Abstract
An H2S sensor based on randomly distributed nano p-n junction between CuO and WO3 has been demonstrated. Modification with CuO resulted in enhanced response kinetics towards H2S with high selectivity. CuO modified WO3 thin films corresponding to 2.25 at% of Cu exhibited a sensor response of 534 in comparison to that of pure WO 3 thin films that exhibited a sensor response of 21 towards 10 ppm of H2S at an operating temperature of 300 C. This enhanced response kinetics has been attributed to the formation of random nano p-n junctions distributed over the surface of the sensor film and the unique interaction of CuO with H2S. At elevated temperature exposure to H2S resulted in the conversion of CuO to CuS, which being metallic in nature causes a drastic change in the resistance of the sensor films. Formation of nano p-n junctions is supported by the increase in the sensor resistance upon CuO modification and is further corroborated by the work function studies.
| Original language | English |
|---|---|
| Pages (from-to) | 525-532 |
| Number of pages | 8 |
| Journal | Sensors and Actuators, B: Chemical |
| Volume | 188 |
| DOIs | |
| Publication status | Published (in print/issue) - 26 Aug 2013 |
Funding
This work is partly supported by “ DAE-SRC Outstanding Research Investigator Award ” ( 2008/21/05-BRNS ) and “ Prospective Research Funds ” ( 2008/38/02-BRNS ) granted to D.K.A. Authors would like to thank Dr. D. Bhattacharya and Dr. S. Basu for their help with GIXRD measurements. One of the authors CP thanks Dr. F.Z. Haque, MANIT, Bhopal for her support. Niranjan Ramgir completed his PhD (Physics) in 2006 from National Chemical Laboratory, Pune, India. After completing his Humboldt fellowship at Nanotechnology Group, University of Freiburg, Germany, he joined Bhabha Atomic Research Centre as Scientific Officer. His current research work is focused on applications of organic and inorganic semiconducting materials like polypyrrole, polyaniline, ZnO, WO 3 , CuO and SnO 2 based thin films and nanostructures for sensing, e-nose and photovoltaic applications. Mr. C.P. Goyal is presently working as a project trainee, at Technical Physics Division, BARC. He is pursuing his masters in nanotechnology at Maulana Azad National Institute of Technology (MANIT), Bhopal. His research interest includes growth, charge transport and gas sensing in particular for e-nose applications of metal oxide thin films and nanostructures. Mr. Preetam Kumar Sharma is presently working as a project trainee, at Technical Physics Division, BARC. He is pursuing his masters in nanotechnology at University of Rajasthan, Jaipur. His research interest includes study of growth and applications of organic and inorganic nanostructures for gas sensing and e-nose applications. Mr. U.K. Goutam is presently working as Scientific Officer (D) at Technical Physics Division of BARC/RRCAT (Indore). He joined Bhabha Atomic Research Centre in 2008 through 49th batch of training school. His present interest includes beamline design and development, spintronics, nanomaterials and XPS investigations. Dr. S. Bhattacharya is presently working as a Scientific Officer at BARC. He has completed his PhD in Physics from Barkatullah university, Bhopal. His present interests include development of materials for thermoelectric device as well as fabrication of thermoelectric device, and analysis of microstructures using scanning electron microscope and Energy dispersive analysis of X-rays. Ms. Niyanta Datta has completed her B.Sc. (Hons) in Physics from Delhi University and M.Sc in Physics from IIT Roorkee in 2008. She joined Bhabha Atomic Research Centre in 2008 through 52nd batch of training school. Currently she is working as a Scientific Officer C and her interests include study of charge transport and gas sensing properties of various nanostructures. Dr. M. Kaur received her PhD from Devi Ahilya Vishwavidyalaya, Indore in 1998. Her thesis work involved effect of heavy ion irradiation on high temperature superconductors. She joined Bhabha Atomic Research Centre, Mumbai in 1999 as research associate. Her present interests include development of metal oxide thin films and nano-materials for sensing toxic gases. Dr. A.K. Debnath is presently working as Scientific Officer (F) at Technical Physics Division of BARC. He has extensively worked on oxide materials based gas sensor, particularly for H 2 S detection. His current research interest is to understand the charge transport and gas sensing properties of ultra thin films of organic semiconductors grown using MBE. Dr. D.K. Aswal joined Bhabha Atomic Research Centre in 1986 through 30th Batch of Training School after completing M.Sc. (Physics) from Garhwal University and is presently Head of Thin Films Devices Section. His area of scientific interest is condensed matter physics, specializing in device-oriented research leading to hybrid molecule-on-Si nanoelectronics, thermoelectric devices, and gas sensors. He is a recipient of several international fellowships including, JSPS fellowship, Japan (1997–1999), IFCPAR fellowship, France (2004–2005), BMBF fellowship, Germany (2006) and CEA fellowship, France (2008). He is recipient of several awards, including “MRSI Medal 2010”, “Homi Bhabha Science and Technology Award-2007”, “DAE-SRC Outstanding Research Investigator Award-2008”, and “Paraj: Excellence in Science Award, 2000”. Dr. S.K. Gupta joined Bhabha Atomic Research Centre in 1975 and is presently Head of Technical Physics Division. Over the years, he has worked on space quality silicon solar cells, high temperature superconductor thin films and single crystals, gas sensors and thermoelectric materials. He has carried out extensive studies on vortex dynamics in superconductors. He is a member of the National Academy of Sciences, India.
Keywords
- CuO
- Gas sensing
- HS
- Nano p-n junction
- WO
Fingerprint
Dive into the research topics of 'Selective H2S sensing characteristics of CuO modified WO 3 thin films'. Together they form a unique fingerprint.Cite this
- APA
- Author
- BIBTEX
- Harvard
- Standard
- RIS
- Vancouver