Self-powered Photoelectrochemical Research Articles

Shaping the Future of the Neurotransmitter Sensor: Tailored CdS Nanostructures for State-of-the-Art Self-Powered Photoelectrochemical Devices.

Semiconductor-based photoelectrochemical (PEC) test protocols offer a viable solution for developing efficient individual health monitoring by converting light and chemical energy into electrical signals. However, slow reaction kinetics and electron-hole complexation at the interface limit their practical application. Here, we reported a triple-engineered CdS nanohierarchical structures (CdS NHs) modification scheme including morphology, defective states, and heterogeneous structure to achieve precise monitoring of the neurotransmitter dopamine (DA) in plasma and noninvasive body fluids. By precisely manipulating the Cd-S precursor, we achieved precise control over ternary CdS NHs and obtained well-defined layered self-assembled CdS NHs through a surface carbon treatment. The integration of defect states and the thin carbon layer effectively established carrier directional transfer pathways, thereby enhancing interface reaction sites and improving the conversion efficiency. The CdS NHs microelectrode fabricated demonstrated a remarkable negative response toward DA, thereby enabling the development of a miniature self-powered PEC device for precise quantification in human saliva. Additionally, the utilization of density functional theory calculations elucidated the structural characteristics of DA and the defect state of CdS, thus establishing crucial theoretical groundwork for optimizing the polymerization process of DA. The present study offers a potential engineering approach for developing high energy conversion efficiency PEC semiconductors as well as proposing a novel concept for designing sensitive testing strategies.

Self-Powered Immunoassay of Norovirus in Human Stools by π-Electron-Rich Homojunction for Enhanced Charge Transfer.

Norovirus (NoV) stands as a significant causative agent of nonbacterial acute gastroenteritis on a global scale, presenting a substantial threat to public health. Hence, the development of simple and rapid analytical techniques for NoV detection holds great importance in preventing and controlling the outbreak of the epidemic. In this work, a self-powered photoelectrochemical (PEC) immunosensor of NoV capsid protein (VP1) was proposed by the π-electron-rich carbon nitride homojunction (ER-CNH) as the photoanode. C4N2 ring derived from π-rich locust bean gum was introduced into the tri-s-triazine structure, creating a large π-delocalized conjugated carbon nitride homojunction. This strategy enhances the C/N atomic ratio, which widens light utilization, narrows the bandgap, and optimizes the electronic band structure of carbon nitride. By introduction of a π-rich conjugated structure, p-type domains were induced within n-type domains to build the internal electric field at the interface, thus forming a p-n homojunction to boost carrier separation and transfer. The ER-CNH photoanode exhibited excellent photoelectric performance and water oxidation capacity. Since VP1 inhibits the water oxidation of the ER-CNH photoanode, the open-circuit potential of the as-prepared PEC immunosensor system was reduced for detecting NoV VP1. The self-powered PEC immunosensor achieved a remarkably low detection limit (∼5 fg mL-1) and displayed high stability and applicability for actual stool samples. This research serves as a foundation concept for constructing immunosensors to detect other viruses and promotes the application of self-powered systems for life safety.

High-Performance Self-Powered Photoelectrochemical Ultraviolet Photodetectors Based on an In2O3 Nanocube Film.

