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A zirconium-based metal-organic framework containing boron (UiO-66-B) is prepared, which displays efficient photocatalytic H

This study aimed to explore the value of dynamic magnetic resonance imaging (MRI) before and after operation for pelvic organ prolapse (POP).Twenty-nine patients with POP (POP group) before and one month after surgery and 12 healthy women (control group) underwent static and dynamic MRI at rest and during straining (Valsalva maneuver). The preoperative MRI images of the POP and control groups were analyzed, and various measurements were recorded. Differences in measurements were compared between the POP and control groups; similarly, changes in measurements before and after operation were compared.In the POP group, MRI detected 29 anterior vaginal prolapses, 27 uterine prolapses, 1 rectoceles, and 14 pouch of Douglas hernias. In addition, 27 levator ani muscle defect and 15 pubocervical fascial defect cases were observed. The bladder-pubococcygeal line (B-PCL), uterus-pubococcygeal line (U-PCL), Douglas pouch-pubococcygeal line, the length of the hiatus, the descent of the levator plate, levator hiatus size, levator plate angle, iliococcygeus angle, and urethral inclination angle (UA) were larger in the POP group than in the control group. The pelvic organs' positions returned to normal postoperatively in 9 of 21 cases. The B-PCL, U-PCL, and UA were smaller post-surgery than pre-surgery.Static and dynamic MRI can comprehensively evaluate morphological and functional changes of the pelvic floor postoperatively.

ZnO, as an important semiconductor material, has attracted much attention due to its excellent physical properties, which can be widely used in many fields. Notably, the defects concentration and type greatly affect the intrinsic properties of ZnO. Thus, controllable adjustment of ZnO defects is particularly important for studying its photoelectric properties. In this work, we fabricated ZnO ceramics (ZnO(C)) with different defects through spark plasma sintering (SPS) process by varying sintering temperature and using reduction environment. The experimental results indicate that the changes of color and light absorption in as-prepared ZnO originate from the different kinds of defects, i.e., oxygen vacancies (VO), interstitial zinc (Zni), and Zinc vacancies (VZn). Moreover, with the increase in calcination temperature, the concentration of oxygen defects and interstitial zinc defects in the ceramics increases gradually, and the conductivity of the ceramics is also improved. However, too many defects are harmful to the photoelectrochemical properties of the ceramics, and the appropriate oxygen defects can improve the utilization of visible light.

Monoclinic bismuth vanadate (BiVO4) is an attractive material with which to fabricate photoanodes due to its suitable band structure and excellent photoelectrochemical (PEC) performance. However, the poor PEC stability originating from its severe photo-corrosion greatly restricts its practical applications. In this paper, pristine and Mo doped BiVO4 ceramics were prepared using the spark plasma sintering (SPS) method, and their photoelectrochemical properties as photoanodes were investigated. The as-prepared 1% Mo doped BiVO4 ceramic (Mo-BVO (C)) photoanode exhibited enhanced PEC stability compared to 1% Mo doped BiVO4 films on fluorine doped Tin Oxide (FTO) coated glass substrates (Mo-BVO). Mo-BVO (C) exhibited a photocurrent density of 0.54 mA/cm2 and remained stable for 10 h at 1.23 V vs. reversible hydrogen electrode (RHE), while the photocurrent density of the Mo-BVO decreased from 0.66 mA/cm2 to 0.11 mA/cm2 at 1.23 V vs. RHE in 4 h. The experimental results indicated that the enhanced PEC stability of the Mo-BVO (C) could be attributed to its higher crystallinity, which could effectively inhibit the dissociation of vanadium in BiVO4 during the PEC process. This work may illustrate a novel ceramic design for the improvement of the stability of BiVO4 photoanodes, and might provide a general strategy for the improvement of the PEC stability of metal oxide photoanodes.

Black liquor, an industrial waste product of papermaking, is primarily used as a low-grade combustible energy source. Despite its high lignin content, the potential utility of black liquor as a feedstock in products manufacturing, remains to be exploited. Demonstrated here in is the use of black liquor as a primary feed-stock for synthesizing graphene quantum dots that exhibit both up-conversion and photoluminescence when excited using visible/near-infrared radiation, thereby enabling the photosensitization of ultraviolet-absorbing TiO2 nanosheets. In addition, these graphene quantum dots can trap photo-generated electrons to realize the effective separation of electron-hole pairs. Together, these two processes facilitate the solar-powered generation of H2 from H2 O, and CO from H2 O-CO2 , using broadband solar radiation.

