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The positive relationship between knowledge transfer and knowledge innovation is recognized by most scholars, while knowledge heterogeneity, as a knowledge situation of the enterprise organization, affects knowledge transfer within enterprise organizations. Therefore, as a state, knowledge transfer can be regarded as a result of knowledge heterogeneity, and it becomes the intermediary state between knowledge heterogeneity and knowledge innovation. The organizational structure of individuals within an enterprise organization may affect these three elements and their interrelationships. In this paper, data are collected by means of on-the-spot investigation and a network questionnaire for analysis. The results show that the microstructure state of the individual in the enterprise organization plays a moderating role for the first three elements. The lower that the micro-restriction of the individual is, the more favorable the knowledge heterogeneity is for the inverted U-shaped impact of knowledge transfer and knowledge innovation and the more favorable the occurrence of knowledge innovation. [ABSTRACT FROM AUTHOR]

The article titled "Wastewater Treatment: Functional Materials and Advanced Technology" discusses the issue of water pollution caused by the increase in wastewater discharge and the emergence of new contaminants. The article introduces a Special Issue that focuses on feasible methods and insights for addressing these challenges. The Special Issue includes 34 publications that cover topics such as functional adsorption materials, ion sieves, and oxidation/reduction materials for various contaminants. The article also suggests future research directions, including the application of treatment methods to real wastewater, the development of efficient materials for emerging pollutants, and the consideration of economic factors in wastewater treatment. [Extracted from the article]

1,8-naphthalene anhydride (1,8-NA) is a common polycyclic aromatic hydrocarbons (PAHs) which are the most important light absorbed-organic aerosols (BrC) in atmospheric. 1,8-NA can generate different ROSs (·OH, ·O 2 -, H 2 O 2 , 1O 2) under the visible light irradiation. According to the results of DFT simulation and band structure analysis, 1,8-NA has the semiconductor characteristic, and the electrons of it can be excited from acid anhydride part to naphthalene ring part. Meanwhile, a built-in electric field exists between the acid anhydride and the naphthalene ring because of the molecular polarization of 1,8-NA. This electric field could promote the separation and migration of carriers. Therefore, electrons can easily be transferred to O 2 and produce ROS. The properties and mechanism of photocatalytic O 2 activation by atmospheric aerosol component 1, 8-NA were studied for the first time, which provided good support for further understanding of atmospheric photochemical mechanism. [Display omitted] • The photocatalytic activation of O 2 by 1,8- NA is studied for the first time. • The possible photocatalytic mechanism is discussed based on the experimental and theoretical results. • A built-in electric field between the anhydride and the naphthalene ring plays an important role in the photocatalysis process. • The photocatalytic activity of ROS by 1, 8-NA is superior to that of conventional organic photocatalysts g-C 3 N 4. [ABSTRACT FROM AUTHOR]

In this study, a novel Z-scheme +II-type ternary heterojunction nanocomposite was prepared by one-step solvothermal method using g-C 3 N 4 , FeS 2 and Fe 2 O 3 as raw materials. The scavenger test and electron spin resonance spectroscopy show that O 2 − is the main oxidizing free radical in the photocatalytic system. Finally, TC are mineralized into CO 2 and water. [Display omitted] • Z-scheme + II-type ternary heterojunction nanocomposite is elaborately designed to degradation of TC. • The O 2 − is the main active species participating in the Z-scheme + II-type degradation process. • Strong evidence of Z-scheme + II-type charge transfer pathway was verified by EPR analysis. • The possible degradation pathways and intermediates in TC were identified by LC–MS analysis. In this study, a novel Z-scheme + II-type ternary heterojunction nanocomposite was prepared by one-step solvothermal method using g-C 3 N 4 , FeS 2 and Fe 2 O 3 as raw materials. The successful preparation of this ternary heterojunction was confirmed by the structural analysis and the surface morphology study. Compared with g-C 3 N 4 , the ternary photocatalyst showed excellent photocatalytic performance for the degradation of tetracycline (TC). The enhancement of photocatalytic activity is mainly due to the increase of light absorption capacity, effective separation of carrier in space, and increase of electron transfer channels in this Z-Scheme + II-type composite system. The scavenger test and electron spin resonance spectroscopy show that O 2 − is the main oxidizing free radical in the photocatalytic system. Based on liquid chromatograph-mass spectrometer, a possible degradation pathway of TC was proposed. This study opens up a new idea for the design and synthesis of efficient Z-Scheme + II-type photocatalysts for environmental purification. [ABSTRACT FROM AUTHOR]