Ultraviolet photodetectors (UV PDs) have attracted significant attention due to their wide range of applications, such as underwater communication, biological analysis, and early fire warning systems. Indium oxide (In2O3) is a candidate for developing high-performance photoelectrochemical (PEC)-type UV PDs owing to its high UV absorption and good stability. However, the self-powered photoresponse of the previously reported In2O3-based PEC UV PDs is unsatisfactory. In this work, high-performance self-powered PEC UV PDs were constructed by using an In2O3 nanocube film (NCF) as a photoanode. In2O3 NCF photoanodes were synthesized on FTO by using hydrothermal methods with a calcining process. The influence of the electrolyte concentration, bias potential, and irradiation light on the photoresponse properties was systematically studied. In2O3 NCF PEC UV PDs exhibit outstanding self-powered photoresponses to 365 nm UV light with a high responsivity of 44.43 mA/W and fast response speed (20/30 ms) under zero bias potential, these results are superior to those of previously reported In2O3-based PEC UV PDs. The improved self-powered photoresponse is attributed to the higher photogenerated carrier separation efficiency and faster charge transport of the in-situ grown In2O3 NCF. In addition, these PDs exhibit excellent multicycle stability, maintaining the photocurrent at 98.69% of the initial value after 700 optical switching cycles. Therefore, our results prove the great promise of In2O3 in self-powered PEC UV PDs.

Self-powered α-GaOOH nanorod array/FTO photoelectrochemical photodetectors for solar-blind UV photodetection

We have grown α-GaOOH nanorod array/FTO structures with different precursor concentrations by hydrothermal processes without any seed layers. The optical bandgap is ∼5.1 eV, indicating their ability of solar-blind UV photodetection. Photoelectrochemical (PEC) properties of α-GaOOH nanorod array/FTO photodetectors as photoanodes show self-powered solar-blind UV photodetection. Due to the similar width of depletion regions of α-GaOOH nanorod array/FTO PEC photodetectors with changing the precursor concentrations, the peak responsivity is nearly the same. And they also show the similar response time (decay processes) ranging from 0.061s to 0.072s. Compared with the reported bare α-GaOOH nanorod arrays or heterojunctions, the maximum responsivity of 0.29 mA/W at 245 nm is comparable. However, fast collection speed without block of these seed layers between nanorod arrays and FTO results in faster response speed of 0.012 s in this work. Therefore, this article provides basic research in realizing high-performance self-powered α-GaOOH PEC photodetectors without seed layers.

Self-powered photoelectrochemical immunosensing platform for sensitive CEA detection using dual-photoelectrode synergistic signal amplification

Self-powered photoelectrochemical (PEC) sensing, as an emerging sensing mode, can effectively solve the problems such as weak anti-interference ability and poor signal response of individual photoanode or photocathode sensing. In this work, an ITO/Co–CuInS2 photocathode and ITO/WO3@CdS photoanode based self-powered cathodic PEC immunosensor was developed, which integrated dual-photoelectrode to synergistic amplify the signal for highly sensitive and specific detection of carcinoembryonic antigen (CEA). The self-powered PEC sensor could drive electrons transfer through the difference in Fermi levels between the two photoelectrodes without an external bias voltage. The photoanode was introduced to amplify the photoelectric signal, and the photocathode was only designed for the construction of sensing interfaces. The proposed sensor quantitatively determined the target CEA with the detection limit of 0.23 pg/mL and a linear correlation confine of 0.1 pg/mL ∼100 ng/mL. The constructed immunosensing platform exhibited high sensitivity, satisfactory stability and great biological detection selectivity, providing a feasible and effective strategy for the manufacture of new self-powered sensors in high-performance PEC bioanalytical applications.

Recent Trends in Self-Powered Photoelectrochemical Sensors: From the Perspective of Signal Output.

Revolutionary developments in analytical chemistry have led to the rapid development of self-powered photoelectrochemical (PEC) sensors. Different from conventional PEC sensors, self-powered PEC sensors do not require an external power source or complex devices for the sensitive detection of targets. As a result, these sensors have enormous application potential for the development of novel portable sensors. An increasing body of work is making excellent progress toward the implementation of self-powered PEC sensors for detection, but there have been no reviews to date. The present review first introduces the state of the art in the development of self-powered PEC sensors. Then, different types of self-powered PEC sensors are summarized and discussed in detail, including their current, power, and potential. Additionally, single- and dual-photoelectrode systems are classified and systematically compared. Finally, the current developments and major challenges that need to be addressed are also summarized. This review provides valuable insights into the current state of self-powered PEC sensors to promote further progress in this field.

