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Carbon materials with defect-rich structure are highly demanded for various electrochemical scenes, but encountering a conflict with the deteriorative intrinsic conductivity. Herein, we build a highway-mediated nanoarchitecture that consists of the ordered pseudographitic nanodomains among disordered highly nitrogen-doped segments through a supramolecular self-assembly strategy. The "order-in-disorder" nanosheet-like carbon obtained at 800 °C (O/D NSLC-800) achieves a tradeoff with high defect degree (21.9 at% of doped nitrogen) and compensated electrical conductivity simultaneously. As expected, symmetrical O/D NSLC-800 electrodes exhibit superior capacitive deionization (CDI) performance, including brackish water desalination (≈82 mgNaCl g−1 at a cell voltage of 1.6 V in a 1000 mg L−1 NaCl solution) and reusage of actual refining circulating cooling water, outperforming most of the reported state-of-the-art CDI electrodes. The implanted pseudographitic nanodomains lower the resistance and activation energy of charge transfer, which motivates the synergy of hosting sites of multiple nitrogen configurations. Our findings shed light on electrically conductive nanoarchitecture design of defect-rich materials for advanced electrochemical applications based on molecular-level modulation. Carbon materials are widely used in electrochemical technologies. However, their intrinsic conductivity deteriorates over time. Here the authors build a highway-mediated nanoarchitecture of ordered pseudographitic nanodomains to promote charge transfer for electrochemical ion capture. [ABSTRACT FROM AUTHOR]

Suffering from the susceptibility to decomposition, the potential electrochemical application of FeOCl has greatly been hindered. The rational design of the soft‐hard material interface can effectively address the challenge of stress concentration and thus decomposition that may occur in the electrodes during charging and discharging. Herein, interlayer structure manipulation of FeOCl/MXene using soft‐hard interface design method were conducted for electrochemical dechlorination. FeOCl was encapsulated in Ti3C2Tx MXene nanosheets by electrostatic self‐assembly layer by layer to form a soft‐hard mechanical hierarchical structure, in which Ti3C2Tx was used as flexible buffer layers to relieve the huge volume change of FeOCl during Cl− intercalation/deintercalation and constructed a conductive network for fast charge transfer. The CDI dechlorination system of FeOCl/Ti3C2Tx delivered outstanding Cl− adsorption capacity (158.47 ± 6.98 mg g−1), rate (6.07 ± 0.35 mg g−1 min−1), and stability (over 94.49 % in 30 cycles), and achieved considerable energy recovery (21.14 ± 0.25 %). The superior dechlorination performance was proved to originate from the Fe2+/Fe3+ topochemical transformation and the deformation constraint effect of Ti3C2Tx on FeOCl. Our interfacial design strategy enables a hard‐to‐soft integration capacity, which can serve as a universal technology for solving the traditional problem of electrode volume expansion. [ABSTRACT FROM AUTHOR]

Precise regulation on interfacial electronic coupling is essential to achieve efficient catalysts with tailored electrocatalytic behaviors but remains challenging. Herein, a straightforward topochemical strategy is presented to realize Co‐based heterostructured nanofiber stereoassembled with PO coupled nanosheet (CoHF/PO). By constructing well‐defined metal oxide/phosphide interface, prominent electron redistribution can be established via interfacial PO coupling, which is strongly correlated with the catalytic activities. Density functional theory calculations indicate that the rational interface engineering renders accelerated charge transfer and more importantly, optimized surface adsorption/desorption behaviors, contributing to boosted kinetics for both hydrogen evolution reaction and oxygen evolution reaction. Particularly, CoHF/PO featuring promoted intrinsic activity and accessible active sites exhibits intriguing activity and stability at higher current densities in alkaline media, surpassing commercial Pt/C and Ir/C. This study is expected to demonstrate noteworthy promise of covalent coupling toward modulated electronic environment and interface chemistry for electrocatalytic applications and beyond. [ABSTRACT FROM AUTHOR]

