Metal nanocrystals (NCs) have been recognized as an important class of nanomaterials by virtue of their unique surface plasmon resonance (SPR) effect and pivotal roles as electron traps in photocatalysis. Nevertheless, it is still challenging to unambiguously unravel and simultaneously harness the dual synergistic roles of metal NCs in a single photocatalytic system for solar-to-chemical energy conversion. Herein, an efficient ligand-triggered electrostatic self-assembly strategy was developed to achieve the spontaneous and monodispersed attachment of Au NCs onto 1D WO nanorods (NRs) via pronounced electrostatic attractive interaction, in which tailor-made positively charged Au NCs were closely integrated with negatively charged WO NRs. The intimate integration of Au NCs with WO NRs at the nanoscale could significantly benefit the extraction, separation, and migration of plasmon-induced energetic hot carriers over Au NCs and promote the separation of photogenerated charge carriers over the WO substrate. Such a cooperative synergy stemming from SPR and the electron-withdrawal effects of the Au NCs resulted in distinctly enhanced photoredox catalytic performances for plasmonic photocatalysis under both simulated solar and visible light irradiation. Our study highlights the significance of utilizing a rational interface design between metal NCs and semiconductors for excavating the multifarious roles of metal NCs in substantial solar energy conversion.

Hierarchical metals oxide nanostructure derived from annealing of metal−organic frameworks (MOFs) usually have large particle size and low specific surface area and, as a result their activities, become limited. In this work, we incorporated KMnO 4 into Prussian blue (PB) microcubes and obtained Mn-doped α-Fe 2 O 3 nanoboxes by annealing the complex. We found that KMnO 4 stayed inside the pores of the PB framework and restricted the crystal growth of α-Fe 2 O 3 during annealing. Consequently, the Mn-doped Fe 2 O 3 nanoboxes have small particle size, large specific area (452 m 2 /g), and a significant amount of adsorbed oxygen in the form of OH − on the surface as determined by X-ray photoelectron spectroscopy. It could serve as an adsorbent to quickly remove the trace-level (40 mg/L) Pb 2+ from water. Within 1 min, this nanoadsorbent (0.2 g/L) extracted >70% Pb 2+ in the solution, and >91.6% in 15 min. Besides, it also selectively captures Pb 2+ (40 mg/L) from a synthetic Pb/Zn mining wastewater containing Zn 2+ (40 mg/L) and various kinds of interfering ions (Na + , K + , Mg 2+ , Ca 2+ , SO 4 2− , NO 3 − , Cl − ). The maximizing capacity of Pb 2+ reaches to 900 mg/g when treating concentrated Pb 2+ solution (1g/L). The spent adsorbent could be easily retrieved from the solution by magnetic separation. We anticipate the findings here will help to inspire the design of other novel MOFs-derived nanomaterials.

Integrating individual functional materials into elegant nanoarchitectures holds great promise for creating high-efficiency photosynthesis systems with unique structuredirecting merits. Herein, an all-solid-state metal-based Zscheme photocatalytic system consisting of well-defined onedimensional WO 3 @Au@CdS core−shell heterostructure has been progressively and rationally designed by a green and facile two-step wet-chemistry approach. Significantly, it was uncovered that Au ingredient sandwiched in between the interfacial domain of WO 3 and CdS layer plays simultaneous dual roles in boosting the visible-light-driven photoactivities of core−shell ternary heterostructure, that is, as interfacial charge-transfer mediator to expedite vectorial Z-scheme electron transfer between CdS and WO 3 and plasmonic photosensitizer to trigger the generation of plasmon-induced hot electrons, thereby substantially augmenting the photoelectron density in a photoredox catalytic system. Such cooperative concurrent dual roles of Au nanocrystal in Z-scheme photocatalytic system results in the versatile and considerably enhanced photoredox performances of plasmonic WO 3 @Au@CdS core−shell heterostructure toward anaerobic reduction of aromatic nitro compounds to corresponding amines and mineralization of organic pollutants under visible light irradiation at ambient conditions. Moreover, predominant active species during the photoredox catalysis were accurately determined, on the basis of which the photocatalytic mechanism was reasonably deduced and clearly elucidated. This work would provide a quintessential paradigm to uncover the essential roles of metal nanocrystals along with their cooperative synergy in Z-scheme photocatalytic system for substantial solar energy conversion.