ZnO-Heterostructures-Based Label-Free, Visible-Light-Excited

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MoS2/ZnO-Heterostructures-Based Label-Free, Visible-Light-Excited Photoelectrochemical Sensor for Sensitive and Selective Determination of Synthetic Antioxidant Propyl Gallate Fangjie Han,†,‡ Zhongqian Song,† Mian Hasnain Nawaz,†,∥ Mengjiao Dai,†,‡ Dongfang Han,§ Lipeng Han,*,§ Yingying Fan,§ Jianan Xu,† Dongxue Han,*,†,‡,§ and Li Niu†,§

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State Key Laboratory of Electroanalytical Chemistry, c/o Engineering Laboratory for Modern Analytical Techniques, Changchun Institute of Applied Chemistry, Chinese Academy of Sciences, Changchun 130022, China ‡ University of Science and Technology of China, Hefei 230026, China § Center for Advanced Analytical Science, c/o School of Chemistry and Chemical Engineering, Guangzhou University, Guangzhou 510006, China ∥ Interdisciplinary Research Centre in Biomedical Materials (IRCBM), COMSATS University Islamabad, Lahore Campus, Islamabad 45550, Pakistan S Supporting Information *

ABSTRACT: Propyl gallate (PG) as one of the important synthetic antioxidants is widely used in the prevention of oxidative deterioration of oils during processing and storage. Determination of PG has received extensive concern because of its possible toxic effects on human health. Herein, we report a photoelectrochemical (PEC) sensor based on ZnO nanorods and MoS2 flakes with a vertically constructed p−n heterojunction. In this system, the n-type ZnO and p-type MoS2 heterostructures exhibited much better optoelectronic behaviors than their individual materials. Under an open circuit potential (zero potential) and visible light excitation (470 nm), the PEC sensor exhibited extraordinary response for PG determination, as well as excellent anti-inference properties and good reproducibility. The PEC sensor showed a wide linear range from 1.25 × 10−7 to 1.47 × 10−3 mol L−1 with a detection limit as low as 1.2 × 10−8 mol L−1. MoS2/ZnO heterostructure with proper band level between MoS2 and ZnO could make the photogenerated electrons and holes separated more easily, which eventually results in great improvement of sensitivity. On the other hand, formation of a five membered chelating ring structure of Zn(II) with adjacent oxygen atoms of PG played significant roles for selective detection of PG. Moreover, the PEC sensor was successfully used for PG analysis in different samples of edible oils. It demonstrated the ability and reliability of the MoS2/ZnO-based PEC sensor for PG detection in real samples, which is beneficial for food quality monitoring and reducing the risk of overuse of PG in foods.

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In past decades, various strategies and techniques have been reported for the detection of PG including high-performance liquid chromatography,4 gas chromatography−mass spectrometry,5 electrochemical method,6 and so on. Unfortunately, most of the established protocols involve ineluctable disadvantages. More specifically, chromatographic technique requires complex and high-cost instrumentation and timeconsuming operation. With respect to electrochemical analysis, the electrodes are prone to fouling in the reaction process, resulting in poor stability and reproducibility. Recently, as a burgeoning technology, photoelectrochemical (PEC) methodology has been developed and attracted great attention due to

ynthetic antioxidants are widely used as additives to retard oxidation reactions in foodstuffs.1,2 For example, in order to prevent rancidity and aftertaste caused by automatic oxidation of oils or oil-based foods in the air, besides oxygen removal storage strategy, propyl gallate (PG) is commonly used as an oil-soluble additive in these foodstuffs, which not only can prevent rancidification of edible oils but also can have advantages of high thermal stability and antilipid peroxidation activity.1 However, some studies indicated that excess use of these synthetic antioxidants may cause negative health effects due to its toxicity to hepatocytes.2,3 Therefore, its usage in food products is regulated strictly by law in many countries with the permitted maximum limitation of 0.1 g/kg.2 On the basis of this, it is of great importance to develop effective analytical methods for quantitative detection of PG with high sensitivity and selectivity, which is beneficial for food quality monitoring and reducing the risk of overuse of PG in foods. © XXXX American Chemical Society