[Display omitted] • Bi 2 O 2 S 2D nanosheets films were prepared in-situ by one-step hydrothermal method. • [hk1] oriented Sb 2 S 3 NRs were epitaxially grown on Bi 2 S 3 transformed from Bi 2 O 2 S. • 2D/1D Bi 2 O 2 S/Sb 2 S 3 heterojunction constructed a rapid electron migration channel. • The TiO 2 /Bi 2 O 2 S/Sb 2 S 3 -annealed photoelectrode showed 4.37 mA/cm2 at 1.23 V RHE. Bismuth oxysulfide (Bi 2 O 2 S) is a layered material with high carrier mobility, excellent light absorption characteristic and good stability. However, there are few reports about the use of Bi 2 O 2 S in photoelectrochemical (PEC) water splitting. In this paper, Bi 2 O 2 S nanosheets (NSs) films were prepared on FTO substrates by one-step hydrothermal method, which broke the traditional powder state of Bi 2 O 2 S prepared. Based on the high lattice matching between antimony sulfide (Sb 2 S 3) and bismuth sulfide (Bi 2 S 3) obtained from the topological transformation of partial Bi 2 O 2 S, Sb 2 S 3 nanorods (NRs) with [hk1] predominant orientation were epitaxially grown on the surface of Bi 2 O 2 S to establish a transport channel for rapid carrier migration. Titanium dioxide (TiO 2) electron transport layer with oxygen vacancies was introduced into the back to capture and release electrons, further reducing the recombination rate. The photocurrent density of TiO 2 /Bi 2 O 2 S/Sb 2 S 3 -annealed photoelectrode at 1.23 V vs. RHE was 4.37 mA/cm2, which was 13.7 times that of monomer Bi 2 O 2 S. In addition, the TiO 2 /Bi 2 O 2 S/Sb 2 S 3 -annealed photoelectrode had lower charge transfer resistance and the IPCE value up to 48.22%. This study is of great significance for the application of Bi 2 O 2 S based photoelectrodes in the field of PEC water splitting. [ABSTRACT FROM AUTHOR]

[Display omitted] • Fluorinated CdS/MoS 2 /ZnS nanocatalyst for hydrogen production is prepared. • Zn(OH)F nanoflowers are used as a multifunctional platform during synthesis. • Zn(OH)F limits the growth of CdS/ZnS nanoparticles and supplies F− ions. • The rapid capture and transfer of charges by MoS 2 promotes hydrogen production. The design and synthesis of highly efficient photocatalysts for hydrogen production via morphological engineering and channel construction technology based on photogenerated carrier transfer is an effective method for solving the energy problem and reducing environmental pollution. However, developing inexpensive semiconductor catalysts with high photocatalytic hydrogen evolution activity remains a challenging task. Herein, fluorinated CdS/MoS 2 /ZnS nanoparticles (CMZS NPs-F) with a precise surface distribution were prepared using Zn(OH)F nanoflowers as a multifunctional platform, for the efficient photocatalytic hydrogen production. Zn(OH)F not only limited the growth of CdS/ZnS NPs, but also provided F− ions to accelerate the carrier interfaciale transfer. Meanwhile, the rapid capture and transfer of charges by MoS 2 increaed the hydrogen production rate of CMZS NPs-F to 11902 μmol·g−1·h−1, which was 13.9 times higher than that of CdS/ZnS. The results of experimental studies and density functional theory calculations that the observed increase in the hydrogen production rate was mainly due to the larger number of active sites, lower e-–h+ recombination efficiency and higher photogenerated charge transfer efficiency of CMZS NPs-F. This study provides deep insights into the photogenerated charge separation path and highly efficient catalytic hydrogen production. [ABSTRACT FROM AUTHOR]

Molybdenum disulfide (MoS 2) is heralded as an exemplary two-dimensional (2D) functional material, largely attributed to its distinctive layered structure. Upon forming heterojunctions with reducing species, MoS 2 displays remarkable photocatalytic properties. In this research, we fabricated a novel heterojunction photocatalyst, FeS/MoS 2 -0.05, through the integration of FeS with hollow MoS 2. This composite aims at the efficient photocatalytic reduction of hexavalent chromium (Cr(VI)). A comprehensive array of characterization techniques unveiled that MoS 2 flakes, dispersed on FeS, provide numerous active sites for photocatalysis at the heterojunction interface. The inclusion of FeS seemingly promotes the formation of sulfur vacancies on MoS 2. Consequently, this heterojunction catalyst exhibits photocatalytic activity surpassing pristine MoS 2 by a factor of 3.77. The augmented activity of the FeS/MoS 2 -0.05 catalyst is attributed chiefly to an internal electric field at the interface. This field enhances the facilitation of charge transfer and separation significantly. Density functional theory (DFT) calculations, coupled with experimental analyses, corroborate this observation. Additionally, DFT calculations indicate that sulfur vacancies act as pivotal sites for Cr(VI) adsorption. Significantly, the adsorption energy of Cr(VI) species shows enhanced favorability under acidic conditions. Our results suggest that the FeS/MoS 2 -0.05 heterojunction photocatalyst presents substantial potential for the remediation of Cr(VI)-contaminated wastewater. [Display omitted] • The FeS/MoS 2 -0.05 heterojunction photocatalysts exhibit superior photocatalytic activity in the photoreduction of Cr(VI). • The synergistic effects of surface sulfur vacancies and heterojunction interfaces in FeS/MoS 2 -0.05 heterojunction effectively promotes charge transfer and separation. • The charge density difference plot shows the transfer of electrons from FeS to MoS 2. [ABSTRACT FROM AUTHOR]

