Recent Advances in Solution‐Processable Organic Photodetectors and Applications in Flexible Electronics

Abstract

Organic photodetectors (OPDs) are promising for applications in flexible electronics due to their advantages of excellent photodetection performance, cost-effective solution-fabrication capability, flexible device design, and adaptivity to manufacturability. This review outlines the recent advances in the development of high-performance OPDs and their applications in flexible electronics. The approaches to developing different noise reduction methods, filter-free spectral selective detection, flexible OPDs, and scale-up production of flexible OPDs through solution-fabrication processes are discussed. Applications of the OPD technology ultimately result in the materialization of wearable units, flexible and compact information sensors at commercially viable costs, including wearable health self-monitoring devices, flexible optical communication systems, and flexible large-area image sensors.

In Situ Observation of Morphological and Oxidation Level Degradation Processes within Ionic Liquid Post-treated PEDOT:PSS Thin Films upon Operation at High Temperatures

“…The reason for this lies in the advantageous properties of organic semiconductors, like their easy and low-temperature processability from solution, facilitating a low-cost and energyefficient fabrication with large-scale deposition techniques like printing, spray, or dip coating. 21,22 Furthermore, the raw materials are usually abundantly available and enable low or nontoxic, lightweight, and mechanical flexible devices. Besides organic small molecules, like oligothiophene, fullerene, perylene, or anthracene derivatives, an intense research interest lies in polymer-based organic semiconductors, usually based on polyacetylene, polypyrrole, polyphenylene vinylene, or polythiophene backbones.…”

“…Whether in lightweight organic photovoltaics, − flexible organic light-emitting diodes, − organic sensors, − organic field-effect transistors, − transparent organic electrodes, − or organic thin-film thermoelectrics, − nowadays, organic semiconductors play a fundamental part in the development of new trendsetting devices and applications. The reason for this lies in the advantageous properties of organic semiconductors, like their easy and low-temperature processability from solution, facilitating a low-cost and energy-efficient fabrication with large-scale deposition techniques like printing, spray, or dip coating. , Furthermore, the raw materials are usually abundantly available and enable low or nontoxic, lightweight, and mechanical flexible devices. Besides organic small molecules, like oligothiophene, fullerene, perylene, or anthracene derivatives, an intense research interest lies in polymer-based organic semiconductors, usually based on polyacetylene, polypyrrole, polyphenylene vinylene, or polythiophene backbones. − In particular, great attention is paid to the blend poly­(3,4-ethylene dioxythiophene):polystyrene sulfonate (PEDOT:PSS), which comprises the insoluble, however, excellent p-type semiconductor PEDOT and PSS, a water-soluble partly negatively charged polyanion. , Besides the before mentioned advantages of organic semiconductors, PEDOT:PSS also exhibits a tunable and potentially high hole conductivity of up to 10 3 S cm –1 , which even competes with commonly used transparent electrode materials like indium tin oxide (ITO). − The key to the easy tunability of optoelectronic properties lies in the particular polymer blend morphology of PEDOT:PSS. ,, In an aqueous solution, the insoluble π-conjugated PEDOT chains agglomerate, forming a PEDOT enriched core, which is surrounded and stabilized by a shell of water-soluble PSS.…”

Advances in Flexible Organic Photodetectors: Materials and Applications

“…The use of the HTL and ETL in an OPD facilitates charge extraction at the BHJ/electrode interfaces, resulting in photocurrent generation. A photodiode’s photoresponse is based on collecting photogenerated charge carriers, allowing it to operate either self-powered or with a reverse bias [ 20 ].…”

“…There has been a great deal of progress reported with solution-processed PDs based on QDs and perovskites. However, toxic materials are used in these PDs for wearable electronics, which remain a cause for concern [ 20 ]. Additionally, PDs based on two-dimensional materials are limited in spectral response, response time, air stability, and fabrication for large areas [ 21 ].…”

Modification of Electrode Interface with Fullerene-Based Self-Assembled Monolayer for High-Performance Organic Optoelectronic Devices

“…Organic electronic devices, in which organic semiconductor materials are the active materials, are among the most promising devices for the realization of future wearable electronics because of the inherent high mechanical flexibility and easy processability of organic materials [ 1 , 2 , 3 , 4 , 5 , 6 , 7 ]. To achieve high-performance organic electronic devices, it is essential to achieve proper electrical contact between the organic semiconductor and electrode materials [ 8 , 9 , 10 , 11 , 12 , 13 ].…”