In this work, we employed Yb3+ and Er3+ ions doped in a narrow bandgap oxide Bi20TiO32 to fabricate Bi20TiO32:Yb,Er, which can achieve near-infrared (NIR) responsive upconversion (UC) photocatalysi...

The synthetic CaO/Ca12Al14O33 sorbent has been regarded as an efficient CO2 sorbent during the calcium looping cycles. In this work, the CO2 adsorption performance of the synthetic CaO/Ca12Al14O33 sorbent in the presence of H2O was investigated by density functional theory (DFT) calculations. DFT was used to analyze the adsorption of CO2 and H2O on the synthetic sorbent. Both structural parameters (atomic layout and electronic configuration) and the adsorption parameters (energy, bond lengths, angles, bond population and charge transfer) of CO2 and H2O on the synthetic sorbent were determined. To confirm the feasibility of DFT analysis, the CO2 capture performance of the synthetic sorbent in the presence of steam was examined in a dual fixed bed reactor. The results indicate strong interactions between the C atom and the O atom in CaO and interactions between the H atom and the O atom in CaO. The higher adsorption energy of CO2 than H2O on pristine CaO and Ca12Al14O33-supported CaO suggests that the adsorptions of CO2 and H2O are competitive and that the adsorption of CO2 is stronger than that of H2O. The adsorption of H2O leads to the activation of adjacent O atoms of CaO and thus stronger CO2 adsorption on the O atom with H2O adsorbed. The electrons in the p orbital of the O atom near the Fermi level play important roles in CO2 adsorption by CaO. The presence of Ca12Al14O33 hinders CO2 adsorption by CaO. A low Ca12Al14O33 content in synthetic sorbents should be maintained to ensure high CO2 capture capacity and sintering resistance of synthetic sorbents. DFT calculations can predict the CO2 adsorption performance of CaO-based sorbents with additives under different reaction atmospheres.

Tetragonal zircon BiVO4 (P-BiVO4) were grown on fluorine-doped tin oxide (FTO) glass via hydrothermal method. The cathodic photocurrent and Mott-Schottky analysis indicate that the tetragonal zircon BiVO4 is a p-type semiconductor. Inductively coupled plasma (ICP) analysis and X-ray photoelectron spectrum showed that there are Bi vacancies and interstitial oxygen exist in the crystal, which are the origin of the p-type conductivity. The flat band potential of the P-BiVO4 is about 1.33 V (vs Ag/AgCl) inferred from Mott-Schottky plots. Combining with diffuse reflection spectrum and valence band X-ray photoelectron spectrum, the calculated conduction band value of the P-BiVO4 is about 0.06 V vs RHE, slightly higher than the reduction potential of hydrogen. However, the P-BiVO4 exhibit hydrogen production activity under Xe light irradiation even though its conduction band level is not negative enough. This can be attributed to the hot carrier processes in p-type semiconductors.

In this work, we provide an alternative way to modulate the type of major reactive oxygen species produced during the photocatalytic process. Polar molecular 4-carboxythiophenolate anion (4CBT) mod...

Enhancing the photocatalytic activity of NiO towards hydrogen generation (6 times) is achieved by phenyl phosphoric acid (PPA) surface modification. The photocatalytic activity can be further improved by changing PPA to 4-aminophenyl phosphonic acid (PPA-NH2), about 10 times, suggesting the functional group plays an important role in improving the activity. A chemical bond (Ni O P) between NiO and organic phosphoric acid was proved by FT-IR spectra. XPS and LSV analysis suggested organic phosphonic acid modification increased the electron density of Ni, which promoted the transformation from Ni2+ to Ni0. Mott-Schottky (M − S) measurement revealed that PPA-NH2 modified NiO processed a larger the space charge layer thickness (dsc), which enhanced ability towards H2 evolution from dynamical aspect.

A simple and efficient light-assisted method is employed to prepare powder samples of all-inorganic mixed-perovskite CsPbBr3-xIx from CsPbBr3 by ion exchange in aqueous HBr/KI solution such that the concentration of I in a sample particle decreases on going from the surface to the interior. CsPbBr3-xIx/Pt, namely, CsPbBr3-xIx samples loaded with Pt nanoparticles, shows a high performance for the hydrogen evolution under visible-light irradiation in aqueous HBr solution saturated with CsPbBr3. The H2 evolution rate of the CsPbBr3-xIx/Pt powders (200 mg) is determined to be 224 μmol h−1, under 120 mW cm-2 visible-light (λ ≥ 420 nm) illumination. The CsPbBr3-xIx samples have a high stability, with no apparent decrease in the catalytic activity after 50 h of repeated H2 evolution experiments. The apparent quantum efficiency of CsPbBr3-xIx/Pt is determined to be 2.15% under the irradiation of 450 nm light.