Received: April 18, 2019 Accepted: June 17, 2019 Published: June 17, 2019 A

DOI: 10.1021/acs.analchem.9b01889 Anal. Chem. XXXX, XXX, XXX−XXX

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(PBS buffer) was made from sodium phosphate (NaH2PO4/ Na2HPO4, 81:19 (molar ratio)) and sodium chloride, which were dissolved in deionized water at final concentrations of 10 mmol L−1 (pH = 7.4). ITO electrodes were cleaned with NaOH (1 mol L−1) and H2O2 (30%), sonicated in acetone and water, and dried under ambient conditions. Edible oils (peanut oil and corn oil) were bought from a supermarket. Apparatus. Transmission electron microscopic (TEM) and high-resolution transmission electron microscopic (HRTEM) images were obtained by a TECNAI G2 high-resolution transmission electron microscope operating at 200 kV. Scanning electron microscopy (SEM) assisted surface analysis and energy dispersive X-ray spectroscopy (EDX) were performed by field emission scanning electron microscopy (FE-SEM; XL30ESEM-FEG). X-ray photoelectron spectroscopy (XPS) was measured on an ESCALAB-MKII250 photoelectron spectrometer with Al Kα X-ray radiation as the X-ray source for excitation. The UV−vis diffuse reflectance spectra (DRS) were recorded from a Hitachi U-3900 spectrometer equipped with an integrating sphere assembly, where BaSO4 was employed as the reference sample. Electrochemical impedance spectroscopy (EIS) measurements were recorded on a Solartron 1255 B frequency response analyzer (Solartron Inc., U.K.) in a mixed solution of 1 mmol L−1 [Fe(CN)6 ]3‑/4‑ and 0.1 mol L−1 KCl aqueous solution (amplitude, 5 mV; 10−1 to 105 Hz). All of the other electrochemical measurments were performed on a CHI920C electrochemical workstation at room temperature, using a conventional three-electrode system, comprising modified ITO glass as the working electrode, a platinum wire as the auxiliary electrode, and a Ag/AgCl (3 mol L−1 KCl) as the reference electrode. The PBS solution as supporting electrolyte was bubbled with N2 for 15 min before each experiment to remove oxygen. A light-emitting diode (LED) light (3 W, 470 nm) was used as the excitation source of the PEC sensor. Preparation of MoS2/ZnO Heterostructures. The decoration of ZnO nanorods on ITO glass substrate was performed via aqueous ammonia-mediated hydrothermal process.34 Briefly, 1.19 g of Zn(NO3)2·6H2O was added to 20 mL of deionized water to obtain a transparent solution. Under modest stirring, aqueous ammonia was drop by drop injected into the above-mentioned solution with the gradual appearance changing from turbid to clear; the solution was controlled to pH 11. Afterward, the mixture was transferred to a Teflon-lined stainless-steel autoclave, where ITO glass pieces of desired dimensions were placed, and heated at 90 °C for 2 h. The obtained precipitates were then intensively washed with deionized water before drying at 50 °C for 5 h. Afterward, in a typical procedure, 29.36 mg of (NH4)2MoS4 was dispersed in 30 mL of DMF solution and stirred for 30 min. The solution was again transferred into a 50 mL Teflon-lined stainless autoclave with ZnO-modified ITO and kept at 200 °C for 15 h.35 After natural cooling to room temperature, the MoS2/ZnO heterostructures decorated ITO were washed with distilled water several times and dried at 80 °C in an oven for 12 h to improve the adhesion. Preparation of PEC Sensor. The modified ITO electrode was fastened on the PEC cell first, and then 4 mL of PBS solution was introduced to the photoelectrochemical cell according to our previous report.14,15 The light source was then turned “ON”, and the blank data were collected, which was followed by detection experiments of samples of different

