Science Daily June 30, 2022
Laser-induced thermal voxels (LITV) offer a facile platform to directly integrate nanocrystalline metal oxide and mixed metal oxide materials onto heating platforms, with access to a wide variety of compositions and morphologies including many transition metals and noble metals. Researchers at Pennsylvania State University combined laser writing and responsive sensor technologies to fabricate the first highly customizable microscale gas sensing devices. They investigated the sensing performance of a representative set of n-type and p-type LITV-deposited metal oxides and their mixtures (CuO, NiO, CuO/ZnO, and Fe2O3/Pt) in response to reducing and oxidizing gases (H2S, NO2, NH3, ethanol, and acetone). These materials show a broad range of sensitivities and notably a strong response of NiO to ethanol and acetone, along with a 5- to 20-fold sensitivity enhancement for CuO/ZnO to all gases measured over pure CuO, highlighting the opportunities of LITV for the creation of mixed-material microscale sensors. This finding supports other reports that the creation of mixed oxide systems can lead to significant increases in sensor response and demonstrates the efficacy of the laser-induced thermal voxel technique for mixed-oxide gas sensor fabrication…read more. TECHNICAL ARTICLE
Abstract. Credit: CS Appl. Mater. Interfaces 2022, 14, 24, 28163–28173, June 10, 2022