Calcium looping is regarded as an effective and viable way to address CO2 emissions. To overcome the loss-in-capacity problems of calcium-based sorbents with the number of calcium looping cycles, a novel CaO/Ca12Al14O33 sorbent with a microtube-like structure was prepared from carbide slag and Al(NO3)3·9H2O using paper fibre as a biotemplate. The CO2 capture performance and microstructure of the novel synthetic sorbent under calcium looping conditions were investigated. The results show that the utilization of the biotemplate is good to retain the high cyclic CO2 capture reactivity of the synthetic sorbent. Due to the unique hollow porous structure, the CO2 capture capacity of the synthetic sorbent containing 7.5 wt% Al2O3 retains 0.56 and 0.33 g/g after 30 cycles under mild and severe calcination conditions, respectively, which are 2.56 and 2.11 times higher than those of carbide slag under the same respective calcination conditions. With the presence of 10% steam in the carbonation atmosphere, the CO2 capture capacity of the synthetic sorbent retains 0.55 g/g under the severe calcination conditions after 10 cycles. The native hierarchical biostructure of paper fibre is preserved in the synthetic sorbent. CaO and Ca12Al14O33 are uniformly distributed in the synthetic sorbent, resulting in a high sintering resistance during multiple CO2 capture cycles. CO2 can penetrate through the microtube-like structure of the synthetic sorbent from two directions, i.e., from the outer surface and inner surface. This phenomenon effectively enlarges the contact area between CO2 and CaO. The CaO/Ca12Al14O33 sorbent with a hollow porous structure by means of a biotemplate appears promising in the calcium looping technology for CO2 capture.

In this work, we fabricated NaYF4:Yb3+,Tm3+@NaYF4:Yb3+,Nd3+@TiO2 (Tm@Nd@TiO2) core@shell nanoparticles and investigated their near-infrared (NIR) photocatalytic activities. Comparing to traditional TiO2 based upconversion (UC) photocatalysts (i.e., NaYF4:Yb3+,Tm3+@TiO2, named Tm@TiO2), Tm@Nd@TiO2 exhibits enhanced photocatalytic activity under NIR light irradiation. The photocatalytic activity of Tm@Nd@TiO2 under 980, 808, and 980 + 808 nm laser irradiation is 4.40, 5.84, and 9.83 times as high as that of Tm@TiO2 under only 980 nm irradiation, respectively. The ethylene degradation rate of Tm@Nd@TiO2 under 980 + 808 nm laser irradiation is 6.4 times as that of Tm@TiO2. The photocatalytic activity of Tm@Nd@TiO2 under visible + NIR irradiation is even comparable with (∼2/3) that under UV light irradiation during Rhodamine B (RhB) degradation. The enhanced photocatalytic activity of Tm@Nd@TiO2 can be attributed to the stronger light absorption in NIR region ascribed to Nd3+, lower water absorption and the enhanced UC emission of Tm@Nd with unique core@shell nanostructures. This work can provide a possible route to improve the NIR photocatalytic activity and stimulate the applications in many other fields.

Interfacial manipulation of nanostructured heterojunction photocatalysts to enhance charge separation and transfer is highly desirable to achieve a high photocatalytic activity. In this work, a well-designed non-noble-metal Mo2C@C/g-C3N4 heterostructure is constructed, in which the intercalated carbon nanosheets serve as a binder to form an excellent interfacial contact between Mo2C and g-C3N4. In addition, large quantities of carbon quantum dotsare found to be homogeneously embedded in the carbon nanosheets. The as-obtained Mo2C@C/g-C3N4 hybrid exhibits a remarkably improved photocatalytic H2 evolution rate of 52.1 μmol h−1 under visible-light irradiation (λ ≥ 420 nm) without co-catalyst, which is up to nearly 260 times higher than that of pristine g-C3N4 (0.2 μmol h−1) under the same conditions. The significant increase in photocatalytic activity mainly results from the fast charge migration and separation between Mo2C and g-C3N4 facilitated by the conducting carbon nanosheets as an efficient electron mediator. Moreover, the carbon quantum dots embedded in the carbon support also promotes solar energy utilization. This work highlights a feasible strategy to explore highly efficient photocatalysts via interfacial engineering on heterojunction composites.

