One-Pot Large-Scale Synthesis of Carbon Quantum Dots: Efficient Cathode Interlayers for Polymer Solar Cells

Abstract

Cathode interlayers (CILs) with low-cost, low-toxicity, and excellent cathode modification ability are necessary for the large-scale industrialization of polymer solar cells (PSCs). In this contribution, we demonstrated one-pot synthesized carbon quantum dots (C-dots) with high production to serve as efficient CIL for inverted PSCs. The C-dots were synthesized by a facile, economical microwave pyrolysis in a household microwave oven within 7 min. Ultraviolet photoelectron spectroscopy (UPS) studies showed that the C-dots possessed the ability to form a dipole at the interface, resulting in the decrease of the work function (WF) of cathode. External quantum efficiency (EQE) measurements and 2D excitation-emission topographical maps revealed that the C-dots down-shifted the high energy near-ultraviolet light to low energy visible light to generate more photocurrent. Remarkably improvement of power conversion efficiency (PCE) was attained by incorporation of C-dots as CIL. The PCE was boosted up from 4.14% to 8.13% with C-dots as CIL, which is one of the best efficiency for i-PSCs used carbon based materials as interlayers. These results demonstrated that C-dots can be a potential candidate for future low cost and large area PSCs producing.

Carbonized Bamboo‐Derived Carbon Nanodots as Efficient Cathode Interfacial Layers in High‐Performance Organic Photovoltaics

“…Chen and co‐workers first demonstrated the use of amino‐based CNDs as efficient zinc oxide (ZnO) or Al‐doped ZnO IFLs for OPVs and observed improvements in PCE of up to 10.24%. [13c] Yang et al used CNDs as a cathode [indium tin oxide (ITO)]‐modifying layer that enhanced the interfacial dipole, thereby decreasing the work function (WF) of the electrode and increasing the performance of derived OPV devices from 4.14% to 8.13% when using a poly[4,8‐bis(5‐(2‐ethylhexyl)thien‐2‐yl)benzo[1,2‐ b :4,5‐ b′ ‐dithiophene‐ co ‐3‐fluorothieno[3,4‐ b ]thiophene‐2‐carboxylate] (PTB7‐Th)/phenyl‐C 71 ‐butyric acid methyl ester (PC 71 BM) blend film as the active layer . These previous studies highlight the potential emerging applications of CNDs as IFLs.…”

Regulated Film Quality with Methylammonium Bromide Addition in a Two‐Step Sequential Deposition to Improve the Performance of Perovskite Solar Cells

“…Several photophysical properties of perovskite materials, such as the tunable band gap, long carrier transport length, and high light absorption efficiency, are mainly responsible for this phenomenon . Importantly, PSCs can be processed by a simple solution route, which is suitable for the large‐scale production of perovskite photovoltaic panels . To date, precursor solution spin‐coating technology, which mainly includes one‐step precursor spin‐coating deposition (OPSD) and two‐step sequential precursor spin‐coating deposition (TSSD), is a cost‐effective technique used widely for the fabrication of perovskite films .…”

“…[11,12] Importantly,P SCs can be processedb yas imple solution route,w hich is suitable for the large-scale production of perovskite photovoltaic panels. [13] To date,precursor solution spin-coating technology, which mainly includes one-step precursors pin-coating deposition (OPSD)a nd two-step sequential precursor spin-coating deposition (TSSD), is ac ost-effective technique used widely for the fabrication of perovskite films. [14,15] Nevertheless,s olution-processed perovskite thin films usually suffer from al ow film qualityw ith ap oorm orphology, many pinholes,a nd low crystallinity,w hich results in al ow devicep erformance.T herefore, it is necessary to regulate the perovskite thin film quality to enhance the performance of PSCs.…”

Synthesis of Novel Fluorescent Carbon Quantum Dots From Rosa roxburghii for Rapid and Highly Selective Detection of o-nitrophenol and Cellular Imaging

“…When the excitation wavelength is in the range of 340–500 nm, the emission band is concentrated at about 400–600 nm depending on the excitation. When excited at 360 nm, the emission wavelength is 450 nm, indicating that the CQDs can convert near UV light to the visible range (Yang et al, 2017 ). The aqueous solution of CQDs ( Figure 4B , left insert) exhibited strong blue PL (right) under UV irradiation (365 nm).…”