Semiconductor photocatalysis can utilize solar energy for clean energy conversion, but the catalytic efficiency is often unsatisfactory due to limited photo response and efficient separation of ...photogenerated carriers. In this work, 3D porous carbon nitride (3DPCN) composited oxygen vacancy‐induced indium oxide (3DPCN/VO‐In2O3) was successfully prepared and analyzed by some characterization methods. Meanwhile, the performance of photocatalytic nitrogen fixation was further investigated. X‐ray photoelectron spectroscopy and X‐Ray diffraction (XRD) confirmed the successful preparation of the composites and revealed the electron flow direction; scanning electron microscopy (SEM) and transmission electron microscopy showed the surface structure of the composites; diffuse reflectance spectroscopy and temperature programmed desorption (TPD) revealed the energy band position and adsorption mechanism; electron paramagnetic resonance (EPR) characterization confirms the successful construction of oxygen vacancies; and electrochemical impedance spectroscopy, photoluminescence, and other photochemical characterization results showed that 3DPCN/VO‐In2O3 band gap is narrower and more effective in capturing light than other materials, improving the photocatalytic nitrogen fixation ability. The test results show that the nitrogen fixation capacity of 3DPCN/VO‐In2O3 can reach a maximum value of 156 within 2 h. This result demonstrates that the modification of carbon nitride improves its nitrogen fixation effect, and the introduction of oxygen vacancy‐induced In2O3 improves the light absorption performance and is advantageous to the separation of photogenerated charge carriers.
Z‐scheme 3D porous carbon nitride/oxygen vacancy indium oxide (3DPCN/Vo‐In2O3) photocatalyst was prepared by supramolecular assembly and solvothermal method for nitrogen fixation process, which makes the process more environmentally friendly and efficient.
•A series of NGNS samples were synthesized by hydrothermal method.•NGNS was characterized by UV–vis, TG, XRD, Raman, HRTEM, SAED and XPS methods.•The adsorption kinetic and isotherm models of NGNS ...toward CR were investigated.•The adsorbent can be separated from system effectively and easily.•The prepared NGNS has potential application for the CR dye treatment.
A series of NiO/graphene nanosheets adsorbents (NGNS) were synthesized by a facile hydrothermal method, and characterized by UV–vis, XRD, TG, TEM, HRTEM, Raman, SAED and XPS methods. The NGNS was applied to deal with wastewater solution containing Congo Red (CR); and adsorption efficiency attained 99.56% at optimum condition. The adsorption kinetic and isotherm of adsorbent toward CR were investigated. The results indicated that pseudo second-order kinetic model and the equilibrium data were well fitted by Redlich–Peterson model. The adsorbent can be separated from system effectively and easily. The prepared adsorbent has potential application for the wastewater treatment containing CR azo-dye.
Plant community structure and microbial ecological functions of alpine steppe in Northern Tibet are susceptible to variations in the natural environment and anthropogenic activities. In recent times, ...the alpine steppe in Northern Tibet has been severely degraded, that is, plant biodiversity was reduced and plant coverage declined. It is crucial to restoring the degraded alpine steppe in Northern Tibet to maintain the sustainable development of the environment and social economy. This study aimed to evaluate the ecological engineering benefits of four types of ecological restoration treatments: (a) independent treatment of sowing plant seeds; (b) combined treatments with (a) and fertilized microbial inoculum; (c) combined treatments with (a) and spraying hydrophilic polyurethane (which can enhance the ability of moisture retention, fertility, and temperature in the soil subsystem); and (d) the comprehensive treatments with (a) and fertilized microbial inoculum and spraying hydrophilic polyurethane. Noting their effect on plant growth performance, plant taxonomic and functional diversity, soil physicochemical properties, and soil microbial diversity in the degraded alpine steppe. Plots where no seeds were planted and no other amendments were applied were selected as experimental controls. Plant height, leaf size, plant taxonomic and functional diversity, total carbon and nitrogen contents, soil bacterial and fungal diversity were significantly enhanced under the four ecological restoration treatments. Plant growth performance (in particular, competitiveness for sunlight acquisition and leaf photosynthetic area), and soil fertility were significantly enhanced under the four treatments. The improved plant taxonomic and functional diversity and soil microbial diversity could facilitate the biological communities in degraded alpine steppe to develop better ecological functions, especially community stability. Meanwhile, the combination of all three treatments was found to be the best among all treatments applied in this study. This can help restore the degraded alpine steppe in Northern Tibet.