[Display omitted] • Bi/Bi 2 O 3 /TNAs were optimally prepared in situ on titanium foils. • Bi/Bi 2 O 3 /TNAs showed excellent visible-light photocatalytic activity to CIP degradation. • α-Bi 2 O 3 and Bi deposition improved optical and photoelectrochemical property of TNAs. • The internal electric field at heterojunction interface promoted charges transfer. • Photocatalytic mechanism and two main degradation pathways were proposed. The heterogeneous photocatalysis was considered as a sustainable and environmentally friendly technology to rapidly eliminate organic contaminants in water, but its practical application was severely limited by difficult recyclability, low visible-light utilization and high carriers recombination of traditional photocatalysts. Herein, the surface plasmonic Bi nanoparticles and α-Bi 2 O 3 co-modified TiO 2 nanotube arrays (Bi/Bi 2 O 3 /TNAs) were optimally prepared in situ on titanium foils. The interface interaction among TNAs, α-Bi 2 O 3 and Bi nanoparticles demonstrated the successful construction of tight ternary heterojunction. Bi/Bi 2 O 3 /TNAs effectively solved the recovery of traditional photocatalysts, and exhibited more excellent photocatalytic activity (90.3%) to ciprofloxacin (CIP) than TNAs (25.3 %). The enhancing photocatalytic activity was associated with the improved visible-light utilization and suppressed carriers recombination. The coexistence of inorganic anions and natural organic matters declined CIP removal owing to competing active sites or quenching radicals. The density functional theory calculations further demonstrated that the staggered energy levels caused the generation of an internal electric field at the heterojunction interface, which promoted charges transfer. Two main degradation pathways of CIP were proposed, and Bi/Bi 2 O 3 /TNAs photocatalytic system could realize the gradually detoxification of CIP. [ABSTRACT FROM AUTHOR]

[Display omitted] • Unique popcorn-like nanosphere structure endows abundant active sites. • DFT theoretical calculation reveal the transfer pathway of charges. • Hierarchical tandem heterojunctions promote the separation of carriers. • The H 2 production efficiency is 50 times higher than the unmodified material. • It offers a new method for green energy conversion and hydrogen energy separation. Heterojunction engineering is widely recognized as one of the most effective strategies for enhancing photocatalytic performance and suppressing photocorrosion by promoting efficient carrier separation and transfer. In this work, popcorn-like ZnCdS-MoS 2 @Co 3 O 4 nanospheres with large specific surface areas and hierarchical tandem heterojunctions were synthesized via one-pot in-situ self-assembly combined with hole-driven photodeposition. Based on the highly uniform dispersion of MoS 2 as an electron collector in the system and precise deposition of Co 3 O 4 as a photogenerated hole collector driven by photogenerated carriers at the hole enrichment position, it can efficiently catalyze the photocatalytic hydrogen evolution in water. Compared to ZnCdS, the optimized ZCS-M@0.5C exhibits a 50-fold increase in visible-light-driven hydrogen evolution efficiency, achieving 18.73 mmol·h−1·g−1 and maintaining stability after a 20-hour cycle test. Additionally, the apparent quantum yield reaches a remarkable 10.11% at 420 nm. Experimental characterization tests and differential charge density analysis have confirmed the efficient ability of Pt-like MoS 2 to induce electron separation and transportation, while p-type semiconductor Co 3 O 4 accumulates holes through the p-n junction. Both theoretical and experimental evidence show that the incorporation of dual-internal electric fields facilitates bi-directional charge separation and rapid transfer. The photocatalytic performance is improved through a synergistic effect involving hierarchical tandem heterojunctions. This work presents a novel approach to fabricating highly efficient photocatalysts with multi-heterojunctions through synergistic effects. [ABSTRACT FROM AUTHOR]

