Bright short-wavelength infrared organic light-emitting devices

Abstract

Organic light-emitting devices (OLEDs) emissive in short-wavelength infrared (SWIR) region are attractive for ground-breaking applications in biosensors, biomedical imaging and next-generation optoelectronic devices. However, fabrication of such devices with high radiance has not yet been achieved, owing to an intrinsic limitation imposed by the energy-gap law, which leads to extremely low emission efficiency. Here we report that acceptor-donor-acceptor (A-D-A) type molecules with high co-planarity, rigidity of π-conjugated backbones, extremely small reorganization energy and electron-phonon coupling factor are capable of simultaneously providing strongly suppressed non-radiative recombination rate, and high operation stability at high current density. We achieve electrically driven SWIR with irradiance of 3.9 mW cm -2 (corresponding to 7% of direct sunlight infrared irradiance), which is the brightest emission to date and surpasses that of any previously reported SWIR OLEDs sixty-fold. These findings should open a wide avenue to a new class of organic SWIR light sources for broad applications.

Room-Temperature, Multigram-Scale Synthesis and Conversion Mechanism of Highly Luminescent Lead Sulfide Quantum Dots

“…The optical powers of the NIR light increase with increasing current and approach the maxima of 7.9 mW at 160 mA. If the 13.8% unmeasured part (λ = 1,050–1,150 nm) is calculated, the actual NIR optical power could reach 9.2 mW, which is comparable to 10 mW as seen for InGaAs-based LEDs …”

Ultrafast energy transfer from polymer donors facilitating spectral uniform photocurrent generation and low energy loss in high-efficiency nonfullerene organic solar cells

“…S2c, ESI † for the Y6 crystal structure), which is beneficial for charge separation. [48][49][50] In addition, thanks to the characteristic wavefunction delocalization, 16,51 low reorganization energy 52 and orbital hybridization 46,53 of NFA molecules, new photocarrier generation channels (e.g. self-stimulated dissociation, 54 i-EX, 28 CTX 27 ) have also been revealed in NFA systems, enabling efficient hole transfer with near zero donor-NFA HOMO offsets.…”

Blue-light-excitable pure and efficient short-wave infrared luminescenceviaCr3+→ Yb3+energy transfer in a KYbP2O7:Cr3+phosphor

“…Short-wave infrared (SWIR, 900-1700 nm) light sources have attracted a great deal of interest for their promising advanced applications in non-destructive identification, night vision, biomedical imaging and optical communication. [1][2][3][4][5] Recently, the urgent requirement to couple SWIR emitters with portable electronic devices for multifunctional applications necessitated the development of light sources with compact size, long lifetime, high conversion efficiency, and low product price. [6][7][8][9] Conventional light sources such as halogen-tungsten lamps have already been commercialized and widely used because of their super-broadband emission ranging from near-UV to middle-IR, but they are restricted by large body size, high power consumption, short lifetime, and high working temperature.…”