Enhanced Photothermal Conversion through 2D/0D Nano-Heterojunction Engineering for Highly Efficient Solar...

Area of Science:

• Materials Science
• Nanotechnology
• Renewable Energy

Background:

• Two-dimensional (2D) materials are explored for solar desalination, but conventional options like MXenes and TMDs have limitations.
• Metal phosphorus trichalcogenides (MPCh3) present tunable bandgaps (1.2-3.5 eV) and superior photothermal properties, ideal for solar applications.
• Hybrid van der Waals heterostructures enhance light-matter interactions in 2D materials.

Purpose of the Study:

• To synthesize and characterize FePS3 nanosheets/carbon nanodots (CNDs) 2D/0D nanoheterojunctions.
• To evaluate the photothermal performance and solar desalination efficiency of these novel nanoheterojunctions.
• To elucidate the synergistic mechanisms behind enhanced photothermal conversion and water evaporation.

Main Methods:

• Synthesis of FePS3 nanosheets/CNDs 2D/0D nanoheterojunctions.
• Integration into a 3D photothermal evaporator for performance testing.
• Characterization using UV-Vis-NIR absorbance, temperature measurements, water evaporation rate determination, fs-TAS, PL analysis, and FDTD simulations.

Main Results:

• The FePS3/CNDs nanoheterojunctions achieved 90.6% average absorbance (UV-NIR) and a 42 °C temperature increase under 1 sun illumination.
• A high water evaporation rate of 1.68 kg m-2 h-1 was recorded under identical conditions.
• Synergistic effects from CNDs and nanoheterojunction formation enhanced localized heating, light absorption, and nonradiative transitions.

Conclusions:

• Rational design of MPCh3-based nanoheterojunctions significantly boosts photothermal conversion efficiency.
• These engineered materials show transformative potential for solar desalination and other photothermal technologies.
• The FePS3/CNDs hybrid system offers a high-performance solution for efficient solar energy utilization.