This study demonstrated for the first time that the presence of Brønsted acidic sites on the surface of clay minerals is conducive to the formation of N vacancies and dopant O in carbon nitride composites (CNM-30). The synergistic effect of N vacancy and doped O increases the specific surface area of CNM-30, enhances the electron-hole separation and transport efficiency, and ultimately makes CNM-30 produce more reactive oxygen species to degrade NO. [Display omitted] • Acid treatment and high-temperature calcination control to form Brønsted acidic sites on the surface of mullite. • Brønsted acidic site provides proton to improve g-C 3 N 4 structure. • The effect of oxygen doping and nitrogen vacancies accelerates the separation of charges. • Efficient degradation of NO, Rhodamine B, and tetracycline by reactive oxygen species. Clay minerals are considered promising semiconductor carrier materials due to their unique physical and chemical properties. However, the exact mechanism by which clay minerals interact with semiconductor materials remains unknown. To this end, the present study was conducted to explore the formation of Brønsted acidic sites on the surface of mullite by modulating the cation types in mullite. It was hereby demonstrated for the first time that the presence of Brønsted acidic sites on the surface of clay minerals is conducive to the formation of N vacancies and dopant O in carbon nitride composites (CNM-30). The synergistic effect of N vacancy and doped O increases the specific surface area of CNM-30, enhances the electron-hole separation and transport efficiency, and ultimately makes CNM-30 produce more reactive oxygen species. CNM-30 possesses excellent degradation ability for gaseous phase pollutants (such as NO) and high concentration liquid phase pollutants (such as RhB and TC). Overall, this paper presents a new perspective on the design and development of semiconductor materials based on clay minerals. [ABSTRACT FROM AUTHOR]

Melem is the basic structural unit of g-C 3 N 4. When directly utilized as a photocatalyst, the separation efficiency of photogenerated electron-hole pairs is low. In this study, we constructed a Melem-based all-organic heterojunction (PICN) by reacting the -NH 2 at the terminal of the Melem unit with the anhydride of PDA. The photocatalytic efficiency for H 2 O 2 production of the heterojunction is 4.2 times that of CN. Introducing -Cl at the bay position of PDI further enhances the photocatalytic H 2 O 2 production efficiency by 1.6 times. This enhancement is attributed to the introduction of -Cl, which not only broadens the UV–visible light absorption range of the sample but also improves the interface electron transfer efficiency between Melem and PDICl. Moreover, the introduction of -Cl can also reduce the overpotential of the O 2 reduction reaction on the surface of the sample. These novel findings may provide insights for the design of organic heterojunction photocatalysts. [Display omitted] • In this study, an all-organic heterojunction photocatalyst (PICN) was constructed by amidation reaction of PDA and Melem. • The bay -Cl substitution of PDI enhances the interfacial electron transfer between Melem and PDI. • In the absence of sacrificial agents, the H 2 O 2 yield of PI Cl CN under visible light is 1.6 times that of PICN. [ABSTRACT FROM AUTHOR]

The scanning-tunneling-microscope-induced luminescence emerges recently as an incisive tool to measure the molecular properties down to the single-molecule level. The rapid experimental progress is far ahead of the theoretical effort to the observed phenomena. Such incompetence leads to a significant difficulty in quantitatively assigning the observed feature of the fluorescence spectrum to the structure and dynamics of a single molecule. This work is devoted to revealing the microscopic origin of the molecular excitation via inelastic scattering of the tunneling electrons in the scanning tunneling microscope. The theory proposed here excludes the inelastic electron scattering as the origin of the observed larger photon-counting rate at the positive bias than that at the negative bias voltage. [ABSTRACT FROM AUTHOR]

This study focuses on the generation of circular polarization (CP) in a small-sized ground plane by using ground-mode tuning (GMT) technique. The proposed antenna is composed of two branches, so that it can simultaneously excite two orthogonal modes of the ground plane for radiation. Two metal strips at the ends of the ground plane are adopted as GMT structures, and the dominant modes along the length and width of the ground plane can be controlled by tuning the property of the shorting pins, conveniently. Both simulation and measurement results indicate that the proposed technique can achieve a wideband impedance bandwidth and a sufficient AR bandwidth. Furthermore, the proposed CP antenna provides a less directive radiation pattern compared to a linearly-polarized antenna, which can be attractive in receiving performance. [ABSTRACT FROM AUTHOR]

Celestite modification could greatly improve the activity and stability of g-C 3 N 4 for the photocatalytic NO removal. In our system, celestite particles embed in the N vacancies of g-C 3 N 4. The synergistic effect of celestite and N vacancy is the origin of improved NO removal activity. During the light irradiation, photogenerated electrons can be captured and confined by N vacancy. Meanwhile, celestite can transfer these confined electrons to O 2 and produce more OH, which could oxidize NO to nitrate. • Celestine modification could greatly improve the activity and stability of g-C 3 N 4 for the photocatalytic NO removal. • Celestite particles embed on the surface of g-C 3 N 4. • Celestine can facilitate the generation of OH via a Fenton like reaction. • The synergistic effect of celestite and N vacancy is the origin of improved NO removal activity. Atmospheric NO is one of the toxic and hazardous gases. Its' levels are continually rising in recent years. As we known, mineral particles contained in the atmosphere may affect the photocatalytic NO removal process. In this study, we found that celestite modification could greatly improve the activity (about 3.8 times) and stability of g-C 3 N 4 for the photocatalytic NO removal. In our system, celestite particles embed in the N vacancies of g-C 3 N 4. The synergistic effect of celestite and N vacancy is the origin of improved NO removal activity. During the light irradiation, photogenerated electrons can be captured and confined by N vacancy. Meanwhile, celestite can transfer these confined electrons to O 2 and produce more ·OH, which could oxidize NO to nitrate. These findings can help us to understand the influence of mineral particles in the photocatalytic NO removal and design highly efficient NO removal phtocatalysts. [ABSTRACT FROM AUTHOR]

