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Carbon encapsulated porous Sn/Sn4P3 (Sn/Sn4P3@C) composite is conveniently prepared by one-step electrochemical dealloying of Sn80P20 alloy in mild conditions followed by growing one carbon layer. Controllable dealloying of the Sn80P20 alloy results in the formation of bicontinuous spongy Sn4P3 nanostructure with a part of residued metallic Sn atoms embedded in the porous skeleton. A uniform carbon layer is deposited on the nanoporous Sn/Sn4P3 to prevent the nanostructure’s pulverizing and agglomerating during lithium ion insertion/extraction. Upon double conductivity modification from metallic Sn matrix and carbon layer, the as-made composite displays superior lithium-storage performances with much higher specific capacity as well as better cycling stability compared with pure porous Sn4P3. It offers a specific capacity of 837 mA h g−1 after 100 cycles at a rate of 100 mA g−1. Even after 700 cycles at the higher rate of 1000 mA g−1, the specific capacity still maintains as high as 589 mA h g−1. The Sn/Sn4P3@C material possesses promising application potential as an alternative anode in the lithium storage fields.

Nanoporous Ge/Cu3Ge composite is fabricated simply through selective dealloying of GeCuAl precursor alloy in dilute alkaline solution. The as-made Ge/Cu3Ge is characterized by three dimensional (3D) bicontinuous network nanostructure which comprises of substantial nanoscale pore voids and ligaments. Owing to the 3D porous architecture and the introduction of well-conductive Cu3Ge, the lithium storage performances of Ge are dramatically enhanced in terms of higher cycling stability and superior rate performance. Nanoporous Ge/Cu3Ge anode delivers steady capacities above 1000 mA h g−1 upon cycling for 70 loops at 400 mA g−1. In particular, after 300 cycles at the high rate of 3200 mA g−1 the capacity retention for Ge/Cu3Ge is able to reach a maximum of 99.3%. On the contrary, the pure nanoporous Ge encounters severe capacity decay. In view of the outstanding energy storage performances and easy preparation, nanoporous Ge/Cu3Ge exhibits great application potential as an advanced anode in lithium storage related technologies.

Nanoporous Si@TiO2 composites with the unique core-shell architecture are conveniently fabricated through one-step selective dealloying of SiTiAl ternary alloy under mild conditions. The as-prepared composites consist of bimodal Si network skeleton as the core and interconnected TiO2 nanosponge layer as the shell uniformly distribute on the Si surface to form the porous core-shelled structure. The nanoporous TiO2 as the outer protective layer not only reduce the violent volume change of electrode materials for stable cycling performance but also shorten the diffusion distance of Li+ for high rate capacities. The inner bimodal porous Si possesses an open bicontinuous network structure that can provide the enough empty space and robust backbone to relax the volume variation of composite and guarantee the sufficient electrode-electrolyte contact area. As a result, the optimized nanoporous Si@TiO2 composite delivers the reversible capacity of 1338.1 and 1174.4 mA h g−1 at the current densities of 200 and 1000 mA g−1 after continuous tests for 120 and 100 cycles, respectively. With the advantages of easy preparation, unique architecture, and high lithium storage performances, the porous core-shelled Si@TiO2 composites demonstrate the promising application potential as an anode material for LIBs.

The design and fabrication of highly active and durable catalysts for the ammonia borane (AB) hydrolysis has been one of significant issues in the application of green and economic hydrogen energy. Nanoporous (NP) PtCo/Co3O4 composites are straightforwardly fabricated by selectively etching Al atoms followed by removing Co atoms from the PtCoAl precursor alloy. By controlling the second-step dealloying, the NP-PtCo/Co3O4 composites evolved into pure nanoporous structure with Co3O4 nanosheets on the surface gradually disappeared as well different Pt/Co ratios resulted. Compared with NP-Pt and pure Co3O4 catalysts, the NP-PtCo/Co3O4 composites with different Pt/Co ratios exhibit markedly enhanced catalytic activity for the hydrolysis of AB. NP-Pt40Co60 composite with some Co3O4 nanosheets anchored on the surface shows the higher catalytic activity compared to other several samples with different Pt contents, exhibiting a high initial turnover frequency of 131mol H2 min-1 (mol Pt)-1. Meanwhile, the recyclability tests indicate that NP-Pt40Co60 composite retained 65% of the initial catalytic activity after the fifth run of hydrolysis. Therefore, the high catalytic activity and good durability render the as-made composite as a powerful catalyst candidate for the hydrolytic dehydrogenation of AB in the practical applications.

Mn3O4@graphene (Mn3O4@G) nanocomposite is easily fabricated through a facile preparation of Mn3O4 octahedra by dealloying MnAl alloy and a following reduction of coassembled aggregates of Mn3O4 octahedra and graphene oxide. Benefitting from the distinctive nanostructure and the hybridization with well-conductive graphene, the capacity retentions of Mn3O4@G are dramatically improved from 25.5 to 58.0% after 100 cycles at 300mAg-1 and from 15.8 to 43.8% after 200 cycles at 1000mAg-1, respectively. Even the current rates reach up to 2000 and 3000mAg-1, Mn3O4@G electrode could still hold the highly stable capacities around 520 and 430mAhg-1, respectively. On account of the superiorities of high electrochemical performances and easy preparation, the Mn3O4@G composite shows encouraging application potential to be an advanced anode material for lithium storage.