Solar‐driven reduction of nitrogen to ammonia is a promising green approach and is considered as a sustainable alternative to the Haber–Bosch process. Carbon nitride (g‐C3N4) is an ideal non‐metallic ...semiconductor photocatalyst for photocatalytic N2 reduction reaction (p‐NRR). In this work, we designed a simple supramolecular self‐assembly method to prepare copper‐doped porous graphitic nitride (Cu@pg‐C3N4) photocatalysts. The synergistic semiconductor and metal interactions enabled the obtained Cu@pg‐C3N4 to achieve larger specific surface area, more efficient photogenerated carrier separation, and stronger photoreduction ability. The specific surface area of Cu@pg‐C3N4 increased from 5.69 to 75.76 μmol/L, exposing more active sites compared to bulk g‐C3N4. The NH4+ production rate of the obtained Cu@pg‐C3N4 was 150.47 μmol/L, which is 20 times higher than that of the bulk carbon nitride, exhibiting excellent N2 photofixation ability. These findings highlight the significant progress that can be achieved by metal supramolecular network modification strategies in harnessing the potential of carbon nitride for photocatalytic reduction applications.
A highly efficient zinc oxide/graphene‐like tungsten disulphide nanosheet (ZnO/WS2) was synthesized by a facile two‐step method and characterized via XRD, SEM, TEM, XPS, BET, UV‐Vis DRS, PL, etc. The ...photocatalytic activity of the ZnO/WS2 photocatalyst was estimated via the degradation of Rhodamine B (RhB) dye under 500 W tungsten lamp radiation. Compared with ZnO, ZnO/WS2 photocatalyst presented a high degradation efficiency (95.71 %) within 120 min under visible‐light irradiation, indicating that ZnO/WS2 photocatalyst had excellent photocatalytic activity. Photocatalytic reaction followed the first‐order model kinetics, and ZnO/WS2 photocatalyst remained a relatively higher photocatalytic activity after four successive recycles, which verified that the structure of ZnO/WS2 photocatalyst was stable and had potential applications in the removal of dye wastewater. At last, the possible mechanism for the photocatalytic degradation of dyes over ZnO/WS2 photocatalysts was also discussed.
An energy-efficient and environmentally friendly nitrogen fixation process is urgently needed to solve problems of high energy consumption and high emissions in the traditional ammonia industry. In ...this work, a Z-scheme porous g-C
3
N
4
/ZnFe
2
O
4
photocatalyst was synthesized, characterized and employed for N
2
photofixation. Temperature programmed desorption characterization confirmed that the adsorption capacity of nitrogen was improved for the porous structure. From N
2
photofixation evaluation experiments, the highest ammonia production efficiency can reach 147.33 μmol/L within 120 min. Photocatalytic performance is greatly improved because of the increasing of specific surface areas, enhancement of N
2
adsorption ability and synergistic effect of Z-scheme photocatalytic system. In the ammonia production process of the research, visible light is used as energy; N
2
and H
2
O are used as raw materials, which possesses a good application potential due to the advantages of being energy-efficient, environmentally friendly and pollution-free.
A novel water-soluble adsorbent (S-Me/MA) was prepared from melamine and maleic anhydride by two steps. The structure of material was characterized by FT-IR spectroscopy, SEM, and 1H NMR. The S-Me/MA ...was applied to deal with wastewater solution containing malachite green (MG). The influences of adsorbent dose, temperature, pH and contact time were investigated. At the same time, the adsorption kinetic and isotherm of S-Me/MA toward malachite green were investigated. The results indicated that the adsorption of malachite green was in line with pseudo-second order kinetics equation. Langmuir isotherm equation can be a fine description of the removal process. KCI Citation Count: 28
