New Insights toward Efficient Charge-Separation Mechanism for High-Performance Photoelectrochemical Aptasensing: Enhanced Charge-Carrier Lifetime via Coupling Ultrathin MoS₂ Nanoplates with Nitrogen-Doped Graphene Quantum Dots

Abstract

Deeply understanding the internal mechanism of the photoelectrohemical (PEC) process is conducive to fabricate high-performance PEC biosensors. In this work, we proposed a new insight toward an efficient charge-separation mechanism in high-performance PEC biosensors. Specifically, we disclosed that the lifetimes of photogenerated charge carriers of ultrathin MoS nanosheets could be prolonged by approximately millisecond time scales after a proper mole ratio of NGQDs were coupled, leading to the promoted charge separation and a giant photocurrent signal magnification. Benefiting from the dramatic signal amplification and the introduction of acetamiprid aptamer, subfemtomolar level detection of acetamiprid is achieved, which makes our strategy among the most sensitive electronic approaches for PEC-based monitoring of targets. This study was beneficial to further understand the charge-separation mechanism in PEC biosensing, which paved the way for the development of more efficient PEC biosensors.

“On–Off–On” Photoelectrochemical/Visual Lab-on-Paper Sensing via Signal Amplification of CdS Quantum Dots@Leaf-Shape ZnO and Quenching of Au-Modified Prism-Anchored Octahedral CeO2 Nanoparticles

“…The photoluminescence (PL) technique was exploited to verify the separation efficiency of the photoinduced electrons and holes. It was well-known that the PL intensity with higher value signified higher recombination possibility of electron–hole pairs, whereas weaker intensity indicated lower recombination probability of photoexcited charge carriers . Obviously, PO-CeO 2 NPs displayed much lower PL intensity compared with O-CeO 2 NPs in Figure S10B, which indicated that PO-CeO 2 NPs could exhibit more effective separation of photogenerated charge carriers.…”

Modulating Charge Carrier Efficient Separation Enabled by Lewis Base Modification in Paper‐based Photoelectrochemical Sensor

“…To reveal the efficiency separation of photo-induced charge carries, the steady-state photoluminescence (PL) measurements were employed. As we all know, the higher value of PL intensity represents the higher recombination of photo-induced charge carriers, while weaker one means lower recombination probability [26,27]. Figure 3a illustrated the PL emission of PHT arrays (black curve) and PHT/WO 4 samples (red curve).…”

Fluorometric Aptasensor for Determination of Escherichia coli OI57:H7 by FRET Effect between Aminated Carbon Quantum Dots and Graphene Oxide

“…2B, the lattice spacing of 0.3 nm was observed, indicating the present of NH2-CQDs-aptamer, which further confirmed that NH2-CQDs-aptamer was successfully loaded on GO. 31…”