[Display omitted] • TiO 2 /FeS 2 shows 95.7% and 92.4% sterilization against E. coli and S. aureus. • S-O bonds between TiO 2 and FeS 2 could improve the light absorption and reduce the carrier recombination. • Under light, FeS 2 photosensitized TiO 2 produced ROS, which effectively killed bacteria. • TiO 2 /FeS 2 coated the bacterial surface in the dark and significantly reduced its activity. Driven by market demand and resourcefulness of low-value minerals, the preparation of low-cost visible photocatalytic bactericidal materials has become a research hotspot. Here, a simple solvothermal method was constructed FeS 2 photosensitized TiO 2 , which is a promising antibacterial and photocatalytic sterilization strategy. The disinfection efficiency of TiO 2 /FeS 2 for Escherichia coli (E. coli) and Staphylococcus aureus (S. aureus) was 95.7 and 92.4%, respectively. In the darkness, TiO 2 /FeS 2 could wrap around the surface of bacterial cells and significantly decrease their metabolic activity of bacterial cells of E. coli and S. aureus to 21.4% and 30.1%, respectively. Under the light irradiation, TiO 2 /FeS 2 exhibited the light absorption feature of both TiO 2 and FeS 2. Meanwhile, an internal electric field from FeS 2 to TiO 2 was established to realize electron transmission, which as dominant role cooperating with the surface redox reaction, allowed TiO 2 /FeS 2 produced obviously higher •OH, •O 2 –, and 1O 2 to perform an ideal disinfection effect. [ABSTRACT FROM AUTHOR]

In this study, SrTiO 3 catalyst decorated with SrCO 3 was prepared by one step in-situ pyrolysis and was used for the photocatalytic removal of NO. The presence of SrCO 3 not only improved the photocatalytic activity of SrTiO 3 but also inhibited the deactivation of SrTiO 3 during NO removal. In photocatalytic process, the photogenerated electrons in CB of SrTiO 3 could migrate to the CB of SrCO 3 . Meanwhile, strong O 2 adsorption on the SrCO 3 surface would increase the production of O 2 − . Moreover, SrCO 3 could increase the surface acidity of SrTiO 3 , which would increase the NO adsorption and facilitate the oxidation of NO. The experimental data suggested that SrCO 3 functions as surface deposited noble metals without the shortcomings caused by noble metals. Overall, the prepared SrCO 3 looks promising as environmentally friendly and economic substitute to noble metals. [ABSTRACT FROM AUTHOR]

In this study, we synthesized Cu 2 O particles with rough surfaces by a facile solvothermal method as a dual-function material that can degrade contaminants not only under light irradiation but also in dark circumstance. Both the as-prepared Cu 2 O and commercial Cu 2 O exhibited excellent performance for the removal of methyl orange under visible light irradiation through a photocatalysis-based strategy. However, the former was found to show remarkable capability under dark circumstances by means of molecular oxygen activation, while the latter performed poor efficiently under the same condition. This significant difference of performances under dark circumstances was related to rich oxygen vacancies existed on the as-prepared Cu 2 O surfaces that are associated with the single-electron reduction of O 2 to generate O 2 − , which play a dominant role in the generation of Cu + . In addition, Cu + was identified to play key roles in the broken of azo bond. Then, the generated intermediates were mineralized by OH generated through molecular oxygen activation process. This study could not only deep the understanding of the MO removal mechanism by Cu 2 O but also show a novel direction of amphibious application for photocatalytic materials. [ABSTRACT FROM AUTHOR]

Photocatalytic oxidation has recently been recognized as an attractive technology for NO removal, in which the main products are NO 2 or HNO 3 . However, these products may cause secondary pollution and deactivation of the involved photocatalysts. In this study, we demonstrate that carbon vacancy-modified nanosheet structure g-C 3 N 4 (Ns-g-C 3 N 4 ) can efficiently and selectively reduce NO to N 2 under visible light. Since N 2 is a green gas and can easily desorb from the active sites, the problems such as secondary pollution and catalyst deactivation are largely avoided. It was found that two structural characters of Ns-g-C 3 N 4 , ultrathin nanostructure and abundant surface defect sites, could promote its visible light absorption, and favor the separation and transfer of photogenerated charge carriers as well as strong chemisorption of NO, leading to high photoreactivity. Meanwhile, the surface defects of Ns-g-C 3 N 4 shift the adsorption structure of NO from C N O for the bulk counterpart to Cv O N (adsorbed at the carbon vacancy site, Cv), eventually resulting in its high selectivity of converting NO to N 2 . The present study underlines the impetus of utilizing surface defect structure to regulate photocatalytic reaction pathway. [ABSTRACT FROM AUTHOR]

