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Hierarchical nanostructures with unique synergistic electronic effects and abundant active sites play an essential role in the field of electrocatalysis. In this work, 1D@2D hierarchical NiCo2O4@MIL-53(Fe) nanostructures are constructed via introducing MIL-53(Fe) over NiCo2O4nanoneedles grown on nickel foam [NiCo2O4@MIL-53(Fe)]. NiCo2O4@MIL-53(Fe) exhibits high catalytic activity of the oxygen evolution reaction due to the strong electronic interaction between NiCo2O4and MIL-53(Fe), as well as the hierarchical nanostructures that provide numerous active sites. In 1.0 M KOH, the NiCo2O4@MIL-53(Fe) can achieve the current densities of 10 and 100 mA cm–2with overpotentials of only 231 and 260 mV, respectively; the hierarchical catalysts show good electrochemical and structural stability, operating for more than 100 h at a current density of 10 mA cm–2without obvious decay.

Developing efficient electrocatalysts for industrial alkaline hydrogen evolution reaction (HER) is important for alleviating energy problems and achieving decarbonization. Here, a multimetal alloyed NiMoCo coating was in situelectrodeposited on Ni mesh as an HER electrocatalyst. The obtained cathode exhibits ultrahigh HER activity in alkaline environments, requiring only low overpotentials of 13.7 and 146.0 mV in 1 M KOH to achieve current densities of 10 and 200 mA cm–2, along with a robust stability of over 120 h at an operating current density of 400 mA cm–2. The introduction of Co elements into NiMo-based alloys could significantly change the surface morphology from a planar to a three-dimensional structure for exposing abundant active sites; moreover, strong electronic interaction between multimetal alloyed sites is beneficial to modulate alkaline HER activity. The full alkaline water splitting electrolyzer, which consisted of electrodeposited multimetal alloyed NiMoCo as the cathode and NiMoFe as the anode, was constructed, showing a cell voltage as low as 1.437 V to obtain the current density of 10 mA cm–2and 1.703 V for 200 mA cm–2. This work would pave a new avenue to design and fabricate multimetal alloyed electrocatalysts directly grown on an industrial porous conductive substrate.

Metal-organic frameworks (MOFs) possess the features of highly porosity-tunable and electronic-tunable structures. Taking advantages of these merits, we successfully installed high-valence W6+ions onto the Ti-oxo clusters of MIL-125(Ti) (W-MIL-125). The installed W6+ions which form a W-O-Ti structure trigger the metal-to-cluster charge transfer (MCCT), together with an enhanced light absorption. Structural and spectroscopic characterizations reveal that the MCCT process optimizes the charge transfer process and efficiently separates the photogenerated electron-hole spatially. The as-obtained sample of 3.45 W-MIL-125 with optimized electronic structure demonstrates an enhanced photocatalytic hydrogen evolution performance of 1110.7 ± 63.7 µmol g−1h−1under light irradiation, which is 4.0 times that of the pristine MIL-125(Ti). This work will open up a new avenue for local structural modification of MOFs to boost photocatalytic performance.

Sub-3 nm ultrasmall Bi2Se3nanodots stabilized with bovine serum albumin were successfully synthesized through a reaction of hydroxyethylthioselenide with bismuth chloride in aqueous solution under ambient conditions. These nanodots exhibit a high photothermal conversion efficiency (η = 50.7%) due to their strong broad absorbance in the near-infrared (NIR) window and serve as a nanotheranostic agent for photoacoustic imaging and photothermal cancer therapy. In addition, they also display radioenhancement with a ratio of 6% due to their sensitivity to X-rays, which makes them a potential sensitizer for radiotherapy. These nanodots were also labled with radioactive 99mTc for quantification of their biodistribution by single-photon-emission computed tomography (SPECT)/computed tomography (CT) imaging. Our work demonstrates the potential of ultrasmall Bi2Se3nanodots in multimodal imaging-guided synergetic radiophotothermal therapy of cancer.