Direct Observation of Transient Surface Species during Ge Nanowire Growth and Their Influence on Growth Stability

摘要: Surface adsorbates are well-established choreographers of material synthesis, but the presence and impact these short-lived species on semiconductor nanowire growth largely unknown. Here, we use infrared spectroscopy to directly observe surface adsorbates, hydrogen atoms methyl groups, chemisorbed sidewall show they essential for stable Ge nanowires via vapor-liquid-solid mechanism. We quantitatively determine coverage during by comparing ν(Ge-H) absorption bands from operando measurements (i.e., growth) those after saturating with atoms. This method provides sub-monolayer chemical information at relevant reaction conditions while accounting heterogeneity sites their evolution elongation. Our findings demonstrate that changes bonding critical understand synthesis provide new guidelines rationally selecting catalysts, forming heterostructures, controlling dopant profiles.