its melded advantages of both optical and electrochemical strategies such as easy operation, rapid response, and low cost.7−13 Ma et al. presented a PEC method using utg-C3N4/ TiO2 as a photovoltaic material that was successfully used in the flow measurement of the antioxidant capacity of total antioxidants including gallic acid, caffeic acid, and catechin.14 Wang et al. reported a PEC device based on Mo-doped BiVO4 for analyzing the antioxidant capacity in fruits.15 However, this research focused on the determination of global antioxidant capacity in food.14,15 The detection of the individual antioxidant content should not be overlooked, because it is the basis of food health and safety. Since the optoelectronic material is considered the key element in the PEC platform which plays an essential role to the performance of PEC sensing,16−18 seeking a preferable candidate for futher precision antioxidant assay is greatly encouraged. Generally, the ideal photoactive materials exhibit high visible-lightharvesting capability to enhance the light absorption and possess fast charge transport in order to separate the electron/ hole (e−/h+) pairs and suppress charge recombination.18,19 As a kind of metal oxide semiconductor, zinc oxide (ZnO) owns the gift of high electrons mobility, high melting point, and good chemical stability, which has been widely studied in many applications, such as sensors, photocatalysts, and photovoltaics.20−24 However, the wide bandgap (3.37 eV) of ZnO restricts its light absorption within the ultraviolet range, which accounts for only a small portion of sunlight.23,24 In addition, as a member of transition-metal dichalcogenide, molybdenum disulfide (MoS2) exhibits excellent electronic and optical prosperities (narrow bandgap, 1.85 eV),19,25−27 which is widely used in hydrogen evolution, solar cells, photodetectors, and biosensors.28−33 It is reasonable to assume that the heterostructure between MoS2 and ZnO should endow favorable energy band alignment and is beneficial for charge separation.33 Herein, ZnO nanorods and MoS2 flakes with a vertically constructed p−n heterojunction was synthesized on indium tin oxide (ITO) glass substrate via two-step solvothermal reactions. Such a novel heterostructure was then successfully employed as optoelectronic materials in a PEC platform for antioxidant analytical determination in food, laying a foundation for label-free PEC determination of antioxidant in food. The resulting biomolecule-free PEC sensor possessed a series of merits, such as rapid response, surface antifouling, and high sensitivity in determination of PG. In addition, the ITO electrode modified with MoS2/ZnO heterostructures can be reused for several times with good stability and reproducibility. Furthermore, the possible mechanism based on excellent selectivity and sensitivity of this PEC sensor was also proposed in depth, which provided a new method for design of photocatalyst with consideration of the composition and interaction with the detection molecule.

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EXPERIMENTAL SECTION Materials and Reagents. Zinc nitrate hexahydrate (Zn(NO 3 ) 2 ·6H 2 O), ammonium tetrathiomolybdate ((NH4)2MoS4), propyl gallate (PG), tertiary butylhydroquinone (TBHQ), butylhydroxyanisole (BHA), butylated hydroxytoluene (BHT), and DL-α-tocopherol (VE) were bought from Sigma-Aldrich, China. N,N-Dimethylformamide (DMF) and ethanol were obtained from Beijing Chemicals Corp., China. Unless otherwise stated, reagents were used as received without further purification. The phosphate buffered saline B

DOI: 10.1021/acs.analchem.9b01889 Anal. Chem. XXXX, XXX, XXX−XXX

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Figure 1. (a) Schematic illustration for preparation of MoS2/ZnO heterostructures on ITO. (b) Top-view SEM image of the MoS2/ZnO heterostructures on ITO. (d−g) Zn, O, Mo, and S elemental EDX mappings of the MoS2/ZnO heterostructures as shown in panel c. TEM images (h−j) and (k) HRTEM image of the as-prepared MoS2/ZnO heterostructures (scale bars: h, 0.5 μm; i and j, 50 nm; k, 5 nm).

concentrations. During the sample analysis, the photocurrent was obtained following this rule: I = Isample − Iblank (Isample is the photocurrent produced by sample; Iblank is the photocurrent without sample). The photocurrent measurements were performed in triplet to obtain the average values.

Insights into the chemical states and phase information on the MoS2/ZnO heterostructures were investigated by XPS analysis as shown in Figure 2a. The wide-scan XPS spectrum demonstrates merely uniform Zn, O, Mo, and S element distribution consistent with the results of EDX. Figure 2b shows the XRD patterns of ZnO, MoS2, and MoS2/ZnO heterostructures. It can also be seen in Figure 2b that the main four peaks appearing at 2θ values of 32.2, 36.2, 47.1, and 56.4 correspond to the crystal planes (100), (101), (102), and (103) of ZnO, respectively.39 All of the peaks were consistent with the wurtzite structured ZnO. Moreover, a reflection peak centered at 14.08° indicates the existence of MoS2 in the heterostructures.35 The DRS results of ZnO and MoS2/ZnO are shown in Figure 2c. Compared to the pristine ZnO, the introduction of MoS2 induced increased light absorption intensity to a larger extent in visible light regions. In addition, the charge carrier migration within the heterostructure was characterized by EIS plot (shown in Figure 2d). MoS2/ZnO heterostructures showed smaller Nyquist semicircle radii than ZnO, indicating less electron transfer resistivity and hence their better conductivity. Optimization of Experimental Conditions. Generally, the working potential has a great effect on current intensity and charge measurement.39 In addition, the wavelength of irradiation is another key factor for the photoelectrochemical

