Efficient degradation of micropollutants in CoCaAl-LDO/peracetic acid (PAA) system: An organic radical dominant degradation process.

As a novel strategy, peracetic acid (PAA) based advanced oxidation processes (AOPs) are being used in micropollutant elimination due to their high oxidation and low toxicity. In this study, CoCaAl-LDO as a kind of layered double oxides (LDOs) was successfully synthesized, and it is the first time to apply CoCaAl-LDO for activating PAA. The CoCaAl-LDO/PAA system showed excellent removal efficiencies for various micropollutants with removal ratios ranging from 90.

In situ organic Fenton-like catalysis triggered by anodic polymeric intermediates for electrochemical water purification.

Organic Fenton-like catalysis has been recently developed for water purification, but redox-active compounds have to be ex situ added as oxidant activators, causing secondary pollution problem. Electrochemical oxidation is widely used for pollutant degradation, but suffers from severe electrode fouling caused by high-resistance polymeric intermediates. Herein, we develop an in situ organic Fenton-like catalysis by using the redox-active polymeric intermediates, e.

Phase Engineering of Iron-Cobalt Sulfides for Zn-Air and Na-Ion Batteries.

Rechargeable batteries are promising platforms for sustainable development of energy conversion and storage technologies. Highly efficient multifunctional electrodes based on bimetallic sulfides for rechargeable batteries are extremely desirable but still challenging to tailor with controllable phase and structure. Here, we report a colloidal strategy to fabricate FeCo-based bimetallic sulfides on reduced graphene oxide (rGO), which are expected to display highly efficient oxygen electrocatalysis and sodium storage performances.

Stable Electrochemical Determination of Dopamine by a Fluorine-Terminated {001}-Exposed TiO Single Crystal Sensor.

Photochemical oxidation is able to effectively regenerate the fouled electrode in electrochemical pollutant monitoring, while its regeneration capacity is limited by the surface-bound hydroxyl radical speciation with low activity and mobility, which is attributed to the dissociated water adsorption on hydrophilic metal oxides. In this work, fluorine-terminated {001}-exposed TiO single crystals (F-TiO) are rationally designed to construct an Au-based electrochemical sensor (Au/F-TiO) for dopamine (DA) detection in different matrices. The Au/F-TiO sensor exhibits an efficient and stable detection capacity in both environmental and biological samples.

Degradation of benzoic acid in an advanced oxidation process: The effects of reducing agents.

Fenton reaction is widely used for hazardous pollutant degradation. Reducing agents (RAs) have been proven to be efficient in promoting the generation of HO• in Fenton reaction by accelerating the redox cycle of Fe/Fe. However, the roles of different RAs in Fenton reaction remain unrevealed.

Photochemical Protection of Reactive Sites on Defective TiO Surface for Electrochemical Water Treatment.

The electrode is the key in electrochemical process for water and wastewater treatment. Many nonstoichiometric metal oxides are active electrode materials but have poor stability under strong anodic polarization due to their susceptible nature of the oxygen vacancies on surface and subsurface as defective reactive sites. In this work, a novel photochemical protecting strategy is proposed to stabilize the defective reactive sites on the TiO surface and subsurface for long-term anodic oxidation of pollutants.

Photo-assisted electrochemical detection of bisphenol A in water samples by renewable {001}-exposed TiO single crystals.

Bisphenol A (BPA) is a semi-persistent environmental endocrine disrupter and widely present in aqueous environments. Electrochemical detection is an effective method to monitor pollutants like BPA in aqueous environments. However, the electrode fouling from anodic polymeric products is one main barrier of electrochemical sensors for their practical applications.

Electrochemical Sensing of Bisphenol A on Facet-Tailored TiO Single Crystals Engineered by Inorganic-Framework Molecular Imprinting Sites.

Noble metals, nanostructured carbon, and their hybrids are widely used for electrochemical detection of persistent organic pollutants. However, despite of the rapid detection process and high accuracy, these materials generally suffer from high costs, metallic impurity, heterogeneity, irreversible adsorption and poor sensitivity. Herein, the high-energy {001}-exposed TiO single crystals with specific inorganic-framework molecular recognition ability was prepared as the electrode material to detect bisphenol A (BPA), a typical and widely present organic pollutant in the environment.

Photochemical Anti-Fouling Approach for Electrochemical Pollutant Degradation on Facet-Tailored TiO Single Crystals.

