TY - JOUR A1 - Wang, Bei A1 - Sun, Ling A1 - Schneider-Ramelow, Martin A1 - Lang, Klaus-Dieter A1 - Ngo, Ha-Duong ED - Yang, Yi ED - Zhang, Yi ED - Xiao, Limin ED - El Abed, Abdel I. ED - Xiao, Shumin ED - Zhang, Xuming T1 - Recent Advances and Challenges of Nanomaterials-Based Hydrogen Sensors JF - Micromachines N2 - Safety is a crucial issue in hydrogen energy applications due to the unique properties of hydrogen. Accordingly, a suitable hydrogen sensor for leakage detection must have at least high sensitivity and selectivity, rapid response/recovery, low power consumption and stable functionality, which requires further improvements on the available hydrogen sensors. In recent years, the mature development of nanomaterials engineering technologies, which facilitate the synthesis and modification of various materials, has opened up many possibilities for improving hydrogen sensing performance. Current research of hydrogen detection sensors based on both conservational and innovative materials are introduced in this review. This work mainly focuses on three material categories, i.e., transition metals, metal oxide semiconductors, and graphene and its derivatives. Different hydrogen sensing mechanisms, such as resistive, capacitive, optical and surface acoustic wave-based sensors, are also presented, and their sensing performances and influence based on different nanostructures and material combinations are compared and discussed, respectively. This review is concluded with a brief outlook and future development trends. KW - Wasserstoff KW - hydrogen safety KW - hydrogen sensor KW - transition metals KW - catalytic sensing KW - micro and nanosensors KW - metal oxide semiconductors KW - graphene KW - graphene oxide KW - reduced graphene oxide KW - Mikrosensor KW - Graphen KW - Graphenoxid KW - Halbleiter Y1 - 2021 U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:kobv:523-15302 SN - 2072-666X VL - 12 IS - 11 SP - 1 EP - 56 PB - MDPI ER - TY - JOUR A1 - Wang, Bei A1 - Baeuscher, Manuel A1 - Hu, Xiaodong A1 - Woehrmann, Markus A1 - Becker, Katharina A1 - Juergensen, Nils A1 - Hubl, Moritz A1 - Mackowiak, Piotr A1 - Schneider-Ramelow, Martin A1 - Lang, Klaus-Dieter A1 - Ngo, Ha-Duong T1 - Development and Characterization of a Novel Low-Cost Water-Level and Water Quality Monitoring Sensor by Using Enhanced Screen Printing Technology with PEDOT:PSS JF - Micromachines N2 - A novel capacitive sensor for measuring the water-level and monitoring the water quality has been developed in this work by using an enhanced screen printing technology. A commonly used environment-friendly conductive polymer poly(3,4-ethylenedioxythiophene):poly (styrenesulfonate) (PEDOT:PSS) for conductive sensors has a limited conductivity due to its high sheet resistance. A physical treatment performed during the printing process has reduced the sheet resistance of printed PEDOT:PSS on polyethylenterephthalat (PET) substrate from 264.39 Ω/sq to 23.44 Ω/sq. The adhesion bonding force between printed PEDOT:PSS and the substrate PET is increased by using chemical treatment and tested using a newly designed adhesive peeling force test. Using the economical conductive ink PEDOT:PSS with this new physical treatment, our capacitive sensors are cost-efficient and have a sensitivity of up to 1.25 pF/mm. KW - water-level sensor KW - water quality monitoring KW - adhesive peeling force test KW - screen printing KW - poly(3,4-ethylenedioxythiophene):poly(styrenesulfonate) (PEDOT:PSS) KW - conductive polymer KW - capacitive sensor Y1 - 2020 U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:kobv:523-3789 SN - 2072-666X VL - 11 IS - 5 PB - MDPI ER -