Layered perovskite oxyhalide Bi4NbO8Cl with exposed (001) lattice plane has been successfully synthesized by Sol–gel method. The obtained products were characterized by X-ray diffraction, diffuse-reflection spectra, scanning electron surface area from Brunauer–Emmitt–Teller analysis. The photocatalytic activity for the decomposition of Rhodamine-B (RhB) aqueous solution can be significantly improved under visible light irradiation. Based on both high charge speration efficiency originated from the large exposed surface areas of (001) facts and high photocatalytic redox ability generated from band gap expansion, sol gel-Bi4NbO8Cl exhibit higher efficiency over solid state-Bi4NbO8Cl during the degradation of organic dyes under visble light irradiation. What’s more, the Sg-Bi4NbO8Cl photocatalyst still kept higher photocatalytic activity after five cycle measurement.

Novel Mn‐doped CaO was prepared by the combustion method. The CO2 capture performance of Mn‐doped CaO, carbonated in the presence of steam and under severe calcination conditions (950°C and 70% CO2/30% N2) during calcium looping cycles, was investigated in a dual fixed‐bed reactor. The intercoupling effects of Mn and steam on CO2 capture by CaO were also studied. Doping of Mn in CaO by the combustion method greatly improved the CO2 capture capacity of CaO. The carbonation conversions of Mn‐doped CaO increased with increasing steam concentration from 0 to 15%. When the molar ratio of Mn/Ca was 0.75 : 100, Mn‐doped CaO achieved the highest CO2 capture capacity. Under severe calcination conditions, the carbonation conversion of Mn‐doped CaO, where the molar ratio of Mn to Ca = 0.75 : 100 in the presence of 15% steam, was about 0.4 after ten cycles (carbonation for 5 min at 650°C under 15% CO2/15% steam/N2), which was 4.38 times as high as that of the original CaO in the absence of steam. The cyclic CO2 capture capacities of CaO were improved by Mn and steam. Synergistic enhancement effects of Mn and steam on the CO2 capture capacities of CaO were also found. The effect of steam on the carbonation conversion of Mn‐doped CaO was stronger than that of the original CaO. Mn in the presence of steam showed a more positive effect on CO2 capture by CaO. X‐ray photoelectron spectroscopy analysis showed that doping of Mn in CaO enhanced the transport of electrons in the carbonation of CaO, which helped to increase the carbonation rate. When steam was present in the carbonation, Mn‐doped CaO possessed a more porous structure and smaller CaO grains than the original CaO during the cycles. Simulation calculations using periodic density functional theory (DFT) showed that CO2 molecules were easier to absorb on CaO owing to the doping of Mn and the presence of steam. The synergistic enhancement effects of Mn and steam on CO2 captured the performance of CaO. © 2019 Society of Chemical Industry and John Wiley & Sons, Ltd.

Photo-electrochemical and electrochemical water splitting are considered as effective ways to realize the efficient hydrogen evolution reaction and solve the increased energy demand. Herein, the photo-responsive MoS2 electrocatalyst modified with Co(OH)2 was synthesized on a carbon cloth (CC) by a facile approach. Benefiting from the heterogeneous interface between MoS2 and Co(OH)2, this hybrid catalyst shows superior HER activity in 1 M KOH aqueous solution with an overpotential of 117 mV at 10 mA cm−2 and a Tafel slope of 59.82 mV dec−1, which are smaller than those of MoS2/CC (an overpotential of 171 mV at 10 mA cm−2 and a Tafel slope of 90.78 mV dec−1) or Co(OH)2/CC (an overpotential of 268 mV at 10 mA cm−2 and a Tafel slope of 99.84 mV dec−1). The HER activity of Co(OH)2/MoS2/CC can be further promoted with an overpotential of 101 mV at 10 mA cm−2 due to the enhanced conductivity and exchange current density under light irradiation. Density functional theory calculations are carried out to gain a deeper insight into the effect of Co(OH)2 MoS2 interface, indicating that the introduction of Co(OH)2 can reduce the energy barrier of the initial water dissociation process and provide the hydroxyl adsorption sites, while MoS2 can promote the adsorption of hydrogen intermediates and H2 release. The synergistic effect of light irradiation and interface engineering strategy can realize efficient hydrogen evolution reaction, which can enlighten and extend to other electrocatalytic system.

A triazine-based MOFs [PCN-9(Co)] was synthesized and its photoelectrical, photophysical properties were studied. As a new photocatalyst, PCN-9(Co) displays photocatalytic hydrogen evolution from water under UV–Visible light irradiation. With the introduction of platinum complex, PCN-9-Pt was obtained and platinum complex was believed to coordinate with the N in triazine. The H2 evolution rate of PCN-9-Pt is greatly improved, about 6.8 times higher than that of PCN-9(Co). The reason is due to the fact that platinum complex plays an important role in improving the separation efficiency of photogenerated charge carriers, as verified by PL and EIS results. This result provides a new kind of idea of modifying MOFs materials with molecular complex to improve the photocatalytic activity.

