Compared with traditional "lock-key mode" biosensors, a sensor array consists of a series of sensing elements based on intermolecular interactions (typically hydrogen bonds, van der Waals forces, and electrostatic interactions). At the same time, sensor arrays also have the advantages of fast response, high sensitivity, low energy consumption, low cost, rich output signals, and imageability, which have attracted widespread attention from researchers. Nanozymes are nanomaterials which own enzyme-like properties. Because of the adjustable activity, high stability, and cost effectiveness of nanozymes, they are potential candidates for construction of sensor arrays to output different signals from analytes through the chemoresponse of colorants, which solves the shortcomings of traditional sensors that they cannot support multiple detection and lack universality. Recently, a sensor array based on nanozymes as nonspecific recognition receptors has attracted much more attention from researchers and has been applied to precise recognition of proteins, bacteria, and heavy metals. In this perspective, attention is given to nanozymes and the regulation of their enzyme-like activity. Particularly, the building principles and methods for sensor arrays based on nanozymes are analyzed, and the applications are summarized. Finally, the approaches to overcome the challenges and perspectives are also presented and analyzed for facilitating further research and development of nanozyme sensor arrays. This perspective should be helpful for gaining insight into research ideas within the field of nanozyme sensor arrays.

Aqueous Zn metal batteries are attracting tremendous interest as promising energy storage systems due to their intrinsic safety and cost-effectiveness. Nevertheless, the reversibility of Zn metal anodes (ZMAs) is hindered by water-induced parasitic reactions and dendrite growth. Herein, a novel hydrated eutectic electrolyte (HEE) consisting of Zn(BF4)2xH2O and sulfolane (SL) is developed to prevent the side reactions and achieve the outstanding cyclability of ZMAs. The strong coordination between Zn2+ and SL triggers the eutectic feature, enabling the low-temperature availability of HEEs. The restriction of BF4- hydrolysis in the eutectic system can realize favorable compatibility between Zn(BF4)2-based electrolyte and ZMAs. Besides, the newly-established solvation structure with the participation of SL, H2O, and BF4-, can induce in situ formation of desirable SEI with gradient structure consisting of B,O-rich species, ZnS, and ZnF2, to offer satisfactory protection toward ZMAs. Consequently, the HEE allows the Zn||Zn symmetric cell to cycle over 1650 h at 2 mA cm-2 and 1 mA h cm-2. Moreover, the Zn||NH4V4O10 full batteries can deliver a prolonged lifespan for 1000 cycles with a high capacity retention of 83.4%. This work represents a feasible approach toward the elaborate design of advanced electrolyte systems for next-generation batteries. A novel eutectic electrolyte comprising hydrated Zn(BF4)2 and sulfolane delivers a well-regulated solvation structure and enables the in situ formation of a unique solid electrolyte interphase with gradient structure, realizing the outstanding reversibility of Zn metal anodes and ultralong cyclability of as-fabricated Zn metal batteries. image

Two-dimensional (2D) porous carbon nanosheets loaded with bimetallic oxide nanospheres are expected to be very attractive electrocatalysts. In this work, we constructed ordered mesoporous nitrogen-rich carbon on the surface of ultrathin-reduced graphene oxide (rGO) using the self-assembly of block polymers and compared the effect of pore structure on the sensing performance. The rGO wrapped by N-doped ordered porous carbon possesses a large specific surface area of 784.9 m2/g. The composite with NiFe2O4 nanospheres with rough surfaces effectively prevented the interlayer accumulation of mNPC@rGO. Meanwhile, the multivalent form of metal elements in NiFe2O4 facilitates the redox reaction. These distinct advantages combine to create an active surface that strongly binds to chlorogenic acid molecules (CGA). Importantly, we have computationally analyzed the reaction mechanism of mNPC@rGO/NiFe2O4 electrocatalytic CGA molecules by density functional theory. In the best case, the mNPC@rGO/NiFe2O4/GCE sensor has a limit of detection (LOD) as low as 2 x 10-11 M and a wide linear range (1 x 10-10-2 x 10-5 M). The sensor displays a remarkable level of selective response to CGA in the presence of other co-interfering species. Furthermore, it has superb repeatability and reproducibility for CGA. The sensor has shown outstanding recovery (95.9%-104.9%) in the practical viability of detecting CGA in food, natural products, and biological samples. This work not only provides a new candidate for the accurate detection of CGA, but also provides insight into the exploration of advanced sensing materials.

