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Abstract: A new hydrogen peroxide detection sensitive material, boron doped carbonized ZIF‐67@graphene (Co‐N/C@G‐B) is synthesized through pyrolysis of a sandwich‐like ZIF‐67 coating graphene material. After doping boron atoms by using chemical vapor deposition method, new active sites such as Co2B and BNC bonds are created, and mesopores are significantly increased. Most importantly, this Co‐N/C@G‐B material is found to exhibit excellent performance as an enzyme‐free biosensor for detecting hydrogen peroxide with a very wide detection range (from 0.5 × 10−6 to 60 × 10−3 m), a low detection limit (0.19 × 10−6 m), and a rapid response time (≈3 s). The prepared biosensor also shows strong anti‐interference ability in the complex working occasions. Furthermore, for real application of the materials, an electronic device of biosensor is developed by using technologies of screen printing electrode, integrated circuit, 3D printed shell, and custom‐developed program, which shows high sensitivity and portability to detect hydrogen peroxide. Such device paves a way for further practical application of advanced materials in commercial scale. [ABSTRACT FROM AUTHOR]

A sensitive and noble amperometric horseradish peroxidase (HRP) biosensor is fabricated via the deposition of gold nanoparticles (AuNPs) onto a three-dimensional (3D) porous carbonized chicken eggshell membrane (CESM). Due to the synergistic effects of the unique porous carbon architecture and well-distributed AuNPs, the enzyme-modified electrode shows an excellent electrochemical redox behavior. Compared with bare glass carbon electrode (GCE), the cathodic peak current of the enzymatic electrode increases 12.6 times at a formal potential of −100mV (vs. SCE) and charge-transfer resistance decreases 62.8%. Additionally, the AuNPs-CESM electrode exhibits a good biocompatibility, which effectively retains its bioactivity with a surface coverage of HRP 6.39×10−9mol cm−2 (752 times higher than the theoretical monolayer coverage of HRP). Furthermore, the HRP-AuNPs-CESM-GCE electrode, as a biosensor for H2O2 detection, has a good accuracy and high sensitivity with the linear range of 0.01–2.7 mM H2O2and the detection limit of 3μM H2O2(S/N = 3). [ABSTRACT FROM AUTHOR]

S-doped graphene has attracted extensive interest in recent years due to its high catalytic activity. However, most of the previously reported S-doped graphene materials present diverse types of S-bonding configurations, it is hard to distinguish which configuration is mainly responsible for the catalytic activity. Here, homogeneous thiophene S-doped graphene can be synthesized through solid-state reaction between graphene oxide and sulfate, and the doping amount can be easily tuned by the sulfate dosage. More importantly, abundant micropores and some mesopores are formed in the surface of graphene sheets during S-doping. Due to its high S-loading mass, thiophenic sulfur species and unique porous structure, S-doped graphene shows high electrocatalytic activity toward the redox reaction of dopamine, such as high selectivity, high sensitivity and low detection limit (3.94 μM μA −1 , 1.5 × 10 −8 M at S / N = 3). [ABSTRACT FROM AUTHOR]