructural 2D aromatic DJ perovskites: (2-(2-Aminoethyl)pyridinium)PbI4 (2-APDPI), (3-(2-Aminoethyl)pyridinium)PbI4 (3-APDPI), and (4-(2-Aminoethyl)pyridinium)PbI4 (4-APDPI).
- Characterization of crystal structures, identifying polar space groups for 2-APDPI and 4-APDPI, and a centrosymmetric structure for 3-APDPI.
- Evaluation of photocatalytic H2 evolution efficiency for the synthesized materials.
Main Results:
- Polar 2-APDPI and 4-APDPI exhibit piezoelectric constants (d33) around 40 pm/V.
- Polar 2-APDPI and 4-APDPI showed 3.9- and 2.8-fold increases in H2 evolution, respectively, compared to centrosymmetric 3-APDPI.
- The enhanced performance is attributed to Ps-facilitated separation of photogenerated carriers.
Conclusions:
- Polar 2D DJ perovskites are effective photocatalysts for H2 evolution.
- Spontaneous polarization significantly enhances photocatalytic activity by improving carrier separation.
- This study presents a new strategy for designing efficient polar photocatalysts for sustainable hydrogen production.
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