Self-Powered Infrared Photodetectors with Ultra-High Speed and Detectivity Based on Amorphous Cu-Based MOF Films

Abstract

Amorphous metal−organic frameworks (aMOFs) start to challenge their crystalline equivalents due to their unique advantages, like lack of grain boundaries, isotropy, flexibility, numerous defects-induced active sites, etc. However, aMOFs are typically synthesized under rigorous conditions, and their properties and applications need to be further explored. In this work, highly transparent p-type amorphous Cu-HHTP films consisting of Cu 2+ and 2,3,6,7,10,11-hexahydroxytriphenylene (HHTP) were synthesized using a simple electrostatic spinning method and identified as p-a-Cu-HHTP. Besides, a p-a-Cu-HHTP/n-Si infrared photodetector (PD) operating on a self-powered basis with ultra-high speed (response time of 40 μs) and detectivity (1.2 × 10 12 Jones) has been developed, with a response time and detectivity that are record values for a MOF-based photodetector. In particular, the p-a-Cu-HHTP/n-Si PD can withstand high temperatures up to 180 °C without property change. Moreover, a flexible metal− semiconductor−metal photodetector based on p-a-Cu-HHTP is constructed, which shows excellent mechanical stability and photoresponse that remain unchanged after bending 120 times, implying its suitability for wearable optoelectronics. The new method to fabricate aMOFs, the unique p-a-Cu-HHTP, and its PDs initiated in this work opens up a new avenue in organic− inorganic hybrid optoelectronics.

Self-assembled metal-oxo clusters for sensitive and low-powered ultraviolet photodetectors

“…6 However, according to our research, only a few studies have reported MOFs as photoabsorption materials in solid-state PDs owing to the difficulty of integrating 3D porous MOFs into 2D optoelectronics. 4,7–11 In most applications for photon energy-to-electrical energy conversion, organic linkers with tunable bandgaps (2.69–3.9 eV) are responsible for generating electron–hole pairs when exposed to the visible-near infrared (Vis-NIR) spectrum, while MOCs with wide bandgaps (≥4 eV) are responsible for generating deep-UV electron–hole pairs. 12 Additionally, MOCs exhibit ultrahigh stability at ambient temperatures (up to 200 °C) and short wavelengths (up to 13.5 nm).…”