Direct Laser Writing of Microscale Metal Oxide Gas Sensors from Liquid Precursors

• DOI: 10.1021/acsami.2c03561
• Publication Date: 2022-06-10T12:22:41Z
• Authors: Alexander C. Cast...; Ning Yi; Bowen Li; Jiang Zhao; Han Li; Yuyan Gao; Nabila N. Nova; Naveen Tiwari; Lauren D. Zarzar; Huanyu Cheng
• Keywords: Microscale chemistry; Oxidizing agent; Non-blocking I/O; Nanomaterials

Fabrication and processing approaches that facilitate the ease of patterning integration nanomaterials into sensor platforms are significant utility interest. In this work, we report use laser-induced thermal voxels (LITV) to fabricate microscale, planar gas sensors directly from solutions metal salts. LITV offers a facile platform integrate nanocrystalline oxide mixed materials onto heating platforms, with access wide variety compositions morphologies including many transition metals noble metals. The unique synthesis flexibility enable fabrication chemically spatially tailorable microscale sensing devices. We investigate performance representative set n-type p-type LITV-deposited oxides their mixtures (CuO, NiO, CuO/ZnO, Fe2O3/Pt) in response reducing oxidizing gases (H2S, NO2, NH3, ethanol, acetone). These show broad range sensitivities notably strong NiO ethanol acetone (407 301% R/R0 at 250 °C, respectively), along 5- 20-fold sensitivity enhancement for CuO/ZnO all measured over pure CuO, highlighting opportunities creation mixed-material sensors.