Anisotropic nanoparticles stabilized by cetyltrimethylammonium bromide (CTAB) are notoriously difficult to homogenously functionalize using conventional gold-thiol chemistry. Using surface assisted laser desorption time of flight mass spectroscopy and scanning transmission electron microscopy-energy dispersive X-ray spectroscopy, we demonstrate that silver species adsorbed on the particle surface prevent 10 effective surface functionalization. When covered by a thin gold film, particle functionalization was drastically improved. A thiol-containing polypeptide was immobilized on arrowhead gold nanorods (NRs) and was subsequently able to selectively heteroassociate with a complementary polypeptide resulting in a folding-mediated bridging aggregation of the NRs. Despite using arrowhead NRs with a pronounced difference in surface arrangement on the {111} facets on the arrowheads compared to the 15 {100} facets at the particle sides, the polypeptides were efficiently and homogeneously immobilized on the particles after gold film overgrowth.

A facile strategy to prepare MoS 2 -MoO 3 hybrid nanomaterials is developed, based on the heat-assisted partial oxidation of lithium-exfoliated MoS 2 nanosheets in air followed by thermal-annealing-driven crystallization. The obtained MoS 2 -MoO 3 hybrid nanomaterial exhibits p-type conductivity. As a proof-of-concept application, an n-type SiC/p-type MoS 2 -MoO 3 heterojunction is used as the active layer for light-emitting diodes. The origins of the electroluminescence from the device are theoretically investigated. This facile synthesis and application of hybrid nanomaterials opens up avenues to develop new advanced materials for various functional applications, such as in electrics, optoelectronics, clean energy, and information storage.

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The demand for a dual catalyst that maintains high catalytic performance at low temperatures for simultaneous propane and carbon monoxide (CO) oxidation with repeated usage is significant, yet lacking in the literature. Here, we report a mesoporous platinum–ruthenium (0.5 wt % Pt and 0.5 wt % Ru)-doped ceria–zirconia bifunctional catalyst achieving T 95 at ∼260 °C and T 100 below 300 °C for propane oxidation, along with simultaneous 100% CO conversion at ∼200 °C. The performance is maintained after accelerated aging at 1000 °C for 24 h. The consistent superior performance over prolonged cycling is multifaceted, contributed by an optimal balance among nanostructure, metal oxide support/metal dopant system, and composition. The ceria–zirconia support gives enhanced oxygen storage and release capabilities coupled with thermal endurance. The porous catalyst has numerous catalytic sites with short reaction paths doped with Pt–Ru nanoparticles, leading to increased efficiency in bond cleavage for propane and endowing CO tolerance. Nanosized particles with narrow size distribution and uniform metal dispersion are effective in promoting catalytic activity toward oxidation reactions at low temperatures. This catalyst is thermally stable, durable, and active toward propane oxidation, and its catalytic performance is not compromised by the simultaneous presence of CO.

The synthesis of dual phase Li4Ti5O12/TiO2(B) composite remains a tremendous challenge due to the easy formation of anatase TiO2 instead of Li4Ti5O12 in the process. In this work, Li4Ti5O12/TiO2(B) heteronanostructures comprising porous TiO2(B) nanofibers integrated with Li4Ti5O12 nanocrystals are synthesized and applied as anode for lithium-ion batteries. Benefiting from the complementary advantages of higher theoretical capacity of TiO2(B) with favourable pseudocapacitive behaviour and excellent cyclability of Li4Ti5O12, this heteronanostructure demonstrates a superior lithium-ion storage performance in terms of high discharge capacity and remarkable long-term stability. As a result, Li4Ti5O12/TiO2(B) heteronanostructures manifest discharge capacity of 130 mAhg−1 and capacity retention of 93 % at high rate of 1.75 Ag-1, compared to those of TiO2(B) pristine of 90 mAhg−1 and 75 %. The superior electrochemical performance demonstrated by Li4Ti5O12/TiO2(B) heteronanostructure reveals a new direction of integration of Li4Ti5O12 into TiO2(B) to improve both the capacity performance and cyclability. Acknowledgements This project is financially supported by Innovation and Technology Fund (ITS/378/13) and Internship Programme (InP/299/14) from Innovation and Technology Commission, Hong Kong, HKU Strategic Research Theme on Clean Energy, University Development Fund for Initiative for Clean Energy and Environment, and our industry partner – Gold Peak (GP) Batteries Limited. Figure 1