Ultrabroadband photodetection based on graphene ink

Area of Science:

• Materials Science
• Nanotechnology
• Optoelectronics

Background:

• Graphene's unique electronic properties make it a promising material for optoelectronic devices.
• Developing broadband photodetectors is crucial for various applications, including imaging and sensing.
• Nanoparticle functionalization can enhance the performance of graphene-based devices.

Purpose of the Study:

• To investigate the photodetection capabilities of graphene inks functionalized with noble metal nanoparticles.
• To achieve broadband photodetection across ultraviolet, visible, and near-infrared regions.
• To compare the performance of gold and silver nanoparticle-functionalized graphene inks.

Main Methods:

• Fabrication of interdigitated electrodes on a silicon dioxide/silicon substrate.
• Preparation of graphene inks functionalized with gold nanoparticles, silver nanoparticles, or gold nanoparticles encapsulated with bovine serum albumin.
• Deposition of functionalized graphene inks onto the electrodes.
• Characterization of photodetection performance across a wide spectral bandwidth (215-2500 nm) at a 0.1 V bias.

Main Results:

• Photodetection was achieved across a broad spectral range (ultraviolet, visible, near-infrared) using functionalized graphene inks.
• Gold-functionalized graphene inks exhibited responsivities greater than 1 mA W⁻¹.
• Silver-functionalized graphene inks demonstrated a four-fold increase in responsivity, reaching a record value of 13.7 mA W⁻¹ in the near-infrared region.

Conclusions:

• Graphene inks functionalized with silver nanoparticles offer superior responsivity for broadband photodetection.
• These materials show significant potential for developing high-performance photodetectors across a wide spectral range.
• The study highlights the effectiveness of nanoparticle engineering in enhancing graphene-based optoelectronic devices.