Taking advantage of the self-assembling function of amino acids, cobaltalanine complexes are synthesized by straightforward process of chemical precipitation. Through a controllable calcination of the cobalt-alanine complexes, N-doped Co 3 O 4 nanostructures (N-Co 3 O 4 ) and N-doped CoO composites with amorphous carbon (N-CoO/C) are obtained. These N-doped cobalt oxide materials with novel porous nanostructures and minimal oxygen vacancies show a high and stable activity for the oxygen evolution reaction. Moreover, the influence of calcination temperature, electrolyte concentration, and electrode substrate to the reaction are compared and analyzed. The results of experiments and density functional theory calculations demonstrate that N-doping promotes the catalytic activity through improving electronic conductivity, increasing OH − adsorption strength, and accelerating reaction kinetics. Using a simple synthetic strategy, N-Co 3 O 4 reserves the structural advantages of micro/nanostructured complexes, showing exciting potential as a catalyst for the oxygen evolution reaction with good stability.

With the ever increasing demand for clean, sustainable energy, electrochemical supercapacitors with the advantages of high power density, high efficiency and long life expectancy have become one of the major devices for energy storage and power supply, and have found wide application in hybrid power sources, backup power sources, starting power for fuel cells and burst-power generation in electronic devices.

N,S co-doped 3D mesoporous carbon–Co3Si2O5(OH)4 composites are employed as electrodes together with activated carbon for pseudo-solid-state flexible electrochemical capacitors, which show a high performance.

are named as electrochemical double layer capacitors (EDLCs) and pseudocapacitors. [13][14][15] EDLCs produce capacitance from the electrostatic charge which is accumulated at electrode/electrolyte interface producing the electrostatic charge separation; besides, the ordinary electrode materials are carbon materials, such as activated carbon, graphene, and carbon nanotubes (Figure 1a). [16,17] Carbon-based materials, such as activated carbon, [18][19][20] carbon nanofibers, [21,22] carbon nanotubes, [23][24][25] and graphene, [26][27][28][29][30] present high surface areas, good electronic conductivities, and chemical stabilities. The other approach is pseudocapacitor, in which faradic processes are generated due to electroactive species (Figure 1b). The active materials in the electroactive species contain hydroxides, transition metal oxides, and conducting polymers. [31][32][33][34] Specifically, conducting polymers present high specific capacitance; however, their weaknesses are of high cost and poor cycling stability roots in their low conductivity. Beyond that, pseudocapacitive transition metal oxides serve as admirable supercapacitor electrodes. [35][36][37] Nonetheless, the poor cycling life and low energy density impose restrictions on their practical applications, especially for two electrode supercapacitor thus encouraged us to design new electrode materials from these pseudocapacitive metal oxides. In the meanwhile, the comprehensiveness of transition metal oxides/hydroxides and carbon-based materials led to high quality of performance and arose significant attention. [34,38,39] For example, on account of the superior pseudocapacitive performance, RuO 2 has attracted increasing attention, although it exhibits a limitation in practical applications due to its high cost. [40,41] Due to the fact, RuO 2 ·xH 2 O/carbon nanofiber composites obtained by Pico et al. present high specific capacitance and long cycle life. [42] Typically, for high-performance SCs, hollow structures were investigated to increase their active surface areas and porosity for efficient transportation. [43][44][45] In addition, hollow micro/nanostructured materials have proven their valuable applications in energy storage system (Li-ion batteries [46][47][48][49][50] and SCs [51][52][53][54] ) resulting from their shell functionality [55] and novel interior geometry. Especially, the hollow nanostructure presents a competent link between electrode materials and the electrolyte, which also can improve the electrochemical performance. [56] The hollow structure also possesses far more cavities, which works as an ''ion reservoir'' and ample room, in favor of lattice expansion. [57,58] So far, it is common to obtain hollow structures via template-method and water/oil/water (W/O/W) Electrochemical capacitors (supercapacitors, SCs), have been deemed to be one of the most promising powerful electrochemical energy storage devices, owing to that SCs have long cycle lives, high power densities, and fast recharge capabilities. Transition metal oxid...