The utilization of photocatalytic technology to remove air pollutants has attracted global interest. However, it still suffers from low removal activities under visible light irradiation. In this study, we demonstrated that the switching of the semiconducting behavior from n -type to p -type can efficiently improve the photocatalytic activity of g-C 3 N 4 for nitric oxide (NO) removal about 3.5 times. This is due to that such switching could change the majority of carriers in g-C 3 N 4 from electrons to holes. Interestingly, the photocatalytic removal of NO in both n -type and p -type g-C 3 N 4 is proceeded via hole oxidation. More importantly, p -type g-C 3 N 4 displays strong stability in both photocatalytic performance and crystal structures. This study provides a new strategy to improve the photocatalytic activity of semiconductors for air pollution removal. [ABSTRACT FROM AUTHOR]

Design of 2-Dimensional nanostructured photocatalyst is an effective way to improve the photocatalytic activity of its bulk counterpart. However, the remaining (or newborn) drawbacks, such as enlarged band gap and the surface recombination of photogenerated charge carries, extremely limited the practical application of nanosheeted photocatalysts in solar energy conversion. In this study, we demonstrated that the voids padding with NH 4 Cl can eliminate part of quantum size effect to reduce the band gap of nanosheeted carbon nitride. In addition, the padded NH 4 Cl can create conjugate center and interface electric field in nanosheeted carbon nitride, and therefore to inhibit the surface recombination of photogenerated charge carries. This work not only provides a facile strategy to eliminate the drawbacks of nanosheeted carbon nitride, but also paves a new way to further improve the photocatalytic activity of other nano-sheeted materials. [ABSTRACT FROM AUTHOR]

Hydrogen peroxide is a promising solar fuel and widely used in many industrial processes. Here we report on a new basis for clean energy storage, generating H 2 O 2 from H 2 O and O 2 by organic photocatalysis. In this study, we construct an all-solid-state Z-scheme heterojunction (PI x -NCN) by assembling perylene imides (PI) on g-C 3 N 4 nanosheets (NCN), where x is a percentage weight ratio of PI to NCN. PI x -NCN exhibits significant enhancement in photocatalytic production H 2 O 2 , and the maximum enhancement was observed for PI 5.0 -NCN. It was shown that PI can change H 2 O 2 generation from single-channel to two-channel. Specifically, photoexcitation of the PI moieties transfers their conduction band electrons to the valence band of NCN, resulting in enhanced charge separation. Thus, more electrons are available to reduce O 2 , producing more H 2 O 2 . More importantly, the holes in the valence band of PI moiety have more positive potential (2.08 V) than those of NCN (1.63 V), which can oxidize OH − to form OH (1.99 V) and transform to H 2 O 2 via the second channel. Therefore, for PI x -NCN, the photogenerated electrons and holes can be separated into two different phases, helping spatially isolate the oxidation and reduction reaction sites, and thus minimizing the catalytic deactivation. [ABSTRACT FROM AUTHOR]

Hydrogen peroxide (H 2 O 2 ) is of great significance in biological and environmental processes as well as in chemical industry. Even though anthraquinone autoxidation (AO) process has been the major artificial way to produce H 2 O 2 , its energy cost and non-green nature have been motivating people to develop more efficient, economic and green technologies as alternatives. Here we demonstrated that photocatalytic H 2 O 2 production at g-C 3 N 4 could be improved by as much as 14 times in the absence of organic scavenger through a carbon vacancy-based strategy. Both the experimental and theoretical calculation results indicated that the creation of carbon vacancies could reduce the symmetry of g-C 3 N 4 and produce the effect of electron delocalization. This will allow g-C 3 N 4 to possess more excitable electrons and a narrower band gap. On the other hand, carbon vacancies provided more sites to adsorb molecular oxygen and thereby help electrons transfer from g-C 3 N 4 to the surface adsorbed O 2 . More interestingly, the presence of carbon vacancies changed the H 2 O 2 generation pathway from a two-step single-electron indirect reduction to an one-step two-electron direct reduction. This study could not only develop a novel strategy to improve the H 2 O 2 production activity of semiconductors, but also shed light on the deep understanding of the role played by surface defect structure on photocatalytic activity of semiconductor photocatalysts. [ABSTRACT FROM AUTHOR]

We reported the possible synthesis of a new porous graphene-like carbon nitride (C 6 N 9 H 3 ) by simply adding hydrochloric acid in the precursor of block g-C 3 N 4 . The formation of the porous graphene-like C 6 N 9 H 3 can be attributed to the change in the thermal condensation modal of the precursor and the acidic condition induced by Cl − and H + . The photocatalytic activity of the samples was evaluated by the removal of NO under visible light illumination. We found that the porous graphene-like C 6 N 9 H 3 exhibited enhanced photocatalytic activity compared to the block g-C 3 N 4 . We also researched the removal mechanism and found that the removal of NO in our systems was due to the synergic effect of h + and O 2 − . This study could shed light on the design of efficient photocatalysts and facilitate a deep understanding of the NO removal mechanism through photocatalytic technology. [ABSTRACT FROM AUTHOR]