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RESULTS AND DISCUSSION Characterization of MoS2/ZnO Heterostructures. The preparation of MoS2/ZnO heterostructures is illustrated in Figure 1a via two-step solvothermal reactions. The SEM images of MoS2/ZnO on ITO display that the obtained MoS2 flakes were uniformly grown on the surface of ZnO nanorods with a length of 5 μm and a diameter of 1 μm (Figure 1b). Zn-, O-, Mo-, and S-based EDX mappings of MoS2/ZnO heterostructures are presented in Figure 1d−g, revealing that the four elements are homogeneously distributed throughout the surface. The morphology and core/shell structure of MoS2/ZnO were further investigated by TEM and HRTEM analysis. Panels h−j of Figure 1 demonstrate TEM images of MoS2 flakes grown on the top and sides of the ZnO nanorods, respectively. HRTEM images identify lattice fringes of 0.62 and 0.26 nm (Figure 1k), corresponding to the (002) hexagonal facets of MoS2 and the (002) facets of interplanar spacing of hexagonal ZnO, respectively.35−38 C

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Figure 3. (a) Photocurrent responses of ZnO (curves a0 and a1), MoS2 (curves b0 and b1), and MoS2/ZnO heterostructures (curves c0 and c1) modified ITO electrodes in the absence of (curves a0, b0, and c0) and presence of (curves a1, b1, and c1) 12.43 μmol L−1 PG. (b) Photocurrent responses of MoS2/ZnO heterostructures modified ITO electrodes upon different concentrations of PG. The inset is the corresponding linear calibration. (c) Photocurrent of 12 μmol L−1 PG, TBHQ, BHA, BHT, and VE on MoS2/ZnO heterostructures. (d) Photocurrrent response reproducibility for MoS2/ZnO modified ITO electrode in PBS buffer containing 12.43 μmol L−1 PG. The preceding photoelectrochemical experiments were applied at 0 V (vs Ag/AgCl) under 470 nm irradiation in 0.1 mol L−1 PBS (pH = 7.4).

Figure 2. (a) XPS spectrum of MoS2/ZnO heterostructures. (b) XRD patterns of ZnO and MoS2/ZnO heterostructures. (c) DRS spectra of ZnO and MoS2/ZnO. (d) EIS plot of ZnO and MoS2/ZnO modified ITO electrode in 1 mmol L−1 [Fe(CN)6]3‑/4‑ and 0.1 mol L−1 KCl aqueous solution.

sensor which is relevant to light absorption of photoactive materials.18 According to the UV−vis DRS in Figure 2c, light absorption is decreasing with increasing of the wavelength. Therefore, the wavelength makes a difference to photocurrent and response sensitivity. Hence, the working potential and wavelength of irradiation were initially optimized for the MoS2/ZnO-based PEC sensor. As shown in Supporting Information Figure S1a, with the exciting wavelength at 470 nm, upon addition of 147.1 μmol L−1 PG, the photocurrent increments sharply increased as the applied potential increased from −80 to 80 mV and tended to arrive at a maximum of 80 mV. Furthermore, the response was simultaneously decreased from 80 to 100 mV. Nevertheless, the photocurrent at 0 mV was 66.47% of the current value at 80 mV, which eventually demonstrates adequate sensitivity for the photoelectrochemical detection of PG. Moreover, the light source is another key factor for the photoelectrochemical sensor. As shown in Figure S1b, the photocurrent response drops to close to the baseline, with increase in illuminating wavelength from 365 to 630 nm. The highest photocurrent was observed under 365 nm irradiation, which was consistent with the strong light absorption of MoS2/ZnO (Figure 2c). Despite ultraviolet radiation bestowing the transducer with unsurpassed signal output, it is going to trigger new problems of serious interference due to coexisting substances in actual sample evaluation. Quantitative Detection of PG. Photocurrent response is of great importance to achieve sensitivity;40 hence a comparative test of composite heterostructure and pristine elements was carried out as shown in Figure 3a. The photoelectrochemical performance was investigated by irradiation under 470 nm. Interestingly, it was shown that MoS2/ ZnO heterostructures-based photoelectrochemical platform exhibited much higher photocurrent response (397.7 nA) in the analyte-free PBS solution as compared to pristine ZnO and MoS2. Photocurrent of heterostructure was dramatically increased to 1405 nA on addition of 12.43 μmol L−1 PG. A similar trend was observed in photocurrent responses of pristine ZnO (169.9 and 471.9 nA, respectively) and MoS2 (155.3 and 297.1 nA, respectively). As previously mentioned,