Enhanced performance of self-powered ZnO-based PEC type UV photodetectors by loading GQDs to construct heterojunctions

The construction of semiconductor heterojunctions is an effective approach to enhance the performance of optoelectronic devices. In this study, graphene-quantum-dots (GQDs) were grown on ZnO nanorods arrays in-situ to form intimate heterojunctions. The fabricated photoelectrochemical (PEC) photodetector based on ZnO/GQDs heterojunctions displayed good self-powering characteristics, with an on/off current ratio of approximately 21 at zero bias, which was almost seven-fold higher than that of the bare ZnO device. The responsivity and detectivity of the ZnO/GQDs-based photodetector were also enhanced compared with those of bare ZnO devices. A unique type-II band alignment was established at the ZnO/GQDs heterojunction interface, which facilitated the carrier transfer. Moreover, the ZnO/GQDs heterojunction reduced the passivation of the surface states, resulting in large energy-band bending and an internal electric field at the semiconductor/electrolyte interface, which provided a powerful driving force for the separation and transport of photogenerated carriers. These combined effects enhance the performance of the photodetector, indicating that this approach can be used to fabricate high-performance PEC optoelectronic devices.

Organic semiconductor self-powered photoelectrochemical strategy for L. Monocytogenes detection coupled with target-triggered DNA polymerase activity

The materials involved in studies of self-powered modes are mainly focused on inorganic semiconductor, heterostructure and homojunction. Here, it was found that the self-powered characteristics can be realized based on the photocurrent of polymer organic semiconductor, amino-modified 3,4,9,10-perylenetetracarboxylic dianhydride polymer (PTC-NH2), which being mediated with methylene blue (Mb) and ascorbic acid (AA). A self-powered organic semiconductor photoelectrochemical (PEC) strategy based on co-mediation of Mb and AA was developed for L. monocytogenes detection. This PEC sensing strategy used the target to activate the activity of Taq DNA polymerase. The activated Taq DNA polymerase hydrolysis the DNA which being labeled with Mb. Thereby detaching Mb from magnetic beads (MBs), the strong photocurrent at 0 V with the combined action of AA was produced from PTC-NH2 modified ITO, and realize target detection sensitively. The limit of detection was 85 CFU/mL of L. monocytogenes. This research provides a promising application for the detection of target with the organic semiconductor self-powered PEC sensing strategy. It is anticipated this organic semiconductor self-powered method can give a promising approach for the design and development of low-power-consumption electronics and flexible wearable detection equipment.

Dual-mode self-powered photoelectrochemical and colorimetric determination of procalcitonin accomplished by multienzyme-expressed Ni4Cu2 bimetallic hollow nanospheres and spherical nanoflower-MoS2/Cu2ZnSnS4/Bi2S3

Bacterial infections, viral infections and autoimmune diseases pose a considerable threat to human health. Procalcitonin (PCT) has emerged as a biomarker for the detection of these diseases. To ensure accurate and reliable results, we propose a dual-mode approach that incorporates self-validation and self-correction mechanisms. Herein, we develop a dual-mode self-powered photoelectrochemical (PEC) and colorimetric sensor to determine PCT. The self-powered PEC sensor was constructed with a photoanode of spherical nanoflower-MoS2/Cu2ZnSnS4/Bi2S3 material and a photocathode of CuInS2 material. Ni4Cu2 bimetallic hollow nanospheres (BHNs) possess superoxide dismutase and catalase performance, which facilitate superoxide anion radical (·O2−) and H2O2 circulating generation, promoting the separation of photogenerated electrons and holes to amplify photocurrent signal. Thus Ni4Cu2 BHNs is used as a marker material for PEC sensor. Meanwhile, in colorimetric mode, Ni4Cu2 BHNs converts blue oxTMB to a colourless TMB for colorimetric detection of PCT. Based on this principle, dual-mode determination of PCT with high sensitivity is achieved. The dual-mode method not only demonstrates outstanding properties and practicability, but also presents an effective, highly efficient and reliable method for detecting PCT.

