Moisture-Light Harvesting Enhanced Hydrovoltaic Electric Generation

Area of Science:

• Materials Science
• Energy Harvesting
• Nanotechnology

Background:

• Moisture-voltaic power generation offers sustainable energy but faces efficiency and adaptability challenges due to environmental complexity.
• Developing flexible, multimodal clean-energy harvesters is essential to overcome limitations of single-mode conversion.

Purpose of the Study:

• To create a flexible, multimodal clean-energy harvester by combining hygroscopic materials with light-responsive components.
• To enhance hydrovoltaic power generation by integrating light harvesting capabilities.

Main Methods:

• A composite material, PSS/AMPS-Na/PVA/BiOBr (PAPBO), was synthesized for the flexible active layer of the moisture-light harvesting electric generator (MLEG).
• The MLEG's performance was evaluated under varying humidity levels and light conditions, measuring open-circuit voltage and short-circuit current.
• The synergistic effect of moisture and light on power output was investigated, focusing on the role of BiOBr in enhancing performance via water oxidation.

Main Results:

• A single MLEG demonstrated a significant open-circuit voltage of 0.77 V and a short-circuit current of 18.73 µA at 75% relative humidity.
• Light harvesting by BiOBr generated long-lived holes, enhancing power output by 60.98% (from 72.75 to 117.11 µW cm⁻²) through water oxidation.
• The device exhibited functionality as a humidity sensor, responding to levels from 10% to 100%.

Conclusions:

• The developed MLEG effectively harvests both moisture and light energy, significantly boosting the hydrovoltaic effect.
• This multimodal energy harvesting approach offers a promising new direction for sustainable power generation and environmental sensing.