Search

This Communication demonstrates a novel and in situ simultaneous cavitation-doping (SCD) approach to construct bimetallic metal-doped cobalt metal-organic framework hollow nanospheres (CoM-MOF HNSs, with M = Ru or Fe). The key point of the SCD approach is the careful balance between the kinetics of Co-MOF being etched and the coordinative growth of a more stable CoM-MOF shell induced by Lewis acid (MCl

Exploring highly active and inexpensive electrocatalysts for oxygen evolution reaction (OER) is considered to be one of the preconditions for the development of energy and environment-related technologies. Nickel-based layered double hydroxides (LDHs) are extensively-studied OER electrocatalysts, but they still require relatively high overpotentials to achieve threshold current densities. In this work, iron-doped nickel-vanadium hydroxide microspheres (Fe-doped NiV HMS) were synthesized by doping iron ions into the NiV HMS through a facile cation-exchange method. The Fe-doped NiV HMS are hollow hierarchical structure stacked by high-density perpendicularly-lying nanosheets, which provide enough space for electrolyte penetration and diffusion. Owing to optimized composition and hollow hierarchical structure, the Fe-doped NiV HMS exhibits excellent electrocatalytic performance, which possessed a very low running overpotential (255 mV at 10 mA cm

Metallic sulfides have emerged as highly active, durable, and robust electrocatalysts for the electrocatalytic hydrogen evolution reaction (HER) due to their intriguing electronic and catalytic properties. One of the important strategies to further enhance their HER performance is to build multimetallic nanostructures by tuning the electronic state. Here we combine multimetallic structures and metal sulfides, and report an efficient strategy for the in situ surface-derivation of molybdenum sulfide nanosheets (MoS2 NSs) on Ag–Pd–Mo alloy nanowires (AgPdMo NWs) to form AgPdMo/MoS2 NWs. The heterostructure incorporates AgPdMo NWs with high conductivity and MoS2 NSs with abundant active sites, which act synergistically in alkaline solution. The as-tuned AgPdMo/MoS2 NWs exhibit Pt-like electrocatalytic performance for the HER, with a small overpotential of 54 mV at a current density of 10 mA cm−2 and a low Tafel slope of 72 mV dec−1. The present work demonstrates a potential strategy for designing heterostructures with multimetallic composition by in situ surface-derivation with enhanced performance in water splitting.

One-dimensional multimetallic nanotubes with mesoporous walls are promising electrocatalysts for fuel cells on account of their distinct morphology and tunable composition. In the present work, we ...

The rational-design and synthesis of transition-metal compounds with outstanding electrochemical activity and durability for renewable energy systems have attracted tremendous research interest in recent years. Herein, we report a facile and unique strategy to synthesize N-doped carbon nanotube-encapsulated Ni nanoparticles on reduced graphene oxide (Ni@NC-rGO). The optimized nanostructure determines the synergetic effects among the Ni nanoparticles, N-doped CNTs and graphene nanosheets, thus resulting in extraordinary electrochemical performances. When applied as an anode for lithium-ion batteries (LIBs), the Ni@NC-rGO electrode displayed high reversible capacity, stable cycling performance and superior rate capability. Moreover, the resulting Ni@NC-rGO nanocomposites exhibited low overpotential and considerable durability for the hydrogen evolution reaction (HER). Our study may provide a feasible methodology for the preparation of high-performance nanostructured materials for practical energy storage and conversion applications.

The development of high-efficiency nonprecious electrocatalysts based on inexpensive and Earth abundant elements is of great significance for renewable energy technologies. Group VIII transition metal phosphides (TMPs) gradually stand out due to their intriguing properties including low resistance and superior catalytic activity and stability. Herein, we adopt a unique MOF-derived strategy to synthesize transition metal phosphide nanoboxes which can be employed as electrocatalysts for the hydrogen evolution reaction. During this process, we converted a Co-MOF to a CoNi-MOF by ion exchange and low-temperature phosphating to achieve CoNiP nanoboxes. The CoNiP nanoboxes can reach a current density of 10 mA cm-2 at a low overpotential of 138 mV with a small Tafel slope of 65 mV dec-1.

