The activity and accessibility of MoS 2 edge sites are critical to deliver high hydrogen evolution reaction (HER) efficiency. Here, a porous carbon network confining ultrasmall N-doped MoS 2 nanocrystals (N-MoS 2 /CN) is fabricated by a selftemplating strategy, which realizes synergistically structural and electronic modulations of MoS 2 edges. Experiments and density functional theory calculations demonstrate that the N dopants could activate MoS 2 edges for HER, while the porous carbon network could deliver high accessibility of the active sites from N-MoS 2 nanocrystals. Consequently, N-MoS 2 /CN possesses superior HER activity with an overpotential of 114 mV at 10 mA cm −2 and excellent stability over 10 h, delivering one of best MoS 2based HER electrocatalysts. Moreover, this study opens a new venue for optimizing materials with enhanced accessible catalytic sites for energy-related applications.

Considering the environment protection, “green” materials are increasingly explored for photovoltaics. Here, we developed a kind of quantum dots solar cell based on nitrogen-doped carbon dots. The nitrogen-doped carbon dots were prepared by direct pyrolysis of citric acid and ammonia. The nitrogen-doped carbon dots’ excitonic absorption depends on the N-doping content in the carbon dots. The N-doping can be readily modified by the mass ratio of reactants. The constructed “green” nitrogen-doped carbon dots solar cell achieves the best power conversion efficiency of 0.79 % under AM 1.5 G one full sun illumination, which is the highest efficiency for carbon dot-based solar cells.Electronic supplementary materialThe online version of this article (doi:10.1186/s11671-016-1231-1) contains supplementary material, which is available to authorized users.

A strongly coupled Bi2S3@CNT hybrid is fabricated and exhibits a stable Li‐storage capacity, retaining 405 mAh g−1 over 100 cycles at a rate of 1 A g−1. More importantly, the hybrid demonstrates robust rate capability, delivering 429 and 376 mAh g–1 at high rates of 2 and 5 A g–1, thereby suggesting its great potential for advanced rechargeable battery applications.

No abstract

A hybrid of N-doped carbon encapsulated ultrasmall Mo2C nanodots on Ti3C2Tx MXene exhibits excellent HER performance in the entire pH range.

We present a new general facile strategy for the preparation of protein-functionalized QDs in a single step at ambient conditions. We demonstrated that highly luminescent red to near-infrared (NIR) protein-functionalized QDs could be synthesized at room temperature in one second through a one-pot reaction that proceeds in aqueous solution. Herein protein-functionalized QDs were successfully constructed for a variety of proteins with a wide range of molecular weights and isoelectric points. The as-prepared protein-conjugated QDs exhibited high quantum yield, high photostabiliy and colloidal stability, and high functionalization efficiency. Importantly, the proteins attached to the QDs maintain their biological activities and are capable of catalyzing reactions and biotargeting. In particular, the as-prepared transferrin-QDs could be used to label cancer cells with high specificity. Moreover, we demonstrated that this synthetic strategy could be extended to prepare QDs functionalized with folic acids and peptides, which were also successfully applied to cancer cell imaging.

A hierarchical, branched Bi2S3–CNT hybrid was fabricated through a facile sonochemical approach which exhibited outstanding Li-storage capability.

High-performance and affordable electrocatalysts from earth-abundant elements are desirably pursued for water splitting involving hydrogen evolution reaction (HER) and oxygen evolution reaction (OER). Here, a bifunctional electrocatalyst of highly crystalline Mo C nanoparticles supported on carbon sheets (Mo C/CS) was designed toward overall water splitting. Owing to the highly active catalytic nature of Mo C nanoparticles, the high surface area of carbon sheets and efficient charge transfer in the strongly coupled composite, the designed catalysts show excellent bifunctional behavior with an onset potential of -60 mV for HER and an overpotential of 320 mV to achieve a current density of 10 mA cm for OER in 1 m KOH while maintaining robust stability. Moreover, the electrolysis cell using the catalyst only requires a low cell voltage of 1.73 V to achieve a current density of 10 mA cm and maintains the activity for more than 100 h when employing the Mo C/CS catalyst as both anode and cathode electrodes. Such high performance makes Mo C/CS a promising electrocatalyst for practical hydrogen production from water splitting.