An Accidental Discovery Of Nanotechnology Can Lead To Better Photo detectors

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The world of electronics is getting compact day by day. The shrinkage also means smaller wires that are capable of carrying current in an efficient manner. So, introducing the nanowires, special kind of wires that are approximately one thousand times slimmer than a regular human hair strand. These wires are capable enough to allow the flow of current through them in useful volume at an ascending scale that is being achieved by people currently. 


A research team recently discovered nanowires by accident; one of their other creations led to the discovery of nanowires that moved across the graphene surface. The so-called ‘nanocrawlers’ were very surprising because the makers expected the wires to come out of graphene surface like plant shoots. According to Tzahi Cohen-Karni, a materials science and engineering professor at the Carnegie Mellon University, “We looked at the results, and they were kind of mind-blowing. We set forth to understand why the nanowires crawled on the surface.”

The team was actually planning to grow germanium nanowires (GeNWs) over some single-layered graphene surfaces with the help of AuNPs (gold nanoparticles). The complete process was catalyzed by vapour-liquid-solid (VLS) growth mechanism. The process starts with a graphene monolayer that is formed from a process called low pressure chemical vapour deposition (LPCVD). Post this, a 2nm gold film evaporates over the graphene surface resulting into an annealing process that breaks down the film in AuNPs. 

It is an exciting discovery as its expected applications are diverse and will be useful in multiple fields. The biggest application of these will be in form of nanocrawlers that can be used in photodetectors. The nanocrawlers are capable of being photosensitive , which means these can be used in the conversion of electricity. Cahen-Karni further adds, “Photodetectors made with nanocrawlers could potentially detect smaller amounts of light than their vertical nanowire counterparts,”