The as-prepared AuNPs@silica/FFP (GSP) membrane displays strong and reusable performance for highly efficient water desalination and decontamination.

As the energy crisis turning out to be more and more serious, an interest in renewable energy sources is also increasing. [3] Researchers around the world have been devoting themselves to developing a high-performance electric energy storage material [4] to meet the demand for ecofriendly, sustainable, and low-cost energy. Among several kinds of electrical energy storage systems, lithiumion batteries have been developed as largescale energy storage units [5] and energy storage medium in electric vehicles, [6] smart grids, and other clean energy systems such as solar and wind since 1990s. [7] The lithium ion battery is identified as one of the ideal candidates to meet these requirements due to its desired energy density, superior voltage, and light weight. [8] However, extensive application of lithium ion batteries faces challenges related to the availability and cost of lithium. Scientists have their eyes on making sodium ion batteries as an alternative, because sodium is more abundant than lithium. Except that, it is also cheaper and easy to recover. [9] So nowadays, studying new kinds of electrode materials for lithium ion batteries and sodium ion batteries can be a rewarding work.During the last few decades, LiFePO 4 has attracted much attention, which was reported as a positive electrode for rechargeable lithium ion batteries first by Good-enough and co-workers in 1990s. [10] Nowadays, thousands of research publications have been authored on LiFePO 4 , [11] such as graphene-encapsulated LiFePO 4 composite, [12] pure LiFePO 4 , and LiFePO 4 /C, [13] 3D porous LiFePO 4 , [14] olivine LiFePO 4 , [15] mesoporous carboncoated LiFePO 4 , [16] graphene-modified LiFePO 4 , [17] LiFePO 4 / reduced graphene oxide hybrid, [18] and so on. LiFePO 4 owns favorable kinetics of the lithium intercalation/deintercalation process [19,20] and its nanocrystal size and shape can be easily controlled, [21] especially when it is complexed with carbon-based materials or other elements, the electrochemical properties of the composite material can be greatly improved. [22,23] It also has advantages of atop safety, environmental friendliness, affordability, as well as its comparatively reasonable electrochemical performance. [24][25][26][27] Until now, many researchers have examined LiFePO 4 as next generation cathode material. [28] Since FePO 4 also shows intrinsically poor ionic and electrical conductivity, small tap density which influences its electrochemical performance, [29] LiFePO 4 will not be further discussed in this article.High-performance electric energy storage material has recently developed due to the attention for sustainable development. As ecofriendly energy storage device, lithium ion batteries and sodium ion batteries deserve more concern today. FePO 4 and NaFePO 4 share similar advantages such as easy preparation, abundant, and inexpensive, so they can be ideal materials for lithium/sodium ion batteries. This review is focused on recent progresses in nanostructured FePO 4 /NaFePO 4 -based nanomaterial as cathode ma...

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The development of technology for solar interface evaporation has a significant meaning for the sustainable use of water resources in remote regions. However, establishing a solar evaporator with a high evaporation rate and favorable water treatment capabilities remains challenging. In this work, we reported a silver nanoparticle (AgNP)@carbonized cattail (CC)/polyvinyl alcohol (PVA) composite hydrogel (ACPH) membrane. Because of the successfully loaded AgNPs, which have a photothermal synergy with the CC, the ACPH-10 membrane obtained an excellent photothermal conversion performance. Additionally, the hydrophilicity of the ACPH-10 membrane ensures a sustainable water supply which is necessary for the improvement of the evaporation rate. Therefore, the ACPH-10 membrane achieves an evaporation rate of 1.66 kg m−2 h−1 and an efficiency of 88.0%, attributed to the remarkable photothermal conversion and water transmission. More importantly, the membrane exhibits superior purification ability in a variety of sewage. Pollutant removal rates in heavy metal and organic dye sewage have exceeded 99.8%. As a result, the ACPH membrane holds great promise for wastewater recovery and seawater desalination, which can aid in resolving the water crisis issue.