Self-powered photoelectrochemical sensor activated by In2O3/CdTe@ZnS-photoanode coupled with manganese porphyrin-double quenching for methyltransferase detection

A unique self-powered photoelectrochemical (PEC) biosensor is fabricated by integrating CuInS2 nanoflowers (CIS NFs) photocathode and CdTe@ZnS/In2O3 photoanode for sensitive detection of methyltransferase (Dam MTase). CdTe@ZnS quantum dots (QDs)-modified porous In2O3 with excellent photoelectric activity was used as photoanode, and CIS NFs were used as photocathode for biosensing interface. The direct electron transfer and synergistic enhancement of the dual-electrode guarantees sufficient photocurrent driving force for the self-powered PEC system without external power supply. Under the action of Dam MTase and endonuclease Dpn I (Dam-Dpn I), Hp DNA on the electrode was broken down into single-stranded DNA (ssDNA) to immobilize the manganese porphyrin-rich (MnPP) DNA networks. MnPP can not only acted as a burst probe to quench the photocurrent, but also as a mimetic enzyme to catalyze the generation of benzo-4-chloro-hexadienone (4-CD) precipitation in the presence of H2O2, which further reduces the photocurrent, leading to obvious change of PEC signal for Dam MTase detection. The sensor combines excellent photocatalytic performance and anti-interference of self-powered PEC sensor to achieve efficient detection of Dam MTase. The proposed strategy of integrating photocathode and photoanode offers a promising avenue for developing other high-performance PEC sensors for many biologicals.

A self-powered photoelectrochemical aptasensing platform for microcystin-LR cathodic detection via integrating Bi2S3 photoanode and CuInS2 photocathode

Although cathodic photoelectrochemical (PEC) analysis has inherently good anti-interference properties, the relatively insufficient number of holes and rapid recombination rate of carriers result in the relatively low sensitivity of PEC sensors; thus, an additional bias voltage is often required in practical applications. Herein, this study presents a self-powered PEC aptasensing platform to detect microcystin-LR (MC-LR) by integrating an n-type semiconductor Bi2S3 photoanode with a p-type semiconductor CuInS2 photocathode. Based on the difference between the Fermi levels of Bi2S3 and CuInS2, a large number of photogenerated electrons produced by the Bi2S3 photoanode can be supplied to the CuInS2 photocathode along an external circuit, effectively solving the problem of an inconspicuous photocurrent in the cathodic PEC analysis. The constructed sensor can detect MC-LR in the range from 10 fg/mL to 10 ng/mL with a low limit of detection of 9.0 fg/mL (S/N = 3). In addition to its high sensitivity, the aptasensing platform exhibited good anti-interference properties and reproducibility. The constructed self-powered PEC aptasensor can achieve highly efficient MC-LR determination without the addition of any electron donors or acceptors and does not require the application of an additional bias voltage, which uncovers new perspectives for the development of high-performance PEC sensors.

A self-powered photoelectrochemical biosensing platform for H-FABP monitoring mediated by CsPbBr3@COF–V

Advanced bioelectronic detection based on the integration of modern optical electronics and biological systems has a broad prospect. The strategy of cathode signal amplification in self-powered photoelectrochemical (PEC) immunosensors with excellent performance is rarely reported in the field of immune analysis. Herein, the work demonstrates a self-powered PEC biosensor formed with BiOI photocathode and WO3/SnS2/ZnS photoanode, and CsPbBr3@COF–V was used as the photocathode signal quenching source for the quantitative monitoring of heart fatty acid binding protein (H-FABP). The high efficiency and stable self-powered biosensor formed not only provides continuous and powerful photocurrent response for bioanalysis through reasonable stepped band structure, but also effectively eliminates the interference of reducing substances. The quenching source CsPbBr3@COF–V greatly affects the photocurrent response due to steric hindrance, weak conductivity, competition with the substrate for dissolved oxygen and excitation light source. And the intervention of this key factor achieves multiple signal amplification effect and opens up an innovative vision for self-powered PEC immunosensor. Taking H-FABP as a representative analyte, the proposed signal amplification self-powered photoelectrochemical presents a broad linear range from 0.0005 to 150 ng/mL with the detection limit of 0.19 pg/mL.

