Guwahati: The researchers at the Indian Institute of Technology Guwahati (IITG) have developed a new form of semiconductor that can be used to identify trace chemicals using Surface Enhanced Raman Spectroscopy (SERS). The study can help in the development of SERS techniques that are cheaper than existing devices.
The IITG research study was published in a journal 2D Materials and Applications and was led by IIT Guwahati, department of physics and centre for nanotechnology, professor PK Giri. The published paper was co-authored by Tadasha Jena, Tarik Hossain, Upasana Nath, Manabendra Sarma, Hiroshi Sugimoto, Minoru Fujii, and PK Giri.
According to a press statement, the IIT Guwahati research team designed an ultrathin 2D dendritic nanostructure of the semiconductor, palladium di-selenide (PdSe2) and found that it exhibits high SERS amplification properties. The researchers used a method called chemical vapour deposition (CVD) to produce such structures.
The team used the semiconductor-based SERS technique to detect minuscule amounts of a dye name rhodamine-B deposited and tested the device over many months. No deterioration was found showing that these substrates are more stable than metal-based ones.
Explaining the rationale for their research, lead researcher PK Giri said: “The problem with using noble metal nanostructures is that they are costly, have poor environmental stability and poor reproducibility of detection. Semiconductors – materials that have electrical conduction properties intermediate to metals (conductors) and insulators – are being studied as alternatives to metal nanostructures. This is because they offer better chemical stability, a wider range of options, and lower cost than noble metal SERS substrates. However, the signal amplification in semiconductors is much lower than that of metal nanostructures.”
