Lin Yu,Jingyuan Liu,Wenyan Yin,Jing Yu,Rongrong Chen,Dalei Song,Qi Liu,Rumin Li,Jun Wang
Ionic liquids are promising electrolytes for electrochemical gas sensors that have unique physicochemical properties such as negligible vapor pressure and high thermal stability. The modification of ionic liquid (IL) by combining metal oxide with reduced graphene oxide (rGO) is an effective method to improve its gas-sensing properties. In this study, the mesoporous structure of NiCo 2 O 4 /rGO is synthesized by simple one-step method, and the ionic liquid 1-butyl-3-methylimidazolium hexafluorophosphate ([BMIM][PF 6 ]) is mixed with it to form the composite material NiCo 2 O 4 /rGO/[BMIM][PF 6 ]. Electrochemical test results indicate that the three electrolytes exhibit response current and long-term stability in the oxygen environment. The oxygen sensor based on NiCo 2 O 4 /rGO/[BMIM][PF 6 ] significantly improves the response current and working stability of pure ionic liquid. The sensitivity of the sensor is 0.1087 μA/[%O 2 ], and the linear regression coefficient of the reduction peak current calibration curve is 0.9995. After continuous cyclic voltammetry , the reduction peak current remains at 90% of the initial current value. The interaction of IL and NiCo 2 O 4 /rGO significantly enhances electrochemical oxygen sensing performance.
Yuanmeng Zhao,Yunhao Jiang,Yan Mo,Yueming Zhai,Juejing Liu,Andrew C. Strzelecki,Xiaofeng Guo,Changsheng Shan
It is critical to develop high-performance electrocatalyst for electrochemical nonenzymatic glucose sensing. In this work, a single-atom Pt supported on Cu@CuO core–shell nanowires (Pt 1 /Cu@CuO NWs) for electrochemical nonenzymatic glucose sensor is designed. Pt 1 /Cu@CuO NWs exhibit excellent electrocatalytic oxidation toward glucose with 70 mV lower onset potential (0.131 V) and 2.4 times higher response current than Cu NWs. Sensors fabricated using Pt 1 /Cu@CuO NWs also show high sensitivity (852.163 µA mM −1 cm −2 ), low detection limit (3.6 µM), wide linear range (0.01–5.18 µM), excellent selectivity, and great long-term stability. The outstanding sensing performance of Pt 1 /Cu@CuO NWs, investigated by experiments and density functional theory (DFT) calculations, is attributed to the synergistic effect between Pt single atoms and Cu@CuO core–shell nanowires that generates strong binding energy of glucose on the nanowires. The work provides a new pathway for exploring highly active SACs for electrochemical nonenzymatic glucose sensor.
Binghuan Zhang,Liyuan Wang,Shwu-Jen Chang,Yanzhen Jing,Tianyi Sun,Ziang Lei,Ching-Jung Chen,Jen-Tsai Liu
Wearable glucose sensors have attracted significant attention for enabling non-invasive blood glucose measurement without discomfort and risk of infection. However, it is a challenge to simultaneously realize wearable adaptability, biodegradability, and excellent sensing performance. Herein, a cellulose paper-based non-invasive biosensor relying on reverse iontophoresis was designed to detect glucose in interstitial fluid (ISF), and two different enzyme immobilization strategies have been compared. The results showed inkjet-printed cellulose paper-based biosensor (IPB) performances better than the drop-coated cellulose paper-based biosensor (DPB). IPB has twice response current more than DPB in detection range (0–10 mM). In sensitivity, IPB is 1.170 μA/mM three times higher than the DPB (0.376 μA/mM). Besides, IPB's electron-transfer resistance (Rct) is 7.27 kΩ smaller than DPB (Rct = 10.51 kΩ) about 30 %. More importantly, IPB exhibited a good reproducibility (RSD, 4.82 %), which was much less than DPB (RSD, 18.35 %). Furthermore, the IPB realizes noninvasive continuous glucose monitoring over 6 h in volunteer experiments with great analytical performance comparable to commercial devices (Pearson correlation 0.732). Cellulose paper-based glucose sensors with inkjet printing provide non-invasive access to statistically significant diagnostic information, simple and cost-effective, which promotes the application of flexible, wearable, degradable bioelectrodes in continuous glucose monitoring at home, providing a concept for full integration in a compact and portable way in the future.
危险品化学品经营许可证（带存储）