Self-powered photoelectrochemical immunosensor with triple enhanced photoelectric response for sensitive detection of cTnI

A self-powered photoelectrochemical (PEC) immunosensor triple enhanced photoelectric response was proposed for the sensitive cardiac troponin (cTnI) detection. The self-powered PEC platform was constructed by sulfur indium copper hollow nanocage as a photocathode and hollow nanometer sphere heterojunction (In2S3 @CdIn2S4) as a photoanode, where the coulomb force of distinct photoelectrodes as the driving force effectively improves the photoelectric response without redox-mediator or external potential. In addition, the reverse transfer of photo-generated charge carriers increases the photoelectric response capacity due to the internal electric field effect in type II heterojunction. What is more exciting is that carefully designed hollow materials playing energy conversion function possess compelling properties. Given the advantages of multiple reflection effects in the cavity, thin-shell configuration and large surface, the designed hollow materials possessed a higher photon capture rate, a shorter-range transfer for photon-generated charges, and more active site points for the associated redox reactions, which facilitated the entire photoelectric response process. Based on the above strategies, the proposed PEC immunosensor achieved triple enhanced photoelectric response to present high sensitivity for detecting cTnI. The present study has gone some way to design nanomaterials with superior photoelectric activity, which paves a way for detecting other disease markers in high sensitivity.

Ultrasensitive self-powered photoelectrochemical sensing for enrofloxacin detection by coupling piezoelectric effect with nonmetallic surface plasmon resonance based on ZnO nanorod arrays/WO3-x

Exploring efficient strategy for high-efficiency photoelectric conversion is quite important to design sensitive self-powered photoelectrochemical (PEC) sensing platform. This work designed a high performance self-powered PEC sensing platform by the integration of piezoelectric effect with localized surface plasmon resonance (LSPR) effect based on ZnO-WO3-x heterostructures. Due to the fluid eddy induced piezoelectric effect by magnetic stirring, the piezoelectric semiconductor ZnO nanorod arrays (ZnO NRs) can facilitate the transfer of electrons and holes by generating piezoelectric potentials under external forces, thereby contributing to the performance of self-powered PEC platforms. Such working mechanism of the piezoelectric effect was studied by using the COMSOL software. Moreover, the introduction of defect engineered WO3 (WO3-x) can further broaden the light absorption and promote the charge transfer owing to the nonmetallic surface plasmon resonance effect. Remarkably, due to the synergizing piezoelectric and plasmonic effect, the photocurrent and maximum power output of ZnO-WO3-x heterostructures were enhanced by 3.3-fold and 5.5-fold than that of bare ZnO, respectively. After the immobilization of the enrofloxacin (ENR) aptamer, the self-powered sensor demonstrated an excellent linearity (1 × 10−14 M to 1 × 10−9 M) with a low detection limit of 1.8 × 10−15 M (S/N = 3). This work undoubtedly holds great promise to provide the innovative inspiration for the formation of high-performance self-powered sensing platform, which opens up a new horizon of potential in food safety and environmental monitoring.