Numerous publications have investigated nitric oxide (NO) removal through semiconductor photocatalytic technology. However, few reports are available on the products and mechanisms of the photocatalytic NO removal process. In this study, BiOI hollow microspheres are synthesized for the photocatalytic removal of NO under the visible light irradiation. Results show that NO removal product and NO removal mechanism could interfere with each other. NO removal process could be changed from nonselective oxidation to selective oxidation as the irradiation time increases. Meanwhile, the product of NO removal could be changed from nitrate (NO 3 − ) to nitrogen dioxide (NO 2 ). These interesting changes were attributed to the generated NO 3 − , which was produced from the reactions between NO and OH. The generated NO 3 − could inhibit OH generation, thus leading to a change in the NO removal products and NO removal mechanism. This study can improve our understanding of NO removal on the photocatalyst surface and serve as a guide in using photocatalysts for NO removal. [ABSTRACT FROM AUTHOR]

In this study, nanoscale zero-valent copper (nZVC) was synthesized with a facile solvothermal method and used for the aerobic removal of azo contaminants at neutral pH for the first time. We found that both Cu(I) and OH generated during the nZVC induced molecular oxygen activation process accounted for the rapid total destruction of azo contaminants in the nZVC/Air system, where nZVC could activate molecular oxygen to produce H 2 O 2 , and also release Cu(I) to break the –N N– bond of azo contaminants via the sandmeyer reaction for the generation of carbon center radicals. The in-situ generated carbon center radicals would then react with OH produced by the Cu(I) catalyzed decomposition of H 2 O 2 , resulting in the generation of low molecular weight organic acids and their subsequent mineralization. The indispensible role of Cu(I) catalyzed sandmeyer reaction and the promotion effect of in-situ generated carbon center radicals on the rapid total destruction of azo contaminants in the nZVC/Air system were confirmed by gas chromatography–mass spectrometry analysis. This study can deepen our understanding on the degradation of organic pollutant with molecular oxygen activated by zero valent metal, and also provide a new method to remove azo contaminants at neutral pH. [ABSTRACT FROM AUTHOR]

Artificial photoreduction of CO 2 to clean energy utilizing the unlimited solar energy has shown promise to suppress the greenhouse effect and alleviate the energy shortage. In this study, a simple one-step calcination method was utilized to synthesize ultrathin nanosheet g-C 3 N 4 (NS-g-C 3 N 4). The prepared NS-g-C 3 N 4 with a thickness of 10 nm was demonstrated to exhibited higher efficiency and selectivity than that of bulk counterpart (B-g-C 3 N 4) for the photocatalytic reduction of CO 2 to CO under visible light irradiation. The yield of CO in the system with obtained NS-g-C 3 N 4 was 5.8 times higher than that of B-g-C 3 N 4. CO was measured to be the sole product detected in the system with NS-g-C 3 N 4 , while CO 2 can be reduced into CO, CH 4 and CH 3 OH in the system with B-g-C 3 N 4 under the same photocatalytic reduction conditions. The ultrathin nanostructures and abundant surface defect sites of NS-g-C 3 N 4 could enhance the visible light adsorption efficiency, favor the separation and transfer of photogenerated carriers, and provide strong chemisorption sites for CO 2 , and thus resulting in its remarkable photocatalytic activity to CO 2 reduction. More importantly, the surface defects of nanosheet could shift the adsorption mode of CO 2 from N–CO 2 - for the B-g-C 3 N 4 to N–O–C O for NS-g-C 3 N 4 , and eventually contributing the selective photoreduction of CO 2 to CO. The obtained also NS-g-C 3 N 4 exhibited excellent stability for CO 2 photoreduction. No significant change in the photoreduction efficiency of CO 2 in the system with NS-g-C 3 N 4 was observed after four cycles. This study could not only provide a novel strategy to realize the high selectivity and efficiency photocatalytic conversion CO 2 to CO, but also aims to clarify the interactions between the adsorption model of CO 2 on g-C 3 N 4 surface and the selectivity and efficiency of CO 2 photoreduction. [Display omitted] • Shelled g-C 3 N 4 structure from bulk to ultrathin nanosheet could increase its surface defect sites. • NS-g-C 3 N 4 exhibited stronger chemisorption of CO 2 than B-g-C 3 N 4. • NS-g-C 3 N 4 could change the adsorption mechanism of CO 2. • NS-g-C 3 N 4 could selectively photoreduce CO 2 to CO without other by-products. [ABSTRACT FROM AUTHOR]

• Group IIA element ion-doped g-C 3 N 4 samples were successfully synthesized. • Structure distortion could suppress the recombination of surface charge carriers. • Group IIA element ion could serve as interlayer electron channels. • The structural distortions could create more chemisorption sites of O 2. In this study, Group IIA element ion-doped g-C 3 N 4 samples were synthesized to eliminate above two disadvantages and increase photocatalytic NO removal activity. The experimental results showed that the Group IIA element ions could form coordination bonds with the nitrogen atoms in the triazine rings of g-C 3 N 4 that distorted the g-C 3 N 4 structure because of uneven force. The structure distortion destroyed the surface electronic delocalization and suppressed the recombination of surface charge carriers. Additionally, the formed coordinate bonds connected two adjacent layers and served as interlayer electron channels, which could significantly improve the electron transport between two layers. Additionally, structural distortions created more amino and imino groups, which are the chemisorption sites of O 2. Therefore, the modified g-C 3 N 4 samples produced more reactive oxygen species to remove NO. The degree of distortion and the NO removal activity increased as the Group IIA atomic number increased. [ABSTRACT FROM AUTHOR]