Metallic sulfides have emerged as highly active, durable, and robust electrocatalysts for the electrocatalytic hydrogen evolution reaction (HER) due to their intriguing electronic and catalytic properties. One of the important strategies to further enhance their HER performance is to build multimetallic nanostructures by tuning the electronic state. Here we combine multimetallic structures and metal sulfides, and report an efficient strategy for the in situ surface-derivation of molybdenum sulfide nanosheets (MoS

An ultrathin, ordered, and packed protein film, consisting of the 2-mercaptoacetic acid (MAA), polydimethyldiallylammonium chloride (PDDA), and wild-type (WT) photosynthetic reaction center (RC; termed as WT-RC) or its pheophytin (Phe)-replaced counterpart (termed as Phe-RC), was fabricated by self-assembling technique onto gold electrode for facilitating the electron transfer (ET) between RC and the electrode surface. Near-infrared (NIR)-visible (Vis) absorption and fluorescence (FL) emission spectra revealed the influence of pigment substitution on the cofactors arrangement and excitation relaxation of the proteins, respectively. Square wave voltammetry (SWV) and photoelectric tests were employed to systematically address the differences between the WT-RC films and mutant ones on the direct and photo-induced ET. The electrochemical results demonstrated that ET initiated by the oxidation of the primary donor (P) was obviously slowed down, and the formed P+ had more population as well as more positive redox potential in the Phe-RC films compared with those in the WT ones. The photoelectrochemical results displayed the dramatically enhanced photoelectric performances of the mutant ones, further suggesting the slow-down formation of final charge-separated state in Phe-RC. The functionalized protein films introduced in this paper provided an efficient approach to sensitively probe the redox cofactors and ET differences resulting from only minor changes in pigment arrangement in the pigment–protein complex. The favored ET process observed for the membrane proteins RC was potentially valuable for a deep understanding of the multi-step biological ET process and development of versatile bioelectronic devices.

Photosynthetic reaction center (RC), a robust transmembrane pigment-protein complex, works as the crucial component participating the primary event of the photo-electrochemical conversion in bacteria. Sparked by the high photo-induced charge separation yield (ca. 100%) of RC, great interests have been aroused to fabricate versatile RC-functionalized nano-composite films for exploring the initial photosynthetic electron transfer (ET) of RC, and thus exploiting well-designed bio-photoelectric converters. In this review, we classify and summarize the current status about the concepts and methods of constructing RC-immobilized nano-composite films or devices for probing the photo-induced ET, and applying to novel bioelectronics if it is possible.

Novel three-dimensional wormlike mesoporous WO(3)-TiO(2) films with tailored pore size (approximately 7.1 nm) were applied to prepare the bio-photoelectrodes (Bio-PEs) through direct entrapping the bacteria photosynthetic reaction center (RC) proteins. These mesoporous WO(3)-TiO(2) films exhibited unique characteristics in the specific loading of RC with high activity retained. Moreover, well-matched energy levels of WO(3)-TiO(2) and RC contributed to the photoelectric performance, especially in the red to near-infrared (NIR) region, of the derived Bio-PEs. Such strategy of manipulating the Bio-PEs based on well-designed mesoporous metal oxides and RC provides an alternative system to probe the photoinduced multiple-pathway electron transfer of photosensitive chromophores, which may open a new perspective to develop versatile bio-photoelectric devices.

In this paper, a MoO3 thin film was firstly electrodeposited on flexible ITO/PET substrates. Its electrochromic properties were examined using an electrochemical workstation coupled in situ with a charge-coupled device (CCD) spectrophotometer. The film was characterized by XRD and AFM. The electrodeposited MoO3 thin film on the ITO/PET substrate showed a large transmittance contrast between the colored and bleached states, a quick response, and good durability and reversibility. The low working potential range, –0.5 to 1.6 V (vs. Ag/AgCl), for the MoO3/ITO/PET film prepared in this work makes it a good candidate for flexible smart windows, as well as other plastic electrochromic devices.

A new kind of bio-nanocomposite photoelectrode was fabricated through direct immobilization of the bacterial photosynthetic reaction center (RC) proteins on a nanocrystalline TiO2 matrix prepared by anodic electrodeposition. The near-infrared (NIR)-visible absorption and fluorescence emission spectra displayed that structure and activity of the RC remained unaltered on the nano-TiO2 film surface. High efficient light-harvesting of the NIR light energy by RC contributed to the distinct enhancement of the photoelectric conversion on such nanoporous matrix, which would provide a new strategy to develop versatile biomimic energy convertors or photoelectric sensors.

Ordered three-dimensional (3-D) cage-like mesoporous mixed tungsten–titanium oxides (WO3–TiO2) with relatively high surface area (152 m2g−1) have been synthesized by employing Pluronic F108 tribloc...

A novel photoelectrode (PE) consisting of the pigment-exchanged photosynthetic reaction center (RC) trapped on the mesoporous WO3-TiO2 film was fabricated to facilitate bio-photoelectric conversion by manipulating the excitation relaxation of the proteins.