the growth of MoS2 onto ZnO tends to form a p−n heterojunction for efficient carriers separation and light absorption, which is consistent with the results of DRS and EIS, as shown in Figure 2c,d. The real-time photocurrent of MoS2/ZnO-modified electrode to a series of PG concentrations was recorded, as shown in Figure 3b. Conspicuously, the sensor presented a swift signal acquisition for PG when light was turned ON and passed through the solution followed by immediate turning OFF the power excitation in order to return to a steady state. It is noticeable that the photoresponse displayed the favorable linear relationships in three different concentration ranges, including 0.1249−12.43 (A), 12.43−147.1 (B), and 147.1− 1643 μmol L−1 (C). Moreover, the MoS2/ZnO-based PEC sensor allowed the detection of PG at a concentration as low as 0.1249 μmol L−1. Compared with other methods reported in previous studies for PG detection (Table S1), the MoS2/ZnObased PEC sensor exhibited excellent detection capacity toward PG with an evidently higher sensitivity and wider linear range, which can completely satisfy the real-sample detection needs.2 In order to precisely validate the selectivity of the MoS2/ ZnO-based photoelectrochemical platform, the same concentrations of PG, BHT, BHA, TBHQ, and VE were investigated. As shown in Figure 3c, the MoS2/ZnO-based PEC sensor manifested a moderate photocurrent increment on addition of 12 μmol L−1 PG, whereafter no intuitive photoeletrocatalytic behaviors were discovered when 12 μmol L−1 BHT, BHA, TBHQ, and VE were respectively introduced into the system. These results have successfully confirmed the selectivity of the MoS2/ZnO-based PEC sensor, which could be an excellent candidate for the real-time evaluation of PG in food. The stability is the key point for the sensor, and the main factors that affect the stability include photocorrosion and D

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than that of PG (0.446 V vs NHE). According to the redox potential ranking, TBHQ should have higher photocurrent than other antioxidants. However, the photocurrent of PG is higher than that of TBHQ (Figure 3c). Therefore, we further investigate the underlying mechanism of this phenomenon. As shown in Figure S3a, although low photocurrents of PG, TBHQ, BHA, and BHT were observed on the ZnO-based photoelectrochemical sensor, PG still showed higher photocurrent than that of other antioxidants. Moreover, BHT, BHA, TBHQ, VE, and PG all presented low photocurrents on the pristine MoS2 photocatalyst, and it is hard to discriminate PG from other antioxidants (Figure S3b). This demonstrates that the ZnO component plays a significant role in selective determination of PG. Recently, it has been reported that both oxygen atoms of the catechol species can form a five-atom chelate ring with the Ti(IV) surface site of TiO2.7,41 On the basis of these factors, in principle a similar mechanisim can also be proposed in the MoS2/ZnO-based PEC sensor for PG selective detection. As shown in Scheme 1, PG has three

poisoning of the photocatalyst from the production of analyte.18 Therefore, online monitoring of 12.43 μmol L−1 PG has been studied for longer duration as depicted in Figure 3d. It is noticeable that even after repeating the ON−OFF evaluation cycles for 30 times, the remaining signal proportion was still as high as 96.67%, which indicated excellent stability and reproducibility of the fabricated PEC sensor. Interference and Application in Practical Sample. As a matter of fact, there are commonly some commensal interferences in the detection samples. Hence, some possible interfering agents have been investigated in 147.13 μmol L−1 PG, as shown in Figure 4. In total, 1000 times of Na+, K+, Ca2+,