Fe 3 O 4 octahedra embedded in conductive nanoporous copper (NPC) network are straightforwardly fabricated by means of alloy refining followed by facile electroless dealloying in mild condition. During selectively dissolving the Al from FeCuAl alloy, the residual Cu atoms assemble to form sponge-like nanostructure, meanwhile the Fe atoms undergo spontaneous oxidation and aggregation to grow into Fe 3 O 4 octahedra travelled through NPC network. Owing to the combination of conductive NPC network, Fe 3 O 4 octahedra exhibit dramatically enhanced lithium storage performances with excellent reversible capacity, enhanced rate performance, as well outstanding cyclability compared with pure Fe 3 O 4 octahedra. Especially, Fe 3 O 4 /Cu nanocomposite shows superior cycling stability with the excellent reversible capacity of 664.0 and 512.6 mA h g −1 retained over 500 cycles at the current densities of 300 and 1000 mA g −1 , respectively. Moreover, it shows good rate capability even when cycled at 1000 mA g −1 . With the advantages of exceptional performances and facile preparation, the as-made Fe 3 O 4 /Cu nanocomposite shows prospective application potential as an advanced anode material in lithium ion batteries.

Nanoporous (NP) PdCu alloy is easily fabricated by dealloying PdCuAl ternary alloy in dilute sulfuric acid. Selectively dissolving Al from PdCuAl alloy generates the three-dimensional uniform nanosponge architecture with narrow ligament size distribution. Benefitting from the unique nanoporous architecture and the alloying effect, the as-made NP-PdCu exhibits outstanding sensing performance towards the detection of hydrogen peroxide (H2O2) and glucose. Compared with NP-Pd and commercial Pd/C catalysts, the NP-PdCu alloy presents high sensitivity, wide linear range of 0.1–2.0 mM, low detection limit of 2.1 μM, and long-term stability toward H2O2 detection. In addition, the NP-PdCu can efficiently detect glucose in a wide concentration range (1–30 mM) with the low detection limit of 1.9 μM. Moreover, the NP-PdCu exhibits good anti-interference toward ascorbic acid, uric acid, and dopamine. Characterized by easy preparation, unique electrocatalytic activity, and high structure stability, the NP-PdCu alloy possesses great application prospect to construct platform for electrochemical sensing.

Nanoporous Ge/Cu

Carbon encapsulated porous Sn/Sn

Nanoporous Si@TiO

Hierarchical nanoporous platinum-copper (hnp-PtCu) alloy nanoflowers with bimodal pore/ligament size are easily fabricated by selectively dissolving Al atoms and part of Cu atoms from PtCuAl ternary alloy. The dealloyed samples consist of cross-linking porous nanoflowers with interconnected network skeleton and hollow channels penetrated. Hnp-PtCu alloy nanoflowers with different compositions exhibit dramatically enhanced catalytic activities toward the hydrolysis of ammonia borane (AB) compared with their monometallic components. The hnp-Pt35Cu65 alloy shows superior catalytic performance than the other hnp-PtCu catalysts with an initial much higher turnover frequency of 108 mol H2 min-1 (mol Pt)-1. Moreover, the hnp-Pt35Cu65 displays excellent structure stability even after the five runs for the AB hydrolysis. The as-made hnp-PtCu catalysts hold promising application potential toward the AB hydrolysis with the advantages of facile preparation, high yielding, superior catalytic activity, and high structure durability.

Tin sulfide/graphene nanocomposite with hexagonal tin sulfide (SnS2) nanoplates anchored on reduced graphene oxide (RGO) nanosheets was easily synthesized by one-step controllable hydrothermal growth followed by mild reduction. The SnS2 hexagonal-plates distributed tightly and uniformly on the RGO support in a more favorable face-to-face (FTF) manner. The formation of SnS2 nanoplates with hexagonal morphology may result from the accelerating growth of six energetically equivalent high-index (1 1 0) crystal planes and prohibiting growth of the (0 0 1) crystal plane on graphene. The FTF architecture is beneficial for the optimal electric contact efficiency of SnS2 nanoplates with RGO matrix, thus leading to the greatly enhanced electrochemical performance of SnS2/RGO composite than bare SnS2. The graphene-constructed two-dimensional integrated conductive networks minimize the transport paths of electrons and Na ions between electrode and electrolyte as well as accommodate the mechanical strain during long term cyclic. The SnS2/RGO composite exhibits great application potential as an anode for sodium ion batteries with the advantages of unique structure and superior sodium storage performance.

Mn

Nanoporous (NP) PdCu alloy is easily fabricated by dealloying PdCuAl ternary alloy in dilute sulfuric acid. Selectively dissolving Al from PdCuAl alloy generates the three-dimensional uniform nanosponge architecture with narrow ligament size distribution. Benefitting from the unique nanoporous architecture and the alloying effect, the as-made NP-PdCu exhibits outstanding sensing performance towards the detection of hydrogen peroxide (H