High-performance self-powered photoelectrochemical bioassay system with a triphase oxidase enzymatic interface

In the field of biomolecule detection, self-powered photoelectrochemical (PEC) bioassay devices have gained considerable interest with no demand for an external voltage but rather solar energy consumption. In this study, we present a self-powered PEC bioassay system that consists of a nanoporous BiVO4 photoanode coupled to a biophotocathode with a solidliquidair triphase oxidase enzymatic interface. The triphase biophotocathode was assembled by immobilizing oxidase on superhydrophobic Cu2O@TiO2 nanowire arrays. A high and steady interfacial oxygen concentration can be ensured by the triphase biophotocathode with much increased gas mass transport capability, which consequently enhance the kinetics of the oxidase enzymatic reaction as well as the sensing performance of self-powered PEC bioassay system. For the diphase biophotocathode based system, the low solubility and slow diffusion rate of oxygen restrict the kinetics of the oxidase catalytic reaction. As a result, the proposed triphase self-powered PEC bioassay platform exhibits excellent performance with a linear range up to 20 mM for glucose (a model analyst) detection, which is 20 times higher than that of the diphase one. Furthermore, an exceptional anti-interface is obtained by the cathodic bioanalysis approach in the self-powered PEC bioassay system.

Synergistic Signal Amplification-Initiated Innovative Self-Powered Photoelectrochemical Aptasensing: An Ingenious Photocathode Activated by the High-Light-Harvesting Photoanode.

Exploiting ingenious photoelectrodes and innovative signal amplification strategies has the potential to achieve high sensitivity in self-powered cathodic photoelectrochemical (PEC) analysis. In this work, a novel self-powered PEC sensing platform was constructed by integrating a synergistic signal amplification of an ingenious photocathode with a high light-harvesting photoanode. In the dual photoelectrode-based PEC system, the amplified photocurrent signals were induced by a synergistic enhancement: (1) the photocurrent of the BiOBr photocathode was improved by the incorporation of nitrogen-doped graphene; (2) the photocurrent of the self-powered sensor was activated by the high-light-harvesting Bi2S3-C3N4 photoanode. Subsequently, the rational mechanism for synergistic signal amplification was investigated. For the construction of the sensing interface, an aptamer was introduced as the recognition element to specifically capture the streptomycin (STR) target. Under optimal conditions, the constructed self-powered aptasensor has the merits of good linear range (1 × 10-11 to 5 × 10-7 M), acceptable limit of detection (1.18 × 10-12 M), and excellent stability and selectivity for STR detection. Additionally, the proposed self-powered aptasensor showed acceptable accuracy for the detection of STR in water. Hopefully, this might stimulate more interest in designing and constructing novel platforms for exquisite photocathodic monitoring of various contaminants in the environment.

Boosting ultralong chemiluminescence for the self-powered time-resolved immunosensor

The construction of an immunosensor based on ultralong chemiluminescence is challenged due to the shortage of highly efficient initiator for long and stable catalysis. Herein, the heterogeneous Au/Pt@CuO/Cu2O catalyst was used to investigate the structure-activity relationship, while Au/Pt significantly promotes the activity of CuO/Cu2O to catalyze H2O2 and thus produces ·OH and O2•- radicals in highly alkaline solutions, resulting in the strong and long chemiluminescence in the reaction with luminol (10 mL, more than 4 min with 1 μg catalyst). By using the Au/Pt@CuO/Cu2O as the label in the immunoassay, the strong and long chemiluminescence could initiate the photocurrent of the photoelectrochemical (PEC) substrate, and the luminescence time could influence the photocurrent extinction time, thus a self-powered time-resolved PEC immunosensor was developed to detect furosemide, showing a linear relationship between the extinction time and the logarithm of concentrations from 10−3 to 1 μg/L. This work not only experimentally verifies that the Pt–O–Cu bond in heterogeneous catalysts breaks the pH limitation of the Fenton reaction, but also realizes the chemiluminescence for self-powered time-resolved immunosensor, thereby expanding the portable applicability of chemiluminescence in food safety inspection, health monitoring, and biomedical detection without external light source.

