We present a density functional theory study of 3d transition-metal (TM) atoms (Sc–Zn) adsorbed on a phosphorene sheet. We show that due to the existence of lone pair electrons on P atoms in phosphorene, all the TM atoms, except the closed-shell Zn atom, can bond strongly to the phosphorene with sizable binding energies. Moreover, the TM@phosphorene systems for TM from Sc to Co exhibit interesting magnetic properties, which arise from the exchange splitting of the TM 3d orbitals. We also find that strain is an effective way to control the magnetism of TM@phosphorene systems by tuning the interaction of the TM with phosphorene and, thus, the relative positions of in-gap TM 3d orbitals. In particular, a small biaxial strain could induce a magnetic transition from a low-spin to a high-spin state in phosphorene decorated by Sc, V, or Mn. These results clearly establish the potential for phosphorene utilization in innovative spintronic devices.

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The interfacial sites of supported metal catalysts are often critical in determining their performance. Single-atom catalysts (SACs), with every atom contacted to the support, can maximize the number of interfacial sites. However, it is still an open question whether the single-atom sites possess similar catalytic properties to those of the interfacial sites of nanocatalysts. Herein, we report an active-site dependent catalytic performance on supported gold single atoms and nanoparticles (NPs), where CO oxidation on the single-atom sites is dramatically promoted by the presence of H 2 O whereas on NPs’ interfacial sites the promoting effect is much weaker. The remarkable H 2 O promoting effect makes the Au SAC two orders of magnitude more active than the commercial three-way catalyst. Theoretical studies reveal that the dramatic promoting effect of water on SACs originates from their unique local atomic structure and electronic properties that facilitate an efficient reaction channel of CO + OH.

Bioactive surfaces with appropriate hydrophilicity for protein immobilization can be achieved by hydrophobin II (HFBI) self-assembly on mica and polydimethylsiloxane (PDMS) surfaces. X-ray photoelectron spectroscopy and water contact angle measurements illustrated that the surface wettability can be changed from superhydrophobic (PDMS) or superhydrophilic (mica) to moderately hydrophilic, which is suitable for protein (chicken IgG) immobilization on both substrate surfaces. The results suggest that HFBI assembly, one kind of hydrophobin from Trichoderma reesei, may be a versatile and convenient method for the immobilization of biomolecules on diverse substrates, which may have potential applications in biosensors, immunoassays, and microfluidic networks.