Photocatalytic hydrogen evolution from water splitting driven by visible light is a promising approach to solve energy crisis and environmental problems, and noble-metal-free co-catalysts for boosting the hydrogen evolution reaction are highly desired. Herein, we explore a novel noble-metal-free Fe2P–Co2P co-catalyst for the first time to boost the photocatalytic performance of graphitic carbon nitride (g-C3N4). The resultant Fe2P–Co2P/g-C3N4 with optimum ratio exhibits a hydrogen production rate of 347 μmol h−1 g−1 in the absence of noble-metal co-catalyst, which is 87 times higher than that of pristine g-C3N4 under the same conditions. The significant enhancement in the photocatalytic performance of Fe2P–Co2P/g-C3N4 can be ascribed to the Schottky junction formed between Fe2P–Co2P and g-C3N4, which produces a strong driving force for the transfer of electrons from g-C3N4 to Fe2P–Co2P, promoting the separation and transfer of photogenerated electrons and holes. Furthermore, due to the synergistic effects between the two metal phosphides (Fe2P and Co2P), the Schottky junction in Fe2P–Co2P/g-C3N4 can produce stronger driving force than that in Fe2P/g-C3N4 and Co2P/g-C3N4, resulting in the fact that the hydrogen production rate over Fe2P–Co2P/g-C3N4 is much higher than that over Fe2P/g-C3N4 and Co2P/g-C3N4. This work may shed light on the careful design of co-catalyst by utilizing the synergistic effect of different components.

In this work, a polar molecule 4-mercaptobenzoic acid (4-MBA) is anchored on the surface of CdWO4 by forming Cd S and W S bond. Photocatalytic hydrogen evolution is significantly enhanced (about 3.41 times) after the modification. The reason is due to the modification of 4-MBA, which results in a polar surface and built-in electric field. The polar surface is confirmed by the steady state and time-resolved PL spectra, Voc and SHG results.

Second-order nonlinear optics (NLO) is the foundation of frequency conversion for the generation of coherent light at frequencies where lasers have no emissions or operate poorly. The prerequisite for NLO materials is noncentrosymmetric symmetry that can generate an effectively non-counterbalanced spontaneous electronic polarization. Here, we propose that this material restriction can be broadened by controlling the electron distribution with a local internal electrostatic field (IEF), and we demonstrate artificially created and manipulated second harmonic generation (SHG) in a centrosymmetric optical material, a superimposed Co2+- and Mo6+-doped BiVO4 thin film with 2/m point group symmetry, where a homojunction producing tunable effective polarization is formed. The SHG was characterized and tuned by IEF. This work breaks the structural symmetry constraint on NLO materials. Besides, the phase-matching-like condition was realized for the further improvement of the efficient frequency conversion. Because polarization is also a prerequisite for many other functions besides SHG, we believe that this work should provide some inspiration for the further development of optoelectronic, photonic, and electronic materials.

Though titanium-based metal-organic frameworks (MOFs) are declared to be relatively water stable, their framework gradually collapses in water within days due to the attack of OH− to O Ti O bond. For practical applications of titanium-based MOFs, it is crucial to solve their instability problem in water. We searched for a simple and efficient method to enhance the stability of titanium-based MOFs in water by using Ti-ATA (ATA = 2-aminoterephthallate ion) as a representative titanium-based MOF. Here, we show that the stability of Ti-ATA in water is greatly improved nearly without affecting its porosity and photocatalytic activity by treating it with aqueous solutions containing metal ions of empty d orbitals (Y3+, La3+, Ce3+, Nd3+ and Tm3+) or partially-filled d orbitals (Cr3+).

Herein, the novel CaO/MgO CO2 sorbent was fabricated from carbide slag and dolomite by the combustion method during the calcium looping process. The carbide slag is a precursor of CaO, and dolomite is a precursor of both MgO and CaO. The effects of the mass ratio of the carbide slag to dolomite, calcination conditions and presence of steam during carbonation on the CO2 capture performance of the novel CaO/MgO sorbent were studied during the calcium looping cycles. When the mass ratio of the carbide slag to dolomite was 74 : 26, the resulting CaO/MgO sorbent having the mass ratio of CaO to MgO = 90 : 10 achieved highest CO2 capture capacity that was retained at 0.52 g g−1 after 20 cycles (carbonation in 15% CO2/85% N2 at 700 °C for 20 min; calcination in 100% N2 at 850 °C for 10 min), which was higher than those of the carbide slag and other reported CaO/MgO sorbents prepared from analytical reagents. Compared with that of the sample calcined under pure CO2 at 950 °C, the CO2 capture capacity of the CaO/MgO sorbent calcined in pure steam at 800 °C is apparently higher. This novel CaO/MgO sorbent fabricated from industrial waste and dolomite exhibits a more porous microstructure, which is promising for the calcium looping process for CO2 capture.