A rapid analytical method has been developed for the determination of polybrominated diphenyl ethers (PBDEs) in vegetables. PBDEs were determined by gas chromatography with negative chemical ionization mass spectrometric detection in the selected ion monitoring mode (GC-NCI-MS-SIM). The method detection limits (MDLs) were evaluated as 5 times the signal/noise (S/N) ratio in the GC/MS peaks by analyzing spiked vegetable samples at 2 - 50 ng/g. The minimum limits of instrument detection for this method were 0.28 - 0.78 pg for tri- to hepta-BDEs and 3.60 pg for deca-BDEs respectively. The minimum limit of method detection for tri to hepta-BDEs was 28 pg/g dry weight and 360 pg/g dry weight for deca-BDEs. In the examined vegetable samples, BDE-209 was the prominent congener detected in most cases, followed by BDE-47, BDE-71. The total concentration of PBDEs was in the range of 53.38 - 2884.02ng/g dry weight.

A study on degradation of 2,4-dichlorophenol in aqueous solution using 172nm excimer UV source is reported. Degradation products were analyze by Gas chromatography time-of-flight mass spectrometry. The experiment results show that a low concentration (1 mg/L) and a high concentration (10mg/L) 2,4-dichlorophenol are directly irradiated separately. By GC-TOFMS technique analysis, the, results indicate that under the irradiation the 1mg/L 2,4-dichlorophenol is extremely unstable and decompose completely in 1.5 minutes. However, after 10 minutes irradiation on the 10 mg/L 2,4-dichlorophenol, the degradation products of 2-chlorophenol, phenol, benzenediol and benzoquinone are detected. The possible process of the degradation 2,4-dichlorophenol by excimer UV resource is presented.

The study of mineral components in respirable particles (particulate matter with diameter less than 10 μm, PM10) in ambient air is important in understanding and improving air quality. In this study, PM10 samples were collected in various areas around Beijing during 2002∼2003, including an urban setting, a satellite city and a rural area. The mineralogical composition of these PM10 samples was studied by X-ray diffraction (XRD), environmental scanning electron microscopy / and energy-dispersive X-ray analyzer (ESEM/EDX). The results indicated that mineral composition of PM10 in different seasons and in different region varied significantly. Mineral mass concentration in Beijing PM10 reached the highest percentage in the spring and fell to the lowest level in the autumn. The minerals in the spring PM10 were dominated by clay minerals and quartz, followed by plagioclase, K-feldspar, calcite, dolomite, hematite, pyrite, magnesite, gypsum and laumontite as well as some unidentified materials. Fewer mineral types were collected in summer, however some new components, including K(NH4)Ca(SO4)2·H2O, NH4Cl and As2O3·SO3 were noted to be present, suggesting that atmospheric chemical reaction in Beijing air were more active in summer than in other seasons. Mineral components in Beijing urban air were at a higher percentage with fewer phases than that in satellite city air. In conclusion, there was considerable variation in mineral components in PM10 samples collected in different seasons and areas, which reflects the related air quality of sampling areas.

A novel extractant, N,N′-dilauroylpiperazine (DLPEZ), was synthesized for the first time. The extraction of uranium(VI) with the novel extractant in carbon tetrachloride from aqueous nitric acid media has been studied. The dependence of extraction distribution ratio on the concentration of aqueous nitric acid, extractant, salting-out agent and temperature was investigated and the enthalpy of the extraction was determined.