Perovskite CsCuCl_xBr_3-x Microcrystals: Band Structure, Photochemical Stability, and Photocatalytic Properties

Area of Science:

• Materials Science
• Photocatalysis
• Renewable Energy

Background:

• Lead-based metal halide perovskites (MHPs) offer excellent photoelectric properties but face toxicity concerns hindering their application.
• Developing non-toxic alternatives is crucial for advancing solar fuel generation technologies.

Purpose of the Study:

• To synthesize and evaluate non-toxic CsCuClxBr3-x (x=1, 2, 3) microcrystals for photocatalytic hydrogen evolution.
• To investigate the influence of sacrificial agents and solution chemistry on the performance and stability of these perovskites.

Main Methods:

• Synthesis of CsCuClxBr3-x microcrystals.
• Photocatalytic hydrogen evolution experiments using ethanol and HX (X=Cl, Br) as sacrificial agents.
• X-ray diffraction (XRD) for phase transition monitoring.
• Analysis of photogenerated charge carrier dynamics.

Main Results:

• CsCuCl3 microcrystals exhibited superior hydrogen evolution performance in both HX and ethanol.
• The photogenerated hole (h+) was identified as critical for photocatalytic hydrogen production.
• CsCuCl3 demonstrated remarkable stability in saturated HCl aqueous solutions, maintaining a dynamic dissolution-precipitation equilibrium.
• A hydrogen production rate of 103.98 μmol g-1 at 210 min was achieved for CsCuCl3.

Conclusions:

• CsCuCl3 microcrystals are a promising non-toxic material for efficient and stable photocatalytic solar fuel generation.
• The study highlights the potential of halide perovskites in overcoming stability issues through controlled dissolution-precipitation.
• These findings expand the application prospects of CsCuCl3 in sustainable energy technologies.