Effective and selective removal of Pb(II) from aqueous solution is highly desirable, but it is still a great challenge. We report here a water stable metal-organic frameworks (CAU-7-TATB), and the ligands contain N, which provides binding sites for metal ions. CAU-7-TATB exhibits fast adsorption kinetics, high adsorption capacity towards Pb(II). More importantly, CAU-7-TATB remains high prior adsorption towards Pb(II) in the presence of interfering ions like Cr(III), Co(II), Ni(II), Mn(II), Zn(II), Mg(II) and Ca(II), which is potentially applicable in removing Pb(II) from industrial water.

Ethylene (C2H4) is harmful for storage and fresh-keeping of fruits and vegetables. Photocatalytic technology is an effective and environmentally friendly approach for degrading ethylene. Herein, we first report the synthesis of a WO3 photocatalyst with high photocatalytic activity and stability using synergetic internal Fe3+ doping and superficial Pt loading for ethylene degradation under visible-light irradiation. Internal Fe3+ doping not only enhances the visible-light absorption but also improves the stability to some degree due to more positive reduction potential of Fe3+/Fe2+ than that of W6+/W5+ and separation efficiency of the photo-generated carriers. Furthermore, the loading of Pt as a co-catalyst through the photo-reduction of H2PtCl6 on the surface of Fe-doped WO3 promotes the effective transfer of photo-generated electrons and reduces the photo-corrosion of WO3. Due to the synergistic effect, extremely high degradation speed can be achieved by doping 0.25 mol% Fe and loading 0.75 wt% Pt for WO3, which exceeds that of pristine WO3 by about 3.3 times under visible-light irradiation. In addition, due to the excellent stability of Pt@Fe-doped WO3, it has good industrial application prospects in the field of photocatalysis.

We constructed a composite electrode by depositing a C/Ag mixture containing a tiny amount of 20 nm Ag NPs (∼0.5 wt%) on anodized Zn (AZ) metal. The AZ/C/Ag electrode exhibits greatly enhanced CO selectivity (∼86%) and activity (∼7.3 mA cm−2) on comparison with the GCE/C/Ag electrode (∼24% and ∼2.3 mA cm−2). The experimental results show that the enhanced CO2 reduction performance of the AZ/C/Ag electrode is attributed to the synergistic effect of AZ, C and Ag. Density functional theory calculations indicate that the enhanced CO selectivity may originate from the enhanced stabilization of CO2 and COOH* on the AZ/C/Ag electrode surface. This electrode also shows great mass activity and stability for CO2 reduction. Our work provides a new and simple way to fabricate efficient catalysts with high selectivity, activity and stability for electrocatalytic CO2 reduction.

Trinickel nitride as a kind of promising hydrogen evolution reaction (HER) electrocatalyst has attracted much attention in recent years due to its high electrical conductivity and low cost. Herein, we designed and synthesized a novel and efficient Ni3N@VN–NF composite by nitriding treatment of a NiV-LDH precursor. The obtained electrode exhibits superior performances including a much lower overpotential of 56 mV at 10 mA cm−2 and Tafel value of 47 mV dec−1 compared to pure Ni3N–NF and VN–NF electrodes. The Ni3N@VN–NF composite as a cathode and a conventional OER electrode NiFe-LDH–NF as an anode were combined to form a complete water-splitting system. The voltage at 10 mA cm−2 is about 1.55 V, which is superior to the voltage value reported in many literature studies. In addition, the two-electrode system exhibits excellent durability after as long as 50 hours of operation.

In this paper, n-type Ag2ZnSnS4 (AZTS) thin film was prepared by a simple electrodeposition and in situ sulfurization method on Mo-mesh substrate. Pristine AZTS photoanode yielded a photocurrent density of 4.0 mA cm−2 at 0.6 V vs. RHE. In order to improve the stability of Ag2ZnSnS4 photoanode, TiO2 offering more protection against the photo corrosion was deposited through an atomic layer deposition (ALD) process. IPCE measurements were used to evaluate solar energy utilization efficiencies of AZTS and TiO2/AZTS photoanodes, which showed 25% and 20% IPCE (510–530 nm) in water splitting reaction, respectively. The analysis of gas yield determined that the faradaic efficiency during the H2 evolution process was over 90%. Furthermore, the reasons for the high photoelectrochemical performance of AZTS/Mo-mesh and mechanism of PEC H2 evolution in system are discussed below.

