Scalable Atomically Interfaced Heterostructure Photoelectrodes for Broadband Solar Energy Harvesting and Stable...

Area of Science:

• Materials Science
• Electrochemistry
• Nanotechnology

Background:

• Photoactive batteries (PBs) integrate photoactive materials into battery architectures to enhance performance using photogenerated charge carriers.
• Developing efficient photoelectrode materials is crucial for advancing PB technology.

Purpose of the Study:

• To report the scalable synthesis of WO_3-x-WS₂ nanosheet (NS)-based heterostructures for photoelectrodes in lithium-ion PBs.
• To investigate the light harvesting, charge separation, and electrochemical performance of these novel heterostructures.
• To demonstrate a design framework for optimizing charge-carrier dynamics in PBs.

Main Methods:

• Scalable synthesis of WO_3-x-WS₂ NS-based heterostructures.
• Fabrication of photoelectrodes for Li-ion PBs.
• Electrochemical performance testing under dark and illuminated conditions.
• Characterization of light harvesting and charge carrier dynamics.
• Implementation of a dual-mesh current collector.

Main Results:

• WO_3-x-WS₂ NS heterostructures exhibit broadband light harvesting (300-800 nm) and efficient photocharge carrier separation.
• Stable electrochemical performance with 80% capacity retention after 300 cycles and a specific capacity of 515.94 mAh g^-1 (100-1000 mA g^-1).
• Illumination (∼12 mW cm^-2) enhanced PB kinetics, increasing specific capacity by 35-59%.
• Dual-mesh current collector improved active mass loading and light-matter interaction, further boosting specific capacity.

Conclusions:

• Atomically interfaced WO_3-x-WS₂ NS heterostructures are promising photoelectrode materials for high-performance Li-ion PBs.
• The developed design framework effectively optimizes charge-carrier dynamics for enhanced PB performance.
• This work establishes a viable pathway toward practical, high-performance PBs for Internet of Things (IoT) applications.