Electrochemical degradation of refractory pollutants at low bias before oxygen evolution exhibits high current efficiency and low energy consumption, but its severe electrode fouling largely limits practical applications. In this work, a new antifouling strategy was developed and validated for electrochemical pollutant degradation by photochemical oxidation on facet-tailored {001}-exposed TiO single crystals. Electrode fouling from anodic polymers at a low bias was greatly relieved by the free ·OH-mediated photocatalysis under UV irradiation, thus efficient and stable degradation of bisphenol A, a typical environmental endocrine disrupter, and treatment of landfill leachate were accomplished without remarkable oxygen evolution in synergistic photoassisted electrochemical system.

Efficient Electrochemical Reduction of Nitrobenzene by Defect-Engineered TiO2-x Single Crystals.

TiO2 is a typical semiconductor and has been extensively used as an effective photocatalyst for environmental pollution control. But it could not be used as an electrochemical reductive catalyst because of its low electric conductivity and electrocatalytic activity. In this work, however, we demonstrate that TiO2 can act as an excellent cathodic electrocatalyst when its crystal shape, exposed facet and oxygen-stoichiometry are finely tailored by the local geometric and electronic structures.

Degradation of refractory pollutants under solar light irradiation by a robust and self-protected ZnO/CdS/TiO2 hybrid photocatalyst.

Photocatalyst plays a vital role in the photochemical water treatment. To improve the visible-light photoactivity of TiO2 for refractory pollutant degradation, CdS/TiO2 hybrids with different nanostructures have been prepared, but usually suffer from a low photocatalytic degradation efficiency and a rapid photocorrosion. In this work, we developed a synergistic ZnO/CdS/TiO2 hybrid, which could act as a robust and self-protected photocatalyst for water purification without additional sacrificial reagents.

Defective titanium dioxide single crystals exposed by high-energy {001} facets for efficient oxygen reduction.

The cathodic material plays an essential role in oxygen reduction reaction for energy conversion and storage systems. Titanium dioxide, as a semiconductor material, is usually not recognized as an efficient oxygen reduction electrocatalyst owning to its low conductivity and poor reactivity. Here we demonstrate that nano-structured titanium dioxide, self-doped by oxygen vacancies and selectively exposed with the high-energy {001} facets, exhibits a surprisingly competitive oxygen reduction activity, excellent durability and superior tolerance to methanol.

Synthesis of Pt-Loaded Self-Interspersed Anatase TiO2 with a Large Fraction of (001) Facets for Efficient Photocatalytic Nitrobenzene Degradation.

TiO2 is capable of directly utilizing solar energy for sustainable energy harvest and water purification. Facet-dependent performance of TiO2 has attracted enormous interests due to its tunable photocatalytic activity toward photoredox transformations, but information about the noble-metal-loaded TiO2 for its facet-dependent photocatalytic performance, especially in pollutant degradation systems, is limited. In this work, inspired by our previous theoretical calculations about the roles of the crystal surface in Pt-loaded TiO2 in its enhanced photocatalytic capacity, TiO2 nanocrystals with interspersed polyhedron nanostructures and coexposed (001) and (101) surfaces as a support of Pt nanoparticles are prepared in a simple and relatively green route.

Roles of Crystal Surface in Pt-Loaded Titania for Photocatalytic Conversion of Organic Pollutants: A First-Principle Theoretical Calculation.

Titania modified with nanosized metallic clusters is found to substantially enhance its photocatalytic capacity for renewable energy generation and environmental purification, but the underlying mechanism, especially the roles of crystal surface in noble-metal-loaded TiO2, remain unclear. In this work, such roles in the Pt-loaded anatase TiO2 for the photocatalytic conversion of nitrobenzene (NB), a model pollutant, are explored by first-principle calculations. The theoretical calculations reveal that the Pt-TiO2 complex has a higher catalytic activity toward NB conversion than pure Pt clusters, and the (001) facets of TiO2 in this complex tend to accumulate more positively charged holes and thus have a higher photocatalytic activity than the (101) facets.

Light-driven microbial dissimilatory electron transfer to hematite.

The ability of dissimilatory metal-reducing microorganisms (DMRM) to conduct extracellular electron transfer with conductive cellular components grants them great potential for bioenergy and environmental applications. Crystalline Fe(III) oxide, a type of widespread electron acceptor for DMRM in nature, can be excited by light for photocatalysis and microbial culture-mediated photocurrent production. However, the feasibility of direct electron transfer from living cells to light-excited Fe(III) oxides has not been well documented and the cellular physiology in this process has not been clarified.