In this study, we synthesized noble metal-free Co3O4 as a cocatalyst for a modified ZnO nanorod photocatalyst to achieve efficient ethylene degradation under light irradiation. The Co3O4-decorated ZnO nanorods demonstrate photocatalytic activity for ethylene oxidation that is better than that of pure ZnO and even better than that of the noble metal-based RuO2-modified ZnO. Furthermore, Co3O4-modified ZnO exhibits good stability in a six-cycle experiment. Measurement results indicate that the Co3O4 nanoparticles can effectively promote the transfer and inhibit the recombination of photogenerated electrons and holes during the photocatalytic reaction. Therefore, the Co3O4-modified ZnO nanorod photocatalyst displays excellent photocatalytic properties for ethylene degradation and can effectively realize the complete mineralization of ethylene molecules.

In this work, we developed a simple method to fabricate BiVO4 photoanode consisted of mesoporous nanoparticles (meso-BVO) by using P123 as a pore maker. Owing to the unique mesoporous nanostructure, meso-BVO exhibits higher BET surface areas, shorter hole transit distance and higher electrical conductivity than does pristine BiVO4 photoanode (BVO) consisted of solid nanoparticles. As a result, the charge separation efficiency and PEC performances of meso-BVO have been greatly improved. Meso-BVO yields a photocurrent of 2.19 mA/cm2 (1.23 V vs RHE) and IPCE of 39% (420 nm), which is 2.52 and 2 times as high as that of pristine BVO. With the assistance of Mo6+ ions doping and Co-Pi, the PEC performances could be further improved by addressing the inefficient electron transport and slow water oxidation kinetics. Co-Pi/Mo:meso-BVO yields a photocurrent of 4.57 mA/cm2 (1.23 V vs RHE) and IPCE value of 65% (420 nm). The enhanced PEC performance can be mainly ascribed to the perfect charge separation in the bulk of Co-Pi/Mo:meso-BVO photoanode. Our work provides a simple method to fabricate high efficient BiVO4 photoanodes consisted of mesoporous nanoparticles with enhanced bulk charge separation efficiencies.

Au nanoparticle (NP)- and CdS quantum dot (QD)-codecorated In2O3 nanosheets, assembled into flowerlike structure (In2O3/Au/CdS), were synthesized to facilitate photocatalytic H2 production. The optimized In2O3/Au4/CdS-12 (4 wt % Au NPs and CdS QDs were deposited for 12 cycles) displays achieved a photocatalytic hydrogen generation ability of 17.23 μmol/h (10 mg of catalyst), which is 22.97, 5.08, and 5.05 times as high as that of pristine In2O3 (0.75 μmol/h), In2O3/Au4 (3.39 μmol/h), and In2O3/CdS-12 (3.41 μmol/h), respectively. This significant improvement of H2 generation rate can be attributed to the following factors: the heterojunction at the In2O3–CdS interface and the Schottky barrier at the interface between In2O3–Au and CdS–Au improves the migration and separation of charge carriers, and the surface plasma resonance (SPR) effect of noble metal Au NPs enhances the light harvesting capacity of In2O3 and boosts the generation of hot electrons, efficiently improving the utilization rate of sunlight.

The electrocatalysts with low-cost, good stabilities, rich reserves and efficient activities are required to replace Pt-based materials for the hydrogen evolution reaction. Herein, we synthesize the low-cost MoS2/Ni3S2 heterostructure on Ni foam with efficient HER activity and good stability through optimizing the sulfur sources selection among thioacetamide (TAA), L-cysteine and thiourea. The different sulfur sources have a very important influence on the structures and morphologies of NF-MoS2/Ni3S2 composites, which may attribute to the different selective combining capacities of sulfur sources with Na2MoO4 and Ni foam. By contrast, NF-MoS2/Ni3S2-TAA shows relatively lower overpotential of 91 mV at 10 mA cm−2 and Tafel slope of 48.62 mV dec−1 than those of NF-MoS2/Ni3S2-L-cysteine (overpotential of 148 mV at 10 mA cm−2 and Tafel slope of 68.81 mV dec−1) or NF-MoS2/Ni3S2-thiourea (overpotential of 187 mV at 10 mA cm−2 and Tafel slope of 93.41 mV dec−1). The superior HER activity of NF-MoS2/Ni3S2-TAA is benefit from the higher MoS2 content and larger electrochemically active surface area. Optimizing the sulfur source selection can realize the efficient electrocatalytic hydrogen evolution of MoS2/Ni3S2 heterostructure which has an important guiding significance for the practical application in the future.