g-C 3 N 4 was modified by multi-site Sr-doping with simultaneous N atoms replacement, cavity padding, and intercalation. The effects of doped Sr were different with different doping position. The Sr that intercalated in the interlayer of g-C 3 N 4 could improve the transfer of photogenerated electrons by forming a charge channel between two crystal planes, the Sr that replaced the N atoms could help the activation of O 2 to produce more O 2 −, and the Sr padded in the cavity provides g-C 3 N 4 with the ability to activate the H 2 O 2 for the generation of a stronger oxidant (OH), which could deeply oxidize NO to NO 3 −. The different doping modes complement each other and combine to realize efficient and deep NO removal. • Multi-site Sr-doped g-C 3 N 4 with simultaneous N atoms replacement, cavity padding, and intercalation. • Multi-site doping of Sr decreased the conversion rate of secondary pollution (NO 2) from 62.5% to 15.8%. • The effects of doped Sr were different with different doping modes. • The different doping modes complement each other and combine to realize efficient and deep NO removal. The NO removal activity of g-C 3 N 4 is limited by many shortcomings including the high recombination rate of photo-generated carriers and secondary pollution induced by incomplete oxidation. Here, we modified g-C 3 N 4 using multi-site Sr-doping with simultaneous N atoms replacement, cavity padding, and intercalation. The NO removal experiments showed that multi-site doping of Sr improved the NO removal rate by 1.5 times. Meanwhile, the conversion rate of secondary pollution (NO 2) decreased from 62.5% to 15.8%. The effects of doped Sr were different with different doping modes. All the doping modals of Sr could decrease the band gap of g-C 3 N 4. Meanwhile, the Sr that intercalated in the interlayer of g-C 3 N 4 could improve the transfer of photogenerated electrons; the Sr that replaced the N atoms could help the activation of O 2 to produce more O 2 −; the Sr padded in the cavity provides g-C 3 N 4 with the ability to activate the H 2 O 2 for the generation of a stronger oxidant (OH). The different doping modes complement each other and combine to realize efficient and deep NO removal. [ABSTRACT FROM AUTHOR]

At present, there are many kinds of pollutants, including dyes and heavy metal ions, in wastewater. It is very important to develop adsorbents that can simultaneously remove heavy metal ions and dyes. In this study, a renewable composite membrane material was synthesized using chitosan and treated coal gasification slag. The Cr (VI) maximum adsorption capacity of the composite membrane was 50.0 mg/L, which was 4.3~8.8% higher than that of the chitosan membrane. For the adsorption of RhB, the removal rate of the chitosan membrane was only approximately 5.0%, but this value could be improved to 95.3% by introducing coal gasification slag. The specific surface area of the chitosan membrane could also be increased 16.2 times by the introduction of coal gasification slag. This is because coal gasification slag could open the nanopores of the chitosan membrane (from 80 μm to 110 μm). Based on the adsorption kinetics and adsorption mechanism analysis, it was found that the adsorption of Cr (VI) occurred mainly through the formation of coordination bonds with the amino groups on the molecular chains of chitosan. Meanwhile, RhB adsorption occurred through the formation of hydrogen bonds with the surface of coal gasification slag. Additionally, coal gasification slag can improve the mechanical properties of the chitosan membrane by 2.2 times, which may facilitate the practical application of the composite membrane. This study provides new insight into the adsorbent design and the resource utilization of coal gasification slag. [ABSTRACT FROM AUTHOR]

Photocatalysis technology is used to remove the low concentration NO in recent years. However, the effect of this process is not very satisfactory. In this study, it was found that the prepositive NaOH solution could significantly improve the photocatalytic NO removal activity of g-C 3 N 4. The apparent quantum yield of g-C 3 N 4 in the NO removal process was increased 3.5 times by the prepositive NaOH solution. The reason is that there was a synergistic effect formed between the prepositive NaOH solution and the photocatalytic NO removal process. The prepositive NaOH solution not only could increase the humidity and pH value in the photocatalytic unit, but also could improve the adsorption ability of g-C 3 N 4 for the H 2 O, NO, and O 2. Moreover, the prepositive NaOH solution reduced the difficulty of the photogenerated carriers' transport and the ·OH generation. This study provided a new idea for the removal of low-concentration NOx. [ABSTRACT FROM AUTHOR]