A self-powered molecular imprinted photoelectrochemical sensor for streptomycin cathodic detection based on a signal amplification of ZnO/ZnS/Ag2S photoanode

A self-powered molecular imprinted photoelectrochemical (PEC) sensor was first constructed for the sensitive detection of streptomycin (STR) based on ZnO/ZnS/Ag2S photoanode and Fe-doped CuBi2O4 (CBFO) photocathode. A direct electron transfer pathway and enhanced light capture capability was realized by elaborate design of ZnO/ZnS/Ag2S core/shell/shell (CSS) structure. Meanwhile, a well-matched band-edge energy level between ZnO, ZnS and Ag2S not only accelerated the separation of photogenerated carriers, but also amplified photoelectric signal. Molecularly imprinted polymers (MIPs) were prepared at the CBFO photocathode, which could recognize and bind target molecules with selectivity. The inherent deviation between the Fermi level of the photoanode and the photocathode without an external power supply guarantees sufficient photocurrent driving force for the self-powered system. The proposed self-powered PEC sensor improved anti-interference ability and sensitivity, which completed rapid detection for STR, displayed a wider detection range (0.01 nM-10 mM) and lower detection limit (0.0053 nM, S/N = 3), also exhibited good stability and outstanding reliability. This study demonstrates that a rapid, miniaturized self-powered sensing platform has great practical potential for monitoring food safety.

A self-powered photoelectrochemical molecular imprinted sensor for chloroquine phosphate with enhanced cathodic photocurrent via stepped energy band alignment engineering

Fabricating a self-powered photoelectrochemical (PEC) sensor with superior performances and cost-effective design is highly desirable but still remains challenges. Herein, we develop a self-powered PEC molecular imprinted (MIP) sensor integrating WO3/TiO2 photoanode and gold nanoparticles modified carbon intercalated MoS2 photocathode for highly sensitive and specific detection of chloroquine phosphate (CQP). By constructing a reasonable stepped energy band structure, the electrons are efficiently transferred driven by the Fermi energy level gap between photoanode and photocathode, which amplifies the cathodic photocurrent. Furthermore, the mechanism of electron transfer driven by the Fermi energy level gap in the self-powered sensor was demonstrated for the first time by density functional theory (DFT). The Molecular imprinted polymer was modified on the photocathode as recognition element, which avoids the interference of reducing substances in the samples and complex biometric reactions. Under optimal conditions, the proposed MIP sensor for CQP presents the detection limit of 0.11 μM with a broad linear range from 10−6 M to 10−3 M. This work presented an innovative design strategy for constructing self-powered sensor.

Self-powered photoelectrochemical aptasensor based on AgInS2@Co/Ni-UiO-66@CDs photoelectrode for estradiosl detection.

A self-powered photoelectrochemical (PEC) aptasensor was constructed to sensitively detect 17β-estradiol (E2). Firstly, a reasonable AgInS2@Co/Ni-UiO-66@Carbon Nanodots (CDs) photoelectrode with excellent photoelectrochemical performance was built by a simple two-step preparation method. The Co and Ni doping markedly improved the activity of UiO-66;the matched energy level of AgInS2 and Co/Ni-UiO-66 promoted the separation of electron-hole pairs, and the coupling of CDs further enhanced the conductivity and light utilization. Therefore, a steady anode-photocurrent signal output was obtained in 0.0V bias voltage, providing a reliable photoelectric translating platform for assembling a self-powered PEC aptasensor. The E2-aptamer was adopted as a recognition unit to enhance the selectivity and sensitivity of the proposed aptasensor. The specific recognition reaction between E2 and aptamer administering to a raised photocurrent signal and the concentration of E2 was quantified by counting the fluctuation of the anode-photocurrent signal. The linear response range of the PEC aptasensor was 1.0 × 10-5-10nmol/L, and the detection limit (S/N = 3) was lower than 3.0 fmol/L under optimal conditions. The fabricated aptasensor exhibited admirable selectivity, high sensitivity, rapid response, and wide linear range, demonstrating an extensive application prospect for environmental endocrine disruptor detection.