A vertically aligned ZnO/ZnS core/shell nanowire array with type II band alignment was directly synthesized on an indium-tin-oxide glass substrate and the photovoltaic effect of the nanowire array was investigated. The epitaxial relationship, wurtzite (0001) matching zinc-blende (111), was observed in the ZnO/ZnS nano-heterostructure. ZnS coating is found to quench the photoluminescence of ZnO nanowires but enhance the photocurrent with faster response in the photovoltaic device, indicating improvement in charge separation and collection in the type II core/shell nanowire.

Nevertheless, large-scale and low-cost application of these technologies require further development of many key functional materials. Mesoporous nanomaterials show many architecture-dependent merits, stemming from the high surface areas, large pore sizes, and rich pore structures. [11-18] To be specific, high surface area could offer rich active sites for surface-related processes, such as surface adsorption/desorption and redox reactions. [19-23] Large pore sizes are particularly important for encapsulating guest materials and accommodating mechanical strains during the electrochemical processes. [14,24-26] Tunable pore structures offer great opportunities for the mass transport through the bulk of the material, thus tailoring the number of accessible active sites, surmounting the diffusion restriction in microporous or nonporous materials. [27] Here, we provide a comprehensive review of the development of mesoporous nanomaterials for electrochemical energy conversion and storage. First, a brief summary of synthetic methods for mesoporous nanomaterials is provided. The emphasis is placed on the preparation principles and formation mechanisms for fine tailoring of mesoporous nanomaterials over the particle sizes, pore sizes, and nanostructures. Afterward, we further discuss the applications as electrode materials for LIBs, SCs, water splitting devices, and fuel cells. Finally, we end this review with a perspective on the possible development directions and challenges of mesoporous nanomaterials for electrochemical energy-related applications. Mesoporous materials have attracted considerable attention because of their distinctive properties, including high surface areas, large pore sizes, tunable pore structures, controllable chemical compositions, and abundant forms of composite materials. During the last decade, there has been increasing research interest in constructing advanced mesoporous nanomaterials possessing short and open channels with efficient mass diffusion capability and rich accessible active sites for electrochemical energy conversion and storage. Here, the synthesis, structures, and energy-related applications of mesoporous nanomaterials are the main focus. After a brief summary of synthetic methods of mesoporous nanostructures, the delicate design and construction of mesoporous nanomaterials are described in detail through precise tailoring of the particle sizes, pore sizes, and nanostructures. Afterward, their applications as electrode materials for lithium-ion batteries, supercapacitors, water-splitting electrolyzers, and fuel cells are discussed. Finally, the possible development directions and challenges of mesoporous nanomaterials for electrochemical energy conversion and storage are proposed.

No abstract

Mesoporous core-shell nanostructures with controllable ultra-large open channels in their nanoshells are of great interest. However, soft template-directed cooperative assembly to mesoporous nanoshells with highly accessible pores larger than 30 nm, or even above 50 nm into macroporous range, remains a significant challenge. Herein we report a general approach for precisely tailored coating of hierarchically macro-/mesoporous polymer and carbon shells, possessing highly accessible radial channels with extremely wide pore size distribution from ca. 10 nm to ca. 200 nm, on diverse functional materials. This strategy creates opportunities to tailor the interfacial assembly of irregular mesostructured nanounits on core materials and generate various core-shell nanomaterials with controllable pore architectures. The obtained Fe,N-doped macro-/mesoporous carbon nanoshells show enhanced electrochemical performance for the oxygen reduction reaction in alkaline condition.

No abstract