Unique porous ZnS-CdS-CoS x Reuleaux triangle nanosheets were prepared via a bimetallic precursor and ion-exchange process, achieving efficient photocatalytic H 2 production due to the synergistic effect of Z-scheme heterojunction and vacancy defects. [Display omitted] • Porous ZnS-CdS-CoS x Reuleaux triangle nanosheets are first reported. • Z-scheme heterojunction and S, Zn vacancies enable efficient charge separation. • CoS x provides abundant S 2 2- species as active sites for H 2 production. • Excellent HER rate (53.43 mmol·g−1·h−1) and AQE (30.8 % at 420 nm) are obtained. • Prominent H 2 -evolving stability attested by cycling and long-term tests. Photocatalytic water-splitting employing Z-scheme semiconductor heterojunction is a promising avenue to realize the efficient conversion and storage of renewable solar energy because of its space-separated reduction and oxidation sites, effective charge separation and transportation, as well as the stronger redox abilities of photogenerated carriers. Nevertheless, the efficiency of Z-scheme photocatalysts is often weakened by the insufficient coupling of components due to the stepwise hybridization processes. In this work, unique ZnS-CdS-CoS x porous Reuleaux triangle nanosheets with intimate Z-scheme hetero-interface and S, Zn vacancies were produced by using Zn 2 Co 3 (OH) 10 ·2H 2 O as the bimetallic precursor for subsequent sulfurization and Cd2+-exchange reaction. Noticeably, such a novel structure shows desirable features which suggest a promising photocatalyst for visible-light photocatalytic H 2 evolution, including superior charge-separating capability enabled by the Z-scheme charge transfer and synergetic charge-trapping effect of S, Zn vacancies, excellent light-harvesting capacity, abundant S 2 2− species as H 2 -evolving active sites, a large surface area, and good stability without obvious decline in activity after multiple cycling and long-term tests. The ZnS-CdS-CoS x heterojunction exhibits an outstanding visible-light-driven H 2 -evolving activity as high as 53.43 mmol·g−1·h−1, corresponding to a high apparent quantum efficiency of 30.8 % at 420 nm, far better than that of Pt-loaded CdS and a great deal of CdS-based photocatalysts reported in the literatures. The present work may shed new light on the designed synthesis of high-performance semiconductor heterojunction for sustainable solar utilization and environmental remediation. [ABSTRACT FROM AUTHOR]

Here we report a rational design and preparation of luminescent COFs via the synergetic interaction of electron-rich and electron-deficient moieties. 4,4′,4′-(1,3,5-triazine-2,4,6-triyl) trianiline (TTA) with the electron-deficient unit and 2,6-diformyl-4-methylphenol (Dp) with the electron-rich moiety and −OH group were employed to synthesize the imine-linked DpTTA-COF. The intramolecular charge transfer enables DpTTA-COF to present a strong solvent polarity-dependent color change, based on which a solvatochromic sensor was successfully established. We demonstrate an emission wavelength and intensity dual-mode photoluminescent sensor for the detection of trace water in organic solvents with good sensitivity, reversibility and stability. In addition, the dual-signal solvatochromic sensor is also capable for organic solvents decoding. This work proposes a new strategy for the design and preparation of COFs with fascinating solvatochromic effect. This strategy could extend the application field of COFs by the integration of functional groups, affinity, and structural selectivity. [Display omitted] • A push-pull type COFs have been designed for luminescent sensing. • This dual-signal mode probe is used for monitoring both of solvent molecules and trace water in organic solvents. • The probe shows superior sensing performance for trace water sensing in organic solvents. [ABSTRACT FROM AUTHOR]

