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Phosphorene, a new elemental two-dimensional material, has attracted increasing attention owing to its intriguing electronic properties. In particular, pristine phospohorene, due to its ultrahigh surface-volume ratio and high chemical activity, has been shown to be promising for gas sensing (Abbas et al 2015 ACS Nano 9 5618). To further enhance its sensing ability, we perform first-principles calculations based on density functional theory to study substitutionally doped phosphorene with 17 different atoms, focusing on structures, energetics, electronic properties and gas sensing. Our calculations reveal that anionic X (X = O, C and S) dopants have a large binding energy and highly dispersive electronic states, signifying the formation of covalent X-P bonds and thus strong structural stability. Alkali atom (Li and Na) doping is found to donate most of the electrons in the outer s-orbital by forming ionic bonds with P, and the band gap decreases by pushing down the conduction band, suggesting that the optical and electronic properties of the doped phosphorene can be tailored. For doping with VIIIB-group (Fe, Co and Ni) elements, a strong affinity is predicted and the binding energy and charge transfer are correlated strongly with their electronegativity. By examining NO molecule adsorption, we find that these metal doped phosphorenes (MDPs) in general exhibit a significantly enhanced chemical activity compared with pristine phosphorene. Our study suggests that substitutionally doped phosphorene shows many intriguing electronic and optic properties different from pristine phosphorene and MDPs are promising in chemical applications involving molecular adsorption and desorption processes, such as materials growth, catalysis, gas sensing and storage.

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Polyhydroxamate desferrioxamines (DFO) are nontoxic siderophores endowed with high potential for development of therapeutic chelating agents. Herein, we report a modular and convergent strategy for diverse synthesis of macrocyclic and linear DFOs. The strategy employed orthogonally protected N‐hydroxy‐N‐succinylcadaverine building blocks, which allowed bidirectional extension of the DFO structure. The efficiency of the new strategy was demonstrated by the total synthesis of 44‐membered macrocyclic DFO‐T1, as well as four related DFO compounds in 11–13 linear steps and 2.1 %–10 % overall yields. Comparison of the iron binding affinity of the DFOs revealed DFO‐E as the best chelator.

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