3N4 Hybrid Research Articles

Recent Progress in Porphyrin/g-C3N4 Composite Photocatalysts for Solar Energy Utilization and Conversion.

Transforming solar energy into chemical bonds is a promising and viable way to store solar energy. Porphyrins are natural light-capturing antennas, and graphitic carbon nitride (g-C3N4) is an effective, artificially synthesized organic semiconductor. Their excellent complementarity has led to a growing number of research papers on porphyrin/g-C3N4 hybrids for solar energy utilization. This review highlights the recent progress in porphyrin/g-C3N4 composites, including: (1) porphyrin molecules/g-C3N4 composite photocatalysts connected via noncovalent or covalent interactions, and (2) porphyrin-based nanomaterials/g-C3N4 composite photocatalysts, such as porphyrin-based MOF/g-C3N4, porphyrin-based COF/g-C3N4, and porphyrin-based assembly/g-C3N4 heterojunction nanostructures. Additionally, the review discusses the versatile applications of these composites, including artificial photosynthesis for hydrogen evolution, CO2 reduction, and pollutant degradation. Lastly, critical summaries and perspectives on the challenges and future directions in this field are also provided.

Co3O4 Nanosheet/g-C3N4 Hybrid Photocatalysts for Promoted H2 Evolution

Co3O4 is an attractive semiconductor in the photocatalytic field due to its proper band gap; however, its energy level structure is mismatched for H2 evolution. Herein, the Co3O4-based photocatalysts, Co3O4 nanosheet/g-C3N4 hybrids, were successfully prepared by an ultrasonic self-assembly method for enhanced photocatalytic H2 evolution. The optimized hybrid with 20 wt % g-C3N4, 20-CNCo, displayed the best photocatalytic performances, and the average H2 evolution rate was 134.6 μmol·g–1·h–1. The enhanced photocatalytic H2 evolution activities of 20-CNCo were due to the formation of heterojunctions between Co3O4 nanosheets and g-C3N4, which can increase the optical absorption ability, promote the separation of photogenerated charges, accelerate the electron transfer, and prolong the lifetime of the excited electrons. Moreover, following the unique step-scheme (S-scheme) charge transfer mechanism, the strong redox ability of the Co3O4 nanosheet/ g-C3N4 hybrid was retained, which was beneficial to the H2 evolution. This work provides strategies for designing active catalysts for photocatalytic reactions.

Perovskite LaMnO3 Composite Graphene Carbon Nitride g-C3N4 Improves the Photocatalytic Performance of Tetracycline Degradation

With the extensive use and improper treatment of antibiotics, antibiotic pollution in aquaculture wastewater has become increasingly severe. Tetracycline antibiotics have become one of the most commonly used fishery antibiotics. In this study, a Z-scheme heterostructure LaMnO3/g-C3N4 was constructed by the sol–gel method as a photocatalyst to degrade tetracycline, and the influence of anions on the degradation effect was investigated. The LaMnO3/g-C3N4 hybrid was successfully constructed by scanning electron microscope, Fourier transform infrared spectrum, and X-ray diffraction. The results of degradation experiments demonstrated that the maximum tetracycline degradation efficiency of LaMnO3/g-C3N4-10 (LMO/CN-10) was 80%, the removal rate of TC decreased from 71% to 48% when the concentration of chloride ions increased from 0 mM to 10 mM, and the removal rate of TC decreased from 75% to 28% when the concentration of carbonate ions increased from 0 mM to 10 mM. This enhanced photocatalytic activity was attributed to the formation of a Z-scheme structure that promoted the separation of photoinduced electron holes while maintaining its own strong redox ability. Finally, the photocatalytic mechanism was designed based on the free radical trapping experiment, electrochemical impedance, and photoluminescence spectra, providing an opportunity for the construction of a new photocatalyst for the treatment of aquaculture tailwater in the future.