Carbide slag pellets fabricated by bagasse templating using extrusion-spheronization were proposed to simultaneously remove SO2/NO from flue gas. The effects of the reaction temperature, O2 concentration, mass ratio of bagasse to carbide slag and particle size on the simultaneous SO2/NO removal performance of carbide slag pellets were investigated in a bubbling fluidized bed reactor. CaO in the carbide slag pellets has a significant promotion effect on NO reduction by CO. SO2 and NO are completely removed by the carbide slag pellets at 825–875 °C. The presence of O2 in the reaction gas results in an adverse effect on NO removal by carbide slag pellets, while it leads to a positive effect on SO2 removal. With an increase in the mass of bagasse in the pellets, the duration for the complete NO removal becomes longer and the porosity of the pellets appears higher. Carbide slag pellets with a smaller particle size possess a higher NO removal capacity. The higher mass ratio of bagasse to carbide slag leads to a larger surface area and pore volume of the pellets during SO2/NO removal process but results in a slight decrease in the attrition resistance. Carbide slag pellets by bagasse templating for simultaneous SO2/NO removal seems promising in the industrial application.

NiV-LDH as a novel electrode material has rarely been investigated in the energy storage field. Herein, novel ultrathin NiV-LDH was designed and synthesized, which displays high specific capacitance but poor stability. To further improve the stability, NiV-LDH was transformed to the sulfide named NiV-S through an ion exchange reaction (S2− replaces OH−). The obtained NiV-S maintains the ultrathin (5 nm in thickness) and porous structure, and displays higher specific capacitance (2270.4 F g−1 at 2 A g−1), compared to NiV-LDH (1502 F g−1 at 2 A g−1). What is more improtant is that the cycling stability of NiV-S is much higher than NiV-LDH, (91.9% retention after 10,000 cycles for NiV-S vs only 63% retention after 5000 cycles for NiV-LDH). The asymmetric supercapacitor assembled using ultrathin porous NiV-S as the positive electrode and activated carbon (AC) as the negative electrode was found to deliver a maximum energy density of 51 W h kg−1 at a power density of 1600 W kg−1 and 12 kW kg−1 at 23.7 W h kg−1. In addition, 98.5% of the initial capacitance retains after 10,000 continuous cycling.

Carbide slag is an industrial waste generated from ethylene gas production in chlor-alkali plants. Here, a novel system coupling calcium looping and CaO/Ca(OH)2 thermochemical heat storage using carbide slag were proposed to simultaneously capture CO2 and store heat. For CaO/Ca(OH)2 thermochemical heat storage, the hydration/dehydration performance of original carbide slag and carbide slag that experienced calcium looping cycles for CO2 capture was investigated. The performances of the two types of carbide slag with and without chlorine were compared. The dehydration conversions of carbide slag improved with the increase of dehydration temperature. The chlorine content has no apparent effect on the hydration/dehydration performance of original carbide slag. However, for CO2 capture, carbide slag with high chlorine content shows lower carbonation conversion than that of carbide slag without chlorine. The hydration/dehydration conversions of carbide slag that experienced CO2 capture cycles are lower than those of original carbide slag. For carbide slag with chlorine, the hydration conversion can be improved by more than one CO2 capture cycle. Therefore, carbide slag that experienced various CO2 capture cycles is still suitable to be used in CaO/Ca(OH)2 thermochemical heat storage although calcium looping has an adverse effect on the hydration/dehydration performance of carbide slag.

Surface engineering is of importance to reduce the reaction barrier of oxygen evolution reaction (OER). Herein, the NiFe Prussian blue analogue (NiFe-PBA)-F catalyst with a multilevel structure was obtained from NiFe-PBAs via a fluorination strategy, which presents an ultralow OER overpotential of 190 mV at 10 mA cm-2 in alkaline solution, with a small Tafel slope of 57 mV dec-1 and excellent stability. Interestingly, surface fluorination engineering could achieve a controllable removal of ligands of the cyan group, contributing to keep the framework structure of NiFe-PBAs. Particularly, NiFe-PBAs-F undergoes a dramatic reconstruction with the dynamic migration of F ions, which creates more active sites of F-doped NiFeOOH and affords more favorable adsorption of oxygen intermediates. Density functional theory calculations suggest that F doping increases the state density of Ni 3d orbital around the Fermi level, thus improving the conductivity of NiFeOOH. Furthermore, based on our experimental results, the lattice oxygen oxidation mechanism for NiFe-PBAs-F was proposed. Our work not only provides a new pathway to realize the controllable pyrolysis of NiFe-PBAs but also gives more insights into the reconstruction and the mechanism for the OER process.