{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,4,7]],"date-time":"2026-04-07T16:23:33Z","timestamp":1775579013899,"version":"3.50.1"},"reference-count":28,"publisher":"MDPI AG","issue":"12","license":[{"start":{"date-parts":[[2014,12,17]],"date-time":"2014-12-17T00:00:00Z","timestamp":1418774400000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"funder":[{"name":"Ministry of Education, Malaysia","award":["UM.C\/625\/1\/HIR\/MOHE\/SCI\/29\/01"],"award-info":[{"award-number":["UM.C\/625\/1\/HIR\/MOHE\/SCI\/29\/01"]}]},{"DOI":"10.13039\/501100004386","name":"University of Malaya","doi-asserted-by":"publisher","award":["RU002\/2013"],"award-info":[{"award-number":["RU002\/2013"]}],"id":[{"id":"10.13039\/501100004386","id-type":"DOI","asserted-by":"publisher"}]},{"DOI":"10.13039\/501100004386","name":"University of Malaya","doi-asserted-by":"publisher","award":["RP019-2012B"],"award-info":[{"award-number":["RP019-2012B"]}],"id":[{"id":"10.13039\/501100004386","id-type":"DOI","asserted-by":"publisher"}]}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Sensors"],"abstract":"<jats:p>The optical characteristics of graphene oxide (GO) were explored to design and fabricate a GO-based optical humidity sensor. GO film was coated onto a SU8 polymer channel waveguide using the drop-casting technique. The proposed sensor shows a high  TE-mode absorption at 1550 nm. Due to the dependence of the dielectric properties of the GO film on water content, this high TE-mode absorption decreases when the ambient relative humidity increases. The proposed sensor shows a rapid response (&lt;1 s) to periodically interrupted humid air flow. The transmission of the proposed sensor shows a linear response of 0.553 dB\/% RH in the range of 60% to 100% RH.<\/jats:p>","DOI":"10.3390\/s141224329","type":"journal-article","created":{"date-parts":[[2014,12,17]],"date-time":"2014-12-17T10:19:28Z","timestamp":1418811568000},"page":"24329-24337","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":71,"title":["All-Optical Graphene Oxide Humidity Sensors"],"prefix":"10.3390","volume":"14","author":[{"given":"Weng","family":"Lim","sequence":"first","affiliation":[{"name":"Photonics Research Centre, University of Malaya, Kuala Lumpur 50603, Malaysia"},{"name":"Department of Physics, Faculty of Science, University of Malaya, Kuala Lumpur 50603, Malaysia"}]},{"given":"Yuen","family":"Yap","sequence":"additional","affiliation":[{"name":"Photonics Research Centre, University of Malaya, Kuala Lumpur 50603, Malaysia"},{"name":"Department of Physics, Faculty of Science, University of Malaya, Kuala Lumpur 50603, Malaysia"},{"name":"Centre for Foundation Studies, SEGi University, Kota Damansara 47810, Selangor, Malaysia"}]},{"given":"Wu","family":"Chong","sequence":"additional","affiliation":[{"name":"Photonics Research Centre, University of Malaya, Kuala Lumpur 50603, Malaysia"},{"name":"Department of Physics, Faculty of Science, University of Malaya, Kuala Lumpur 50603, Malaysia"}]},{"given":"Harith","family":"Ahmad","sequence":"additional","affiliation":[{"name":"Photonics Research Centre, University of Malaya, Kuala Lumpur 50603, Malaysia"},{"name":"Department of Physics, Faculty of Science, University of Malaya, Kuala Lumpur 50603, Malaysia"}]}],"member":"1968","published-online":{"date-parts":[[2014,12,17]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","unstructured":"Bi, H., Yin, K., Xie, X., Ji, J., Wan, S., Sun, L., Terrones, M., and Dresselhaus, M.S. 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