Effective sonochemical synthesis of titanium nitride nanoflakes decorated graphitic carbon nitride as an efficient bifunctional electrocatalyst for HER and OER performance

The development of highly efficient bifunctional electrocatalysts for overall water splitting is a desirable and challenging task. Herein, we reported the preparation of catalytic site-rich titanium nitride (TiN) decorated graphitic carbon nitride (g-C3N4) hetero nanostructure using a simple ultrasonication process. The as-prepared TiN/g-C3N4 hybrid was characterized by various analytical and spectroscopic techniques such as XRD, FT-IR, SEM, HR-TEM, and XPS analysis. The TiN/g-C3N4 hybrid exhibited remarkable bifunctional activity towards both hydrogen evolution reaction (HER) with an overpotential of (−0.35 V), and for oxygen evolution reaction (OER) it requires (0.32 V) to reach current density of 10 mA cm−2. And also, the above outcome result further confirmd from electrochemical impedance spectroscopy. The TiN/g-C3N4 composite shows high electrical conductivity which is mainly due to the presence of synergistic effect between the metal nitride and carbonaceuos material. Specifically, the incorporation of g-C3N4 provides support for TiN, and the nitrogen atoms in both materials will enable additional catalytic sites for the transport of electrons during the water-splitting pro

Heterostructured 2D/2D ZnIn2S4/g-C3N4 nanohybrids for photocatalytic degradation of antibiotic sulfamethoxazole and photoelectrochemical properties

In recent years, antibiotic drugs have been extensively used owing to increased industrial growth, and this has created issues related to drinking water and a green environment. Different techniques have been used to resolve these issues, among which heterogeneous photocatalysis has been widely explored for the elimination of toxic compounds from wastewater resources. In this study, ZnIn2S4, g-C3N4, and ZnIn2S4/g-C3N4 hybrid heterostructured composites are synthesized via hydrothermal method and used these (i) for the removal of antibiotic sulfamethoxazole pollutant and (ii) photoelectrochemical water oxidation. The nanomaterials were characterized using X-ray diffraction, Scanning electron microscopy, transmission electron microscopy, and UV–vis spectroscopy. The developed hybrid heterostructured composites were able to degrade sulfamethoxazole pollutants as well as offer improved photoelectrochemical properties compared to pristine samples. The catalytic performance of the materials developed under visible light irradiation was greatly improved for the degradation of the antibiotic drug up to 89.4% in 2 h. Moreover, the hybrid heterostructured photoelectrode showed a better photocurrent density (8.68 mA/cm2) and exhibited ∼19.2 and 29.9 times greater photocurrent density than the pristine photoelectrodes. Such a considerably increased catalytic activity was attributed to the active separation of charge carriers and transmission. The study offers an innovative approach to develop effective catalysts, and for the degradation of sulfamethoxazole as well as the PEC properties for hydrogen production.

Construction of NiO/Ag/g-C3N4 nanosheet: Enhanced photocatalytic H2 evolution by the unique structure and synergistic effect of Ag and NiO

In this work, NiO/Ag/g-C3N4 hybrids with unique structure were designed and fabricated by a stepwise photoreduction and thermal treatment method. Herein, under the effect of electrostatic attraction, the NiO was mainly deposited on the surface of Ag quantum dots in the NiO/Ag/g-C3N4 hybrids (denoted as NACN-x, x was the mole ratio of NiO and Ag). Under visible light irradiation, the H2 evolution rate of the optimized hybrid NACN-1 was about 586 μmol•h−1•g−1. However, in the same conditions, the g-C3N4 had negligible H2 evolution property. Furthermore, in comparison with the other contrast materials, the H2 evolution rate of NACN-1 was about 3.5, 2.5 and 1.4 times than that of Ag/g-C3N4, NiO/g-C3N4 and NiO-Ag/g-C3N4 (prepared via one-step photoreduction method). According to the results of the optical-electrical property tests, characterizations of TEM and XPS, and theoretical calculation, the superior H2 evolution property of NACN-1 should profit from the unique structure and synergistic effect of NiO and Ag. Because the Ag quantum dots in NiO/Ag/g-C3N4 hybrid would act as electron trapping center to significantly improve the separation efficiency of photoexcited carriers. Meanwhile, the electrons would be consumed on the reactive sites of the close contacted NiO to produce H2.

