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Flower-like porous carbon has fascinated significant attention due to its outstanding and exceptional properties. However, controlled synthesis of porous carbon with adjustable morphology, highly active sites and cross-linked pore channels remains still a great challenge. Herein, an inimitable dissolution–reassembly anisotropic growth strategy was firstly demonstrated for the fabrication of idiographic orchid-like hierarchical porous carbon with ultra-thin multilayer carbon sheets, high specific surface area (1063 m2 g−1), large pore volume (0.82 cm3 g−1) and rich nitrogen content (7.6 wt%). Highly reactive phloroglucinol and EDA aggregated magically and SiO2 acted as a pore former. Ingeniously, acetone acted as a "surgical knife," which cut the composite of SiO2@phloroglucinol–EDA into many tiny units and further anisotropic growth into orchid-like polymers. The width and thickness of the carbon petals can be effectively controlled with the diversification of acetone concentration. Intriguingly, monodisperse hollow carbon nanospheres could be harvested with silicon-deficient system, which may offer new insight into the construction of functionalized carbon materials with hollow architecture. Owing to the unmatched superstructures, orchid-like carbon materials can be employed as an ideal drug carrier and dye adsorbent. Figure Schematic illustration of solid carbon nanosphere, hollow carbon nanosphere and OHPC-25. For the first time, a novel dissolution–reassembly route based on strong hydrogen-bonding interaction was developed to prepare unique orchid-like hierarchical porous carbon, in which phloroglucinol acted as a carbon precursor and EDA both as a base catalyst and as a nitrogen precursor. The critical step to this synthetic approach was the ingeniously employed acetone as a "surgical knife" to cut the composite of SiO2@phloroglucinol–EDA into many tiny units, and these units were reassembled into orchid-like polymers. After adding acetone, the morphology of carbon materials has changed from solid nanospheres to hollow nanospheres. This strategy did not use any template as the cavity, which may offer a new insight into the comprehension of synthesized functionalized carbon materials with hollow architecture. [ABSTRACT FROM AUTHOR]

Developing efficient and durable oxygen evolution reaction (OER) electrocatalysts with non-noble elements is particularly urgent for electrochemical water splitting. Herein, we report heterostructural Ni3S2–Fe5Ni4S8 hybrids directly grown on redox-NiFe foams (denoted as NFS/rNF) as excellent pre-catalysts for OER in 1 M KOH media. The electrochemical performance can be tuned by amount of sulfur source, and the optimized electrode only needs low overpotentials of 199 mV and 240 mV to attain 10 mA cm−2 and 100 mA cm−2, respectively. Moreover, the overpotential is further reduced to 231 mV to deliver 100 mA cm−2 after multi-cyclic voltammogram scans, due to the exposure of abundant in situ generated Ni(Fe)OOH species. Excellent stability with continuous 40 h operation is also demonstrated. Our study provides a new strategy for direct synthesis of self-standing integrated hybrid electrodes for efficient and durable water oxidation. [ABSTRACT FROM AUTHOR]

Herein, a series of phosphorus-doped CoMoO4 rod bundles electrocatalysts on 3D nickel foams have been successfully synthesized and exploited as efficient hydrogen evolution reaction (HER) electrocatalyst in 1 M KOH. The incorporation of phosphorus into CoMoO4 can significantly promote the HER activity, and the CoMoO4 bundles phosphorized at 350 °C exhibited the optimum activity, which only required low overpotentials of 56 and 148 mV to deliver cathodic current densities of 10 mA cm−2 and 100 mA cm−2, respectively. This electrode also presented considerable long-term electrochemical stability with negligible delay after 30 h operation and 3000 accelerated cyclic voltammetry cycles. Our study provides a superior earth-abundant catalyst for efficient HER in alkaline media, which also suggests that P doping engineering is an effective way to boost the HER activity of transition metal-based oxides. [ABSTRACT FROM AUTHOR]