Hongfei Zheng

Ni12P5 nanoparticles embedded into porous g-C3N4 nanosheets as a noble-metal-free hetero-structure photocatalyst for efficient H2 production under visible light

Transition metal phosphides (TMPs) have recently been thrust into the limelight as promising substitutes for precious noble metal-based cocatalysts for photocatalytic H2 evolution. Herein, colloidally synthesized Ni12P5 nanoparticles were successfully embedded into porous g-C3N4 nanosheets through a facile solution-phase approach under sonication. The as-prepared photocatalysts with an optimum 5 wt% anchoring of Ni12P5 (5NP-CN) displayed an excellent H2 production activity of 535.7 μmol g−1 h−1 under visible light irradiation. The high apparent quantum yield (AQY) of 4.67% at 420 nm was achieved in the 5NP-CN system for the production of H2, exceeding a large scientific spectrum of literature studies on the TMP-based catalysts. The superior photocatalytic H2 evolution of Ni12P5/g-C3N4 was predominantly attributed to the formation of intimate contact interfaces, in which Ni12P5 nanoparticles with high purity and good crystallinity were homogeneously embedded into the porous g-C3N4 nanosheets, thus facilitating the separation and transfer of photogenerated charge carriers. Meanwhile, a possible photocatalytic mechanism of Ni12P5/g-C3N4 hybrid nanocomposites was proposed and corroborated by photoluminescence (PL) spectroscopy and photoelectrochemical (PEC) results. As such, the present reported synthetic route to the g-C3N4-based photocatalysts incorporating Ni12P5 paves a new way for the advancement of g-C3N4 and a cornucopia of colloidal nanocrystals, which will be auspicious toward the nanoarchitecture engineering of noble-metal-free heterojunction interfaces for application in renewable energy production.

Hierarchical ZnIn2S4/MoSe2 Nanoarchitectures for Efficient Noble-Metal-Free Photocatalytic Hydrogen Evolution under Visible Light

A highly efficient visible-light-driven photocatalyst is urgently necessary for photocatalytic hydrogen generation through water splitting. Herein, ZnIn2 S4 hierarchical architectures assembled as ultrathin nanosheets were synthesized by a facile one-pot polyol approach. Subsequently, the two-dimensional-network-like MoSe2 was successfully hybridized with ZnIn2 S4 by taking advantage of their analogous intrinsic layered morphologies. The noble-metal-free ZnIn2 S4 /MoSe2 heterostructures show enhanced photocatalytic H2 evolution compared to pure ZnIn2 S4 . It is noteworthy that the optimum nanocomposite of ZnIn2 S4 /2 % MoSe2 photocatalyst displays a high H2 generation rate of 2228 μmol g-1  h-1 and an apparent quantum yield (AQY) of 21.39 % at 420 nm. This study presents an unprecedented ZnIn2 S4 /MoSe2 metal-sulfide-metal-selenide hybrid system for H2 evolution. Importantly, the present efficient hybridization strategy reveals the potential of hierarchical nanoarchitectures for a multitude of energy storage and solar energy conversion applications.

Enhanced Microwave Absorption Properties by Tuning Cation Deficiency of Perovskite Oxides of Two-Dimensional LaFeO3/C Composite in X-Band

Development of microwave absorption materials with tunable thickness and bandwidth is particularly urgent for practical applications but remains a great challenge. Here, two-dimensional nanocomposites consisting of perovskite oxides (LaFeO3) and amorphous carbon were successfully obtained through a one pot with heating treatment using sodium chloride as a hard template. The tunable absorption properties were realized by introducing A-site cation deficiency in LaFeO3 perovskite. Among the A-site cation-deficient perovskites, La0.62FeO3/C (L0.62FOC) has the best microwave absorption properties in which the maximum absorption is -26.6 dB at 9.8 GHz with a thickness of 2.94 mm and the bandwidth range almost covers all X-band. The main reason affecting the microwave absorption performance was derived from the A-site cation deficiency which induced more dipoles polarization loss. This work proposes a promising method to tune the microwave absorption performance via introducing deficiency in a crystal lattice.

Electrical transport properties in Co nanocluster-assembled granular film

A Co nanocluster-assembled granular film with three-dimensional cross-connection paralleled conductive paths was fabricated by using the plasma-gas-condensation method in a vacuum environment. The temperature-dependent longitudinal resistivity and anomalous Hall effect of this new type granular film were systematically studied. The longitudinal resistivity of the Co nanocluster-assembled granular film first decreased and then increased with increasing measuring temperature, revealing a minimum value at certain temperature, T min. In a low temperature region ( T < T min), the barrier between adjacent nanoclusters governed the electrical transport process, and the temperature coefficient of resistance (TCR) showed an insulator-type behavior. The thermal fluctuation-induced tunneling conduction progressively increased with increasing temperature, which led to a decrease in the longitudinal resistivity. In a high temperature region, the TCR showed a metallic-type behavior, which was primarily attributed to th...

Size-dependent electrical transport properties in Co nanocluster-assembled granular films

A series of Co nanocluster-assembled films with cluster sizes ranging from 4.5 nm to 14.7 nm were prepared by the plasma-gas-condensation method. The size-dependent electrical transport properties were systematically investigated. Both of the longitudinal resistivity (

3D Graphene Encapsulated Hollow CoSnO3 Nanoboxes as a High Initial Coulombic Efficiency and Lithium Storage Capacity Anode

{\rho }_{xx}

Toward noble-metal-free visible-light-driven photocatalytic hydrogen evolution: Monodisperse sub–15 nm Ni2P nanoparticles anchored on porous g-C3N4 nanosheets to engineer 0D-2D heterojunction interfaces

ρxx) and saturated anomalous Hall resistivity (