Graphical abstract Highlights • NCN/PI/rGO and NCN/rGO/PI variations were synthesised through different reaction sequences. • The different introduction order of rGO produces different photocatalytic redox performances. • NCN/PI/rGO exhibited superior photocatalytic NO removal and generation of H 2 O 2 in visible light. • The simultaneous electron transfer (PI→NCN→rGO) cause higher carrier separation efficiency. • However, the rGO in the NCN/rGO/PI only acts as an electron transport bridge. Abstract g-C 3 N 4 -based photocatalysts are recognized as promising candidates for photocatalytic purification of air and solar energy conversions; but their practical application is still limited by the sluggish charge transfer dynamic. Herein, a Z-scheme ternary heterojunction (nanosheet–g-C 3 N 4 [NCN]/perylene imide [PI]/reduced graphene oxide [rGO], NCN/PI/rGO) was successfully constructed. For experimental comparison, NCN/rGO/PI was concurrently synthesized through different reaction sequences. In these ternary heterojunction systems, the introduction order of rGO affects the morphology structure and the interaction between phases and results in two diverse electron transfer modes which determine the different photocatalytic redox performances. The as-obtained NCN/PI/rGO Z-scheme heterostructure exhibited superior photocatalytic activity towards the photocatalytic removal of NO and generation of H 2 O 2 under visible light irradiation. Such photocatalytic activity was about 1.58 and 1.23 times higher than those of NCN and NCN/PI, respectively, in NO removal. Such enhanced photocatalytic properties can be ascribed to the two-step electron transfer process involving the CB electrons in PI combined with the VB holes of NCN via the Z-scheme pathway (process I, PI→NCN) because PI was grown in situ on the NCN through thermal condensation polymerisation. This process enabled intimate contact between NCN and PI and a short charge-transfer distance. The residual electrons in the CB of NCN then flowed into the rGO (process II, PI→NCN→rGO). Thus, the simultaneous occurrence of two electron transfers processes I and II help improve the photocatalytic activity. Constructing NCN/PI/rGO Z-scheme heterostructures is anticipated to be an effective strategy for developing high-performance photocatalysts that facilitate the utilisation of solar energy. [ABSTRACT FROM AUTHOR]

Two‐dimensional (2D) photocatalysts are highly attractive for their great potential in environmental remediation and energy conversion. Herein, we report a novel layered zinc silicate (LZS) photocatalyst synthesized by a liquid‐phase epitaxial growth route using silica derived from vermiculite, a layered silicate clay mineral, as both the lattice‐matched substrate and Si source. The epitaxial growth of LZS is limited in the 2D directions, thus generating the vermiculite‐type crystal structure and ultrathin nanosheet morphology with thicknesses of 8–15 nm and a lateral size of about 200 nm. Experimental observations and DFT calculations indicated that LZS has a superior band alignment for the degradation of organic pollutants and reduction of CO2 to CO. The material exhibited efficient photocatalytic performance for 4‐chlorophenol (4‐CP) degradation and CO2 conversion into CO and is the first example of a claylike 2D photocatalyst with strong photooxidation and photoreduction capabilities. [ABSTRACT FROM AUTHOR]

Two‐dimensional (2D) photocatalysts are highly attractive for their great potential in environmental remediation and energy conversion. Herein, we report a novel layered zinc silicate (LZS) photocatalyst synthesized by a liquid‐phase epitaxial growth route using silica derived from vermiculite, a layered silicate clay mineral, as both the lattice‐matched substrate and Si source. The epitaxial growth of LZS is limited in the 2D directions, thus generating the vermiculite‐type crystal structure and ultrathin nanosheet morphology with thicknesses of 8–15 nm and a lateral size of about 200 nm. Experimental observations and DFT calculations indicated that LZS has a superior band alignment for the degradation of organic pollutants and reduction of CO2 to CO. The material exhibited efficient photocatalytic performance for 4‐chlorophenol (4‐CP) degradation and CO2 conversion into CO and is the first example of a claylike 2D photocatalyst with strong photooxidation and photoreduction capabilities. [ABSTRACT FROM AUTHOR]

Abstract In this work, a new activated carbon fiber (ACF) cathode modified with graphitic carbon nitride (g-C 3 N 4) was developed, which enables the substantially improved production of H 2 O 2 (up to 32.8 mg L−1) with relatively low energy consumption (10.9 kWh kg−1) compared to generation without g-C 3 N 4 (4.09 mg L−1). The cathode was analyzed and characterized by scanning electron microscopy, X-ray photoelectron spectroscopy and X-ray diffraction, and it was proved that the synthesized g-C 3 N 4 is a thin layer sheet with a large number of carbon particles and low defect porosity. The cathode manufacturing parameters were optimized, and the influences of H 2 O 2 production including the cathode potential, pH value, aeration rate and performance stability were studied. These features improved the production of H 2 O 2 by about more than 7 folds when optimized ratio of g-C 3 N 4 was used, and the modified cathode kept stable performance of H 2 O 2 generation in 5 cycles. Further discussed by linear sweep voltammetry, rotating disk electrode and contact angle analysis, the existence of g-C 3 N 4 were found to accelerate the electron transfer rate, is advantageous to the surface of the oxygen reaction, but will not change the two electronic number of oxygen reduction reaction activities, and this leads to enhanced performance of hydrogen peroxide production and the possible mechanism was suggested. Finally, the cathode improve by g-C 3 N 4 proved the degradation effect of phenol by photoelectric-Fenton process. Phenol was degraded completely, and 93.8% of the organic carbon was removed, which is more than 1.5 and 5 times the amount achieved using electro-Fenton and photo-Fenton degradation only. In the degradation process of phenol, electrocatalysis and photocatalysis, they were optimized to produce substantial synergistic effect, proving the great potential practical application of organic wastewater treatment. Highlights • g-C 3 N 4 /ACF electrode exhibit good photoelectrochemical properties under. • The functionalize carbon electrode can effectively generate H 2 O 2. • During the degradation process of phenol, electro- and photocatalysis support and optimize each other. [ABSTRACT FROM AUTHOR]

