Photocatalytic CO 2 reduction into renewable hydrocarbon solar fuels is considered as a promising strategy to simultaneously address the global energy and environmental issues. In this study, a binary g-C 3 N 4 /ZnO photocatalytic system was constructed via a one-step facile calcination method and further used as photocatalysts for CO 2 reduction. It was shown that the as-prepared g-C 3 N 4 /ZnO photocatalytic system exhibited enhanced photocatalytic activity for CO 2 reduction by a factor of 2.3 compared with the pure g-C 3 N 4 , while maintaining the original selectivity of pure g-C 3 N 4 to convert CO 2 directly into CH 3 OH. For the first time, the coupling effect of ZnO responsible for the improved photoactivity of g-C 3 N 4 was fully illustrated and a direct Z-scheme mechanism rather than the conventional heterojunction-type mechanism was proposed to explain the better performances of g-C 3 N 4 /ZnO binary composite photocatalytic system. The enhancement of photocatalytic CO 2 reduction activity is attributed to the highly efficient ZnO-to-g-C 3 N 4 electron transfer occurring at the intimate contact interface between g-C 3 N 4 phase and ZnO phase. This work will provide new deep insights into the rational construction of g-C 3 N 4 -based photocatalytic system and the design of direct Z-scheme system without an electron mediator for photocatalytic CO 2 reduction reactions.Please do not adjust margins confirming the existence of the interfacial contact proposed above. The denoted lattice fringes with d spacing of 0.26 nm can be assigned to the (002) crystal plane of hexagonal wurtzite ZnO. 46 TOC Direct Z-scheme g-C 3 N 4 /ZnO binary composite photocatalytic system was constructed and exhibited enhanced photocatalytic CO 2 reduction activity than g-C 3 N 4 or ZnO.

Hierarchical porous TiO(2)-B with thin nanosheets is successfully synthesized. TiO(2)-B polymorph ensures fast insertion of Li-ion due to its pseudocapacitive mechanism. The thin nanosheet walls with porous structure allow exposure to electrolytes for facile ionic transport and interfacial reaction. The joint advantages endow this material with high reversible capacity, excellent cycling performance, and superior rate capability.

Advanced capabilities in electrical recording are essential for the treatment of heart-rhythm diseases. The most advanced technologies use flexible integrated electronics; however, the penetration of biological fluids into the underlying electronics and any ensuing electrochemical reactions pose significant safety risks. Here, we show that an ultrathin, leakage-free, biocompatible dielectric layer can completely seal an underlying layer of flexible electronics while allowing for electrophysiological measurements through capacitive coupling between tissue and the electronics, and thus without the need for direct metal contact. The resulting current-leakage levels and operational lifetimes are, respectively, four orders of magnitude smaller and between two and three orders of magnitude longer than those of any other flexible-electronics technology. Systematic electrophysiological studies with normal, paced and arrhythmic conditions in Langendorff hearts highlight the capabilities of the capacitive-coupling approach. Our technology provides a realistic pathway towards the broad applicability of biocompatible, flexible electronic implants.

One of the challenges in material science has been to prepare macro-or mesoporous zeolite. Although examples of their synthesis exist, there is a need for a facile yet versatile approach to such hierarchical structures. Here we report a concept for designing a single quaternary ammonium head amphiphilic template with strong ordered self-assembling ability through p-p stacking in hydrophobic side, which stabilizes the mesostructure to form singlecrystalline mesostructured zeolite nanosheets. The concept is demonstrated for the formation of a new type of MFI (zeolite framework code by International Zeolite Association) nanosheets joined with a 90°rotational boundary, which results in a mesoporous zeolite with highly specific surface area even after calcination. Low binding energies for this selfassembling system are supported by a theoretical analysis. A geometrical matching between the arrangement of aromatic groups and the zeolitic framework is speculated for the formation of single-crystalline MFI nanosheets.

The construction of highly efficient and stable Pt-free catalysts for electrochemical hydrogen generation is highly desirable. Herein, we demonstrate the first metal-phosphides-metal system consisting of Ru, NiP, and Ni, which forms unique multiheterogeneous Ni@NiP-Ru nanorods. Interestingly, a Ru modulation effects that promotes the desorption of H to achieve a moderate hydrogen adsorption energy (ΔG), and enables the formation of Ni@NiP nanorods via Ru-Ni coordination to enhance the conductivity was discovered. Due to its optimal ΔG, improved conductivity and rod-like morphology, this catalyst shows superior electrocatalytic HER performances in both acidic and alkaline conditions, which are superior to those of some recently reported phosphides and close to that of commercial 20% Pt/C. Such a design strategy is not limited to NiP and Ru but also may be extended to other similar phosphides and noble metals, providing a new promising approach and an alternative to Pt catalysts for electrocatalytic applications.

Materials that can serve as long-lived barriers to biofluids are essential to the development of any type of chronic electronic implant. Devices such as cardiac pacemakers and cochlear implants use bulk metal or ceramic packages as hermetic enclosures for the electronics. Emerging classes of flexible, biointegrated electronic systems demand similar levels of isolation from biofluids but with thin, compliant films that can simultaneously serve as biointerfaces for sensing and/or actuation while in contact with the soft, curved, and moving surfaces of target organs. This paper introduces a solution to this materials challenge that combines (i) ultrathin, pristine layers of silicon dioxide (SiO2) thermally grown on device-grade silicon wafers, and (ii) processing schemes that allow integration of these materials onto flexible electronic platforms. Accelerated lifetime tests suggest robust barrier characteristics on timescales that approach 70 y, in layers that are sufficiently thin (less than 1 μm) to avoid significant compromises in mechanical flexibility or in electrical interface fidelity. Detailed studies of temperature- and thickness-dependent electrical and physical properties reveal the key characteristics. Molecular simulations highlight essential aspects of the chemistry that governs interactions between the SiO2 and surrounding water. Examples of use with passive and active components in high-performance flexible electronic devices suggest broad utility in advanced chronic implants.

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Recent studies on nanoscale Bi-based photocatalysts including component adjustment, morphology control, heterojunction construction and surface modification are reviewed.