Scheme 1. Chemical Structures of Five Antioxidants and Proposed Mechanism of the MoS2/ZnO-Based Photoelectrochemical Sensor for the Detection of PG Figure 4. Interference of 1000 times of Na+, K+, Mg2+, and Ca2+ and 200 times of L-lysine, cysteine, L-histidine, L-threonine, glucose, methanol, and ethanol with photocurrent response of the MoS2/ZnObased on photoelectrochemical platform in the 0.1 mol L−1 PBS (pH = 7.4) containing 147.13 μmol L−1 PG.

and Mg2+ and 200 times of L-lysine, cysteine, L-histidine, Lthreonine, glucose, methanol, and ethanol were investigated. It was found that these interferences had little effect on the photoresponse of the sensing system. Moreover, as validation of PEC sensor for real-sample analysis determination of PG for two kinds of commercially available edible oil samples solubilized in ethanol was carried out. Samples containing PG at two different concentrations (1 and 50 μmol L−1) were analyzed, and the recovery values were calculated as listed in Table 1. The obtained recoveries ranged

adjacent hydroxyl groups which could bind with the Zn(II) surface site of ZnO to form a chelate structure resulting in a higher concentration of PG near MoS2/ZnO photocatalyst. The electrons and holes of MoS2/ZnO will be then separated and will generate photocurrent under irradiation. The electrons would transfer from MoS2 to ZnO, and the holes produced by MoS2 can in return efficiently oxidize PG. The appropriate conduction band formed in MoS2/ZnO nanocomposites efficiently enhance the electrons transfer from ZnO to the ITO electrode, which not only can decrease the recombination rate between the electron and hole but also can improve the sensitivity of the MoS2/ZnO-based photoelectrochemical sensor. It also provides a new method for design of photocatalyst with considering the composition and interaction with the detection molecule.

Table 1. Application of the Sensor for PG Determination in Real Samples samples PG added (μmol L−1) oil 1 oil 2

1 50 1 50

PG found (μmol L−1) PG recovery (%) 0.98 49.7 0.96 48.9

98 99.4 96 97.8

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CONCLUSIONS In this work, a promising label-free, visible-light-excited PEC sensor based on MoS2/ZnO heterostructure was successfully exploited for sensitive and selective determination of PG. The fabricated PEC sensor exhibited desirable performance in terms of high sensitivity, good stability, and excellent selectivity. MoS2/ZnO composites with proper band level between MoS2 and ZnO could make the photogenerated electrons and holes separate easily and result in great improvement of sensitivity. On the other hand, the chelate tendency of the Zn(II) surface site with adjacent oxygen atoms of PG with the ability to form a five-atom ring structure played significant roles for selective detection of PG. In addition, the

from 96% to 99.4%, indicating very good precision and accuracy. These results demonstrated that the photoelectrochemical method using the MoS2/ZnO heterostructured photocatalyst could be successfully used for the evaluation of PG in edible oil samples. Discussion of the Mechanism. Typically, molecules with proper redox properties get reduced by photoelectrons or oxidized by photogenerated holes in a photoelectrochemical platform. It is generally accepted that the photogenerated holes will react with species with lower redox potential on priority and trigger higher photocurrent. As shown in Figure S2, the redox potential of TBHQ is 0.368 V (vs NHE), which is lower E

