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Novel two-dimensional Ti 3 C 2 MXene nanosheets were successfully prepared by etching Al from Ti 3 AlC 2 in LiF/HCl system. In order to further improve the dispersing property and electrical conductivity of Ti 3 C 2 nanosheets, Ti 3 C 2 /graphene oxide (Ti 3 C 2 -GO) nanocomposites were synthesized and applied for the fabrication of inkjet-printed hydrogen peroxide (H 2 O 2 ) sensor. The results of electrochemical characterization show that the prepared sensor maintains the biological activity of hemoglobin (Hb) and can be applied to the practical detection. The printed sensors display a dynamic range from 2 μM to 1 mM and a detection limit of 1.95 μM with a high sensitivity and excellent selectivity for H 2 O 2 determination. Therefore, the printable Ti 3 C 2 -GO nanocomposites are an excellent sensing platform for electrochemical determination.

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A label-free sensing platform is developed based on switching the structure of aptamer for highly sensitive and selective fluorescence detection of ochratoxin A (OTA). OTA induces the structure of aptamer, transforms into G-quadruplex and produces strong fluorescence in the presence of zinc(II)-protoporphyrin IX probe due to the specific bind to G-quadruplex. The simple method exhibits high sensitivity towards OTA with a detection limit of 0.03 nM and excellent selectivity over other mycotoxins. In addition, the successful detection of OTA in real samples represents a promising application in food safety.

This work describes the fabrication of high‐performance all‐solid‐state supercapacitors based on covalently‐anchored reduced graphene oxide (RGO)@polyaniline (PANI) composites via an inkjet printing method. Morphological and chemical characterization data show that PANI nanoparticles are immobilized on graphene oxide (GO) nanosheets via covalent bonds. Sandwich‐structured and interdigitated supercapacitors are fabricated by printing the as‐prepared GO@PANI composites on flexible substrates, followed by a chemical reduction. The devices display high volumetric capacitances (258.5 F cm−3 at 1 mV s−1 for sandwich‐structured ones and 554 F cm−3 at 1 mV s−1 for interdigitated ones) and excellent cycling retention (2000 cycles >90%). Moreover, at the bending state, there are no significant changes on the device capacitances, indicating their great flexibility. The high‐performance devices can be further designed to produce special geometries and patterns. The work may provide a novel strategy to fabricate RGO@PANI composite‐based supercapacitors, which allows the end users to precisely deposit active materials according to their designs, for miniature and wearable electronics.

In this work, we successfully fabricate a rapid, sensitive sensor for the detection of superoxide anions O2˙− based on graphene/DNA/Mn3(PO4)2 biomimetic enzyme.

Carbon nanofiber/manganese oxide (CNF‐MnO) hybrid nanofibers are synthesized by calcination of potassium permanganate (KMnO4) loaded bacterial cellulose (BC) hydrogels. The chemical structure, morphology, performance, and application of CNF‐MnO aerogels are characterized and studied. The results revealed that MnO nanoparticles are uniformly deposited on the surface of CNF which derived from BC hydrogels. An amperometric superoxide anions (O2•−) sensor is fabricated by the immobilization of the CNF‐MnO aerogels on a glassy carbon electrode, which displays a linear amperometric response with a high sensitivity of 76.2 µA cm−2 × 10−3m−1 and a low detection limit of 1.2 × 10−9m in the concentration range of 5.0 × 10−9m – 2.5 × 10−6m. The successful detection of O2•− released from cancer cells verifies the potential application in biomedical field.