The SrBi 2 Nb 2 O 9 platelets with a thickness of about 600 nm were synthesized by molten salt synthesis method. The treatment of the SrBi 2 Nb 2 O 9 platelets with hydrochloric acid resulted in the formation of the protonated H 1.78 Sr 0.78 Bi 0.22 Nb 2 O 7 platelets. Through a top–down approach in ethylamine solution, the H 1.78 Sr 0.78 Bi 0.22 Nb 2 O 7 platelets were exfoliated into H 1.78 Sr 0.78 Bi 0.22 Nb 2 O 7 nanosheets with a thickness of about 2.6 nm. The evolution of the structure, composition, morphology, optical, and photocatalytic properties of SrBi 2 Nb 2 O 9 platelets was studied as it is converted into H 1.78 Sr 0.78 Bi 0.22 Nb 2 O 7 platelets and subsequently exfoliated into H 1.78 Sr 0.78 Bi 0.22 Nb 2 O 7 nanosheets. The absorption edge shifts to a lower wavelength accompanied by the protonation and exfoliation. The photocatalytic H 2 evolution of the three samples were evaluated under the irradiation of a 300 W Xenon lamp from CH 3 OH/H 2 O solution, indicating that H 1.78 Sr 0.78 Bi 0.22 Nb 2 O 7 nanosheets Exhibit 5.5 and 26.2 times higher activity than that of the H 1.78 Sr 0.78 Bi 0.22 Nb 2 O 7 and SrBi 2 Nb 2 O 9 platelets, respectively. The enhanced activity for the H 1.78 Sr 0.78 Bi 0.22 Nb 2 O 7 nanosheets is mainly attributed to the higher separation efficiency of the photogenerated carriers and the larger specific surface area caused by the significant reduction in thickness. [ABSTRACT FROM AUTHOR]

Electrical conductivity relaxation (ECR) technique has been widely used to determine kinetic properties of mixed ionic and electronic conductors (MIECs). However, this technique is only applicable for reliable determination of kinetic parameters within a confined range of chemical Biot numbers. Since the kinetic properties of the materials are not known a priori, this imposes great difficulties on how to verify the obtained kinetic parameters from obtained ECR data. Further due to the ill-posed nature of ECR problem, the measurement noise could lead to significant uncertainties in the determined kinetic parameters. Herein a generalized ECR (g-ECR) approach is developed by coherently incorporating multiple ECR measurements simultaneously into an inverse algorithm. This new approach is able to improve the accuracy of calculated kinetic parameters and attenuate uncertainties induced by measurement noise over a wider range of chemical Biot numbers than the ECR approach with a single measurement. The capability of both reducing uncertainties and increasing the range of chemical Biot numbers for accurate parameter determination can be achieved by increasing the number of employed ECR measurement responses. A case study of ECR measurement for PrBa(Co 0.75 Fe 0.25 ) 2 O 5 + δ is performed in a mixture gas of N 2 /Air at 600 °C. The kinetic parameters are determined and evaluated using this g-ECR approach. The rationality of using g-ECR approach instead of ECR approach is verified. [ABSTRACT FROM AUTHOR]

Benefiting from the Br− selectively induced the OVs on {001} facets of Bi 2 MoO 6 , an extended light-absorption until near-infrared region and enhanced the molecular oxygen activation were achieved, thus endowing the OVs concentration optimized Bi 2 MoO 6 with superior activity and selectivity of NO removal in a flow reaction. • Br− boost the construction and stabilization of OVs on {001} facets of Bi 2 MoO 6. • Br− induced OVs facilitate NO removal of BMO-001-Br even in near-infrared region. • NO oxidative removal with high selectivity of 93.6% is achieved on BMO-001-Br. • Mechanism for highly efficient NO removal (62.9%) over BMO-001-Br is proposed. Surface oxygen vacancies (OVs) are believed as active sites for photocatalytic NO removal. The construction and stabilization of OVs on materials, especially from the point of view of exogenous ions towards different facets is vital for OVs-mediated photocatalysis. Herein, the impact of bromide ions (Br−) on OVs construction on different facets of Bi 2 MoO 6 was systematically investigated. Theoretical calculations and characterizations demonstrated that Br− can boost and stabilize the OVs on {001} facets of Bi 2 MoO 6 , while hardly affect that on {010} facets. The Br- induced OVs on Bi 2 MoO 6 caused a light-absorption until near-infrared region and enhanced the molecular oxygen activation, thus endowing the OVs concentration optimized Bi 2 MoO 6 (BMO-001-Br) with superior activity on NO removal (62.9%) and selectivity of NO complete oxidation (93.61%) in a flow reaction. This work provides new insight into understanding the exogenous ions on construction and stabilization of OVs and the roles of OVs in photocatalytic NO removal. [ABSTRACT FROM AUTHOR]