[Display omitted] • The successful synthesis of hydrogen-bonded MCN/BOCH heterojunction systems. • Hydrogen bonding can act as a bridge to accelerate interfacial charge transfer. • MCN/BOCH heterojunction has synergistic degradation of SMX and Et-PABA. • SMX and Et-PABA as electron donors and acceptors to further accelerate charge transfer. The use of photocatalysis to remove pharmaceuticals and personal care products (PPCPs) is emerging as a promising method, but few studies have investigated the simultaneous degradation of multiple PPCPs. Here, we constructed a hydrogen-bonded bridged MIL-101(Cr)–NH 2 /BiOCl-OH (MCN/BOCH) system to degrade sulfamethoxazole and ethyl p-aminobenzoate alone or in combination. The MCN/BOCH system effectively removed two PPCPs under visible light and exerted a synergistic effect on degrading the combined pollutants. Meanwhile, the degradation products of the mixture changed significantly compared with that of a single pollutant, and the toxicity of the composite pollutants was significantly reduced through the combined effect of synergistic degradation. The bridging of hydrogen bonds effectively accelerated charge transfer at the heterojunction interface under visible light. Moreover, the separated redox side of the MCN/BOCH heterojunction system and the electron donor and acceptor effect of the two PPCPs significantly enhanced the synergistic photocatalytic degradation performance. This work might be useful for controllable designs of hydrogen-bonded photocatalysts for the treatment of complex PPCP pollution. [ABSTRACT FROM AUTHOR]

[Display omitted] • Oxygen vacancy Nanorods/Nanosheet Bi 2 MoO 6 homojunction photocatalyst were fabricated. • The internal electric field (IEF) in Bi 2 MoO 6 homojunctions promotes the separation and transition of photogenerated electrons and holes. • The oxygen vacancy Nanorods/Nanosheet Bi 2 MoO 6 homojunction displayed the enhanced photocatalytic activity under visible light irradiation for degrading phenol. • Occurrence of singlet oxygen as an active species in photocatalytic degradation of phenol. Homojunctions formed between two same semiconductors can notably facilitate charge transfer and separation. It is mainly used in solar cells to improve power conversion efficiency, and there is great potential for its application in photo-catalytic wastewater degradation. Herein, we designed an oxygen vacancy of Nanorods/Nanosheets Bi 2 MoO 6 homojunction photo-catalyst, prepared by calcining pure Bi 2 MoO 6 at high temperature and annealing it at the ambient temperature. Various characterization methods analyzed the chemical ingredient, microstructure, and optical characteristics. They are degrading phenol during visible illumination to survey the photo-catalytic performance of the homojunction. Density function theory (DFT) and other characterization methods demonstrate that the enhanced activity of the photo-catalyst is the efficient interfacial charge transfer and separation induced by the internal electric field and oxygen vacancies in the homojunction. This work provides a new strategy for constructing a novel homojunction to treat phenol wastewater. [ABSTRACT FROM AUTHOR]

Green bismuth-based photocatalysts have attracted extensive attention in the field of PPCPs photodegradation. The improved carrier separation efficiency still remains a key factor to enhance photocatalytic performance. Herein, N-doped biomass carbon quantum dots (N-CQDs) decorated p-n heterojunction photocatalyst BiO 2−x /BiOCl was prepared using a facile ion-etching strategy, and it displayed a markedly enhanced catalytic activity in the photodegradation of sulfonamide antibiotics. Calculated by the differential charge density, the doped N-CQDs could gather photogenerated electrons, which indicated that the introduction of N-CQDs into BiO 2−x /BiOCl would effectively inhibit the recombination of photogenerated charge carriers. In addition, photocatalytic performance and density functional theory (DFT) calculation results revealed that the photogenerated electrons tended to transfer from p-BiOCl to n-BiO 2−x through N-CQDs, which could generate ·O 2 - and photogenerated h+ to oxidize the target pollutants. Benefiting from the synergistic effect of accelerated separation of e--h+ in p-n heterojunction and the electron-rich performance of N-CQDs, the superb TOC removal efficiencies (89.40% within 120 min visible-light irradiation) and toxicity reduction performance of photodegradation intermediates were achieved. As a consequence, this work will provide a design of high-quality photocatalysts and a green-promising strategy for bismuth-based photocatalysts in the water treatment of PPCPs. [Display omitted] • N-CQDs/BiO 2−x /BiOCl (BBN) photocatalyst was prepared by ion-etching methods. • The doped N-CQDs act as an electron acceptor to effectively suppress the recombination of e--h+. • DFT calculation was used to study the charge transfer mechanisms. • The synergistic effect of p-n heterojunction and N-CQDs promoted the SMX photodegradation. [ABSTRACT FROM AUTHOR]