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(12) Hao, N.; Hua, R.; Zhang, K.; Lu, J.; Wang, K. Anal. Chem. 2018, 90, 13207−13211. (13) Hao, N.; Hua, R.; Chen, S.; Zhang, Y.; Zhou, Z.; Qian, J.; Liu, Q.; Wang, K. Biosens. Bioelectron. 2018, 101, 14−20. (14) Ma, W.; Han, D.; Zhou, M.; Sun, H.; Wang, L.; Dong, X.; Niu, L. Chem. Sci. 2014, 5, 3946−3951. (15) Wang, L.; Han, D.; Ni, S.; Ma, W.; Wang, W.; Niu, L. Chem. Sci. 2015, 6, 6632−6638. (16) Gao, X.; Wu, H.; Zheng, L.; Zhong, Y.; Hu, Y.; Lou, X. Angew. Chem., Int. Ed. 2014, 53, 5917−5921. (17) Bhachu, D.; Moniz, S.; Sathasivam, S.; Scanlon, D.; Walsh, A.; Bawaked, S.; Mokhtar, M.; Obaid, A.; Parkin, I.; Tang, J.; Carmalt, C. Chem. Sci. 2016, 7, 4832−4841. (18) Wang, L.; Liu, Z.; Wang, D.; Ni, S.; Han, D.; Wang, W.; Niu, Li. Biosens. Bioelectron. 2017, 94, 107−114. (19) Jiang, D.; Du, X.; Zhou, L.; Li, H.; Wang, K. Anal. Chem. 2017, 89, 4525−4531. (20) Zhang, Y.; Ge, L.; Li, M.; Yan, M.; Ge, S.; Yu, J.; Song, X.; Cao, B. Chem. Commun. 2014, 50, 1417−1419. (21) Chen, L.; Xue, F.; Li, X.; Huang, X.; Wang, L.; Kou, J.; Wang, Z. ACS Nano 2016, 10, 1546−1551. (22) Yang, T.; Chen, M.; Kong, Q.; Luo, X.; Jiao, K. Biosens. Bioelectron. 2017, 89, 538−544. (23) Xue, F.; Chen, L.; Chen, J.; Liu, J.; Wang, L.; Chen, M.; Pang, Y.; Yang, X.; Gao, G.; Zhai, J.; Wang, Z. Adv. Mater. 2016, 28, 3391− 3398. (24) Wang, J.; Yang, Z.; Gao, X.; Yao, W.; Wei, W.; Chen, X.; Zong, R.; Zhu, Y. Appl. Catal., B 2017, 217, 169−180. (25) Guo, L.; Yang, Z.; Marcus, K.; Li, Z.; Luo, B.; Zhou, L.; Wang, X.; Du, Y.; Yang, Y. Energy Environ. Sci. 2018, 11, 106−114. (26) Wang, X.; Ma, W.; Ge, T.; Yang, T.; Jiao, K. Electrochim. Acta 2016, 190, 1025−1031. (27) Jiang, D.; Du, X.; Liu, Q.; Hao, N.; Wang, K. Biosens. Bioelectron. 2019, 126, 463−469. (28) Tang, R.; Yin, R.; Zhou, S.; Ge, T.; Yuan, Z.; Zhang, L.; Yin, L. J. Mater. Chem. A 2017, 5, 4962−4971. (29) Gomathi, P.; Sahatiya, P.; Badhulika, S. Adv. Funct. Mater. 2017, 27, 1701611−1701619. (30) Zhao, M.; Chen, A.; Huang, D.; Chai, Y.; Zhuo, Y.; Yuan, R. Anal. Chem. 2017, 89, 8335−8342. (31) Yang, T.; Chen, M.; Kong, Q.; Luo, X.; Jiao, K. Biosens. Bioelectron. 2017, 89, 538−544. (32) Yang, T.; Chen, H.; Jing, C.; Luo, S.; Li, W.; Jiao, K. Sens. Actuators, B 2017, 249, 451−457. (33) Yang, T.; Cui, Y.; Yu, R.; Luo, S.; Li, W.; Jiao, K.; Chen, M. ACS Sustainable Chem. Eng. 2017, 5, 1332−1338. (34) Miao, L.; Zhang, H.; Zhu, Y.; Yang, Y.; Li, Q.; Li, J. J. Mater. Sci.: Mater. Electron. 2012, 23, 1887−1890. (35) Zhang, N.; Gan, S.; Wu, T.; Ma, W.; Han, D.; Niu, L. ACS Appl. Mater. Interfaces 2015, 7, 12193−12202. (36) Jian, W.; Cheng, X.; Huang, Y.; You, Y.; Zhou, R.; Sun, T.; Xu, J. Chem. Eng. J. 2017, 328, 474−483. (37) Kayaci, F.; Vempati, S.; Ozgit-Akgun, C.; Biyikli, N.; Uyar, T. Appl. Catal., B 2014, 156−157, 173−183. (38) Huang, Y.; Miao, Y.; Zhang, L.; Tjiu, W.; Pan, J.; Liu, T. Nanoscale 2014, 6, 10673−10679. (39) Wang, L.; Ma, W.; Gan, S.; Han, D.; Zhang, Q.; Niu, L. Anal. Chem. 2014, 86, 10171−10178. (40) Yang, R.; Zou, K.; Li, Y.; Meng, L.; Zhang, X.; Chen, J. Anal. Chem. 2018, 90, 9480−9486. (41) Liu, L.; Li, S.; Cheng, H.; Diebold, U.; Selloni, A. J. Am. Chem. Soc. 2011, 133, 7816−7823.