Graphitic Carbon Nitride Nanosheets Decorated with Strontium Tungstate Nanospheres as an Electrochemical Transducer for Sulfamethazine Sensing

Sulfamethazine (SMZ) is one of the most frequently utilized sulfonamides, and it is regularly found in animal-derived foods, posing a health risk. Hence, developing a quick, easy, selective, and sensitive analytical method for on-site detection of SMZ is essential for improving food safety. Recently, transition-metal oxides have attracted great interest as promising sensors for detecting sulfamethazine due to their superior redox behavior, electrochemical activity, and electroactive sites. However, they tremendously suffer from poor electrical conductivity and electrochemical stability, which limits their commercial reality. Herein, a highly selective sensor consisting of two-dimensional (2D) graphitic carbon nitride nanosheet (g-C3N4) networks anchored to strontium tungstate nanospheres (denoted as SrWO4/g-C3N4) is developed for nonenzymatic sulfamethazine detection. When employed as the sensing platform, the SrWO4/g-C3N4 hybrid shows enhanced sensing performance with a fast response time, high sensitivity, low detection limit of 0.0059 μM, wide detection ranges from 0.2 to 600 μM, and prolonged cycle life of over 30 days. The sensor performs well in sulfamethazine in real sample analysis, reflecting its practical applicability. Such a performance may be attributed to the numerous electroactive sites, confined electronic structures, and high synergistic interaction between active SrWO4 species and the g-C3N4 matrix. This work demonstrates an innovative protocol for developing SrWO4/g-C3N4-based sensing platforms with nanoscale architectures and high interface configurations.

Ultrafine ZnCo2O4 QD-incorporated carbon nitride mediated peroxymonosulfate activation for norfloxacin oxidation: performance, mechanisms and pathways.

Recently, peroxymonosulfate (PMS)-based advanced oxidation processes (AOPs) are being actively investigated as a potential technology for water decontamination and many efforts have been made to improve the activation efficiency of PMS. Herein, a 0D metal oxide quantum dot (QD)-2D ultrathin g-C3N4 nanosheet (ZnCo2O4/g-C3N4) hybrid was facilely fabricated through a one-pot hydrothermal process and used as an efficient PMS activator. Benefiting from the restricted growth effect of the g-C3N4 support, ultrafine ZnCo2O4 QDs (∼3-5 nm) are uniformly and stably anchored onto the surface. The ultrafine ZnCo2O4 possesses high specific surface areas and shortened mass/electron transport route so that the internal static electric field (Einternal) formed in the interface between p-type ZnCo2O4 and the n-type g-C3N4 semiconductor could speed up the electron transfer during the catalytic reaction. This thereby induces the high-efficiency PMS activation for rapid organic pollutant removal. As expected, the ZnCo2O4/g-C3N4 hybrid catalysts significantly outperformed individual ZnCo2O4 and g-C3N4 in catalytic oxidative degradation of norfloxacin (NOR) in the presence of PMS (95.3% removal of 20 mg L-1 of NOR in 120 min). Furthermore, the ZnCo2O4/g-C3N4-mediated PMS activation system was systematically studied in terms of the identification of reactive radicals, the impact of control factors, and the recyclability of the catalyst. The results of this study demonstrated the great potential of a built-in electric field-driven catalyst as a novel PMS activator for the remediation of contaminated water.

Construction of g-C3N4/CdS/BiVO4 ternary nanocomposite with enhanced visible-light-driven photocatalytic activity toward methylene blue dye degradation in the aqueous phase

Herein, the ternary CdS/BiVO4/g-C3N4 (CBG) hybrid semiconductor photocatalyst was prepared via a hydrothermal technique. The synthesized photocatalysts were thoroughly characterized using powder XRD, XPS, FTIR, SEM, TEM, and UV-DRS to investigate the microstructural, morphological attributes, and optical properties. The photocatalytic activity of the ternary CBG hybrid semiconductor was assessed through the photodegradation of Methylene Blue (MB) aqueous dye under visible light. The outcomes exhibited that the CBG hybrid semiconductor showed excellent photocatalytic activity (about 94.5% after 120 min) compared to the results obtained with the pristine materials or the other composite (CdS/BiVO4). The enhancement of photocatalytic activity can be due to the construction of heterojunctions among g-C3N4, CdS, and BiVO4, which improves charge transfer efficiency and hence favors the degradation of organic dyes. Moreover, the as-prepared photocatalyst showed excellent stability after five cycles, indicating good stability and reusability. Subsequently, a possible photocatalytic mechanism was proposed based on the experimental results. The current investigation provides a promising strategy to promote photocatalytic activity to eliminate waterborne contaminants.