PEC sensor was applied for PG evaluation in different commercially available edible oils. Furthermore, we hope to develop a method such as multichannel sensors that can detect a variety of antioxidants, types, and components on the basis of this single channel PEC sensor. The fabricated MoS2/ZnOheterostructure-based PEC sensor opens a new door for the development of monitoring food quality and safety to reduce the risk of overuse of PG in foods.

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ASSOCIATED CONTENT

S Supporting Information *

The Supporting Information is available free of charge on the ACS Publications website at DOI: 10.1021/acs.analchem.9b01889.

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Effects of work potential and wavelength on photocurrent response; cyclic voltammograms and redox potentials; comparison of some previous reports for the determination of PG with our work (PDF)

AUTHOR INFORMATION

Corresponding Authors

*(D.H.) E-mail: [email protected]. Fax: +86-431-85262800. Tel.: +86-431-85262425. *(L.H.) E-mail: [email protected]. ORCID

Mian Hasnain Nawaz: 0000-0002-6648-0778 Lipeng Han: 0000-0001-9077-922X Dongxue Han: 0000-0002-7343-2221 Li Niu: 0000-0003-3652-2903 Notes

The authors declare no competing financial interest.

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ACKNOWLEDGMENTS We are most grateful to NSFC, China (Grant Nos. 21622509, 21527806, 21627809, and 21727815), Department of Science and Techniques of Jilin Province (Grant Nos. 20160201008GX and 20170101183JC), and Science and Technology Bureau of Changchun (Grant No. 15SS05)

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REFERENCES

(1) Cui, M.; Huang, J.; Wang, Y.; Wu, Y.; Luo, X. Biosens. Bioelectron. 2015, 68, 563−569. (2) Andre, C.; Castanheira, I.; Cruz, J.; Paseiro, P.; Sanches-Silva, A. Trends Food Sci. Technol. 2010, 21, 229−246. (3) Vikraman, A.; Rasheed, Z.; Rajith, L.; Lonappan, L.; Krishnapillai, K. Food Anal. Methods 2013, 6, 775−780. (4) Kim, J.; Choi, S.; Shin, G.; Lee, J.; Kang, S.; Lee, K.; Lim, H.; Kang, T.; Lee, O. Food Chem. 2016, 213, 19−25. (5) Cacho, J.; Campillo, N.; Viñas, P.; Hernández-Córdoba, M. Food Chem. 2016, 200, 249−254. (6) Dai, Y.; Li, X.; Fan, L.; Lu, X.; Kan, X. Biosens. Bioelectron. 2016, 86, 741−747. (7) Ma, W.; Wang, L.; Zhang, N.; Han, D.; Dong, X.; Niu, L. Anal. Chem. 2015, 87, 4844−4850. (8) Wang, Q.; Ruan, Y.; Zhao, W.; Lin, P.; Xu, J.; Chen, H. Anal. Chem. 2018, 90, 3759−3765. (9) Yu, L.; Zhu, Y.; Liu, Y.; Qu, P.; Xu, M.; Shen, Q.; Zhao, W. Anal. Chem. 2018, 90, 10803−10811. (10) Kong, Q.; Cui, K.; Zhang, L.; Wang, Y.; Sun, J.; Ge, S.; Zhang, Y.; Yu, J. Anal. Chem. 2018, 90, 11297−11304. (11) Xin, Y.; Li, Z.; Zhang, Z. Chem. Commun. 2015, 51, 15498− 15501. F

DOI: 10.1021/acs.analchem.9b01889 Anal. Chem. XXXX, XXX, XXX−XXX