0D carbon dots intercalated Z-scheme CuO/g-C3N4 heterojunction with dual charge transfer pathways for synergetic visible-light-driven photo-Fenton-like catalysis

Photo-Fenton-like catalysis allows development of novel advanced oxidation technology with promising application in wastewater treatment. In this work, carbon dots (CDs) were intercalated between CuO nanoparticles and coralloid flower-like graphitic carbon nitride (g-C3N4) to fabricate a ternary CuO/CDs/g-C3N4 hybrid for synergetic visible-light-driven photo-Fenton-like oxidation. The CuO/CDs/g-C3N4 hybrid showed remarkable degradation efficiency towards recalcitrant organic contamination, excellent tolerance to realistic environmental conditions, exceptional stability and wide universality, declaring great potential for practical applications. •OH and •O2− radicals were demonstrated to be the primary contributors in the photo-Fenton-like system. Mechanism studies reveal dual charge transfer pathways in the Z-scheme CuO/g-C3N4 heterojunction assisted by interfacial electron transmission bridges of CDs, which can simultaneously boost the reduction of Cu2+ to Cu+ in the Fenton-like cycle and accelerate the Z-scheme electron flow from CuO to g-C3N4, leading to synergistic enhancement of the catalytic performance. This work would afford a feasible strategy to develop reinforced solar energy-assisted photo-Fenton-like catalysis systems for water remediation.

Synergistic utilization of magnetic rGO/NiFe2O4-g-C3N4 S-Scheme heterostructure photocatalyst with enhanced charge carrier separation and transfer: A highly stable and robust photocatalyst for efficient solar fuel (hydrogen) generation

Graphitic-C3N4 is the prime photocatalyst for solar energy conversion applications owing to its inexpensive, non-toxic, low gap energy, chemical and thermal stability. Herein, a rGO/NiFe2O4-g-C3N4 (RNC-3) hybrid heterostructure photocatalyst was fabricated to realize the effective charge carrier transfer and efficient solar fuel (H2) generation. The photocatalytic H2 generation activity was evaluated under solar light irradiation in the presence of triethanolamine (TEOA) as a hole scavenger. The optimized co-catalysts loadings are 15 wt% and 3 wt% for NiFe2O4 and rGO, respectively. The results obtained show that RNC-3 hybrid heterostructure is an efficient and stable photocatalyst towards water-splitting and presented H2 generation activity of 11,817 μmolg-1h-1, approximately ∼4 and 76 times higher than NiFe2O4-g-C3N4 and g-C3N4 nanosheets, respectively. Notably, the solar-to-hydrogen (STH) conversion efficiency of 2.44% was achieved, prominently surpassing many reported g-C3N4-based materials. This outstanding performance can be related to the substantial band gap reduction from 2.75 to 2.48 eV and significant PL quenching was observed after the incorporation of NiFe2O4 and rGO, which dramatically improved charge carrier separation and transfer, thereby enhancing the photocatalytic performance. Furthermore, RNC-3 exhibits convenient magnetic recovery, practical reusability, and high activity, making it a potential visible-light responsive photocatalyst for efficient water-splitting applications.

S-scheme 2D/2D FeTiO3/g-C3N4 hybrid architectures as visible-light-driven photo-Fenton catalysts for tetracycline hydrochloride degradation

Fabricating highly active and stable hybrid catalytic systems for pollutant degradation is challenging. Herein, we manufactured a series of FeTiO3/g-C3N4 hybrid architectures via self-assembly and used them as efficient visible-light-driven photo-Fenton catalysts for tetracycline hydrochloride degradation. The FeTiO3/g-C3N4 hybrid architecture with optimal photo-Fenton activity, which was synthesized by combining 200 mg of FeTiO3 with 1200 mg of g-C3N4, exhibited excellent recyclability for five photo-Fenton cycles. The catalytic mechanism of the photo-Fenton reaction over FeTiO3/g-C3N4 hybrid architectures was investigated by scavenging the active species generated during the reaction and analyzing the electronic paramagnetic resonance spectra of the reaction mixtures. The remarkable photo-Fenton activity of FeTiO3/g-C3N4 hybrid architectures was ascribed to the S-scheme charge transfer pathway generated via the construction of intimate interfacial contacts between FeTiO3 nanoplates and g-C3N4 nanosheets. We believe this study provides some useful insights into the design and fabrication of S-scheme photo-Fenton catalysts for environmental remediation.

Synthesis of TiO2/g-C3N4 Hybrid Photocatalyst and its Application for Degradation of Chlorophenol as Organic Water Pollutant

Synthesis of TiO2/g-C3N4 Hybrid Photocatalyst and its Application for Degradation of Chlorophenol as Organic Water Pollutant

Facile construction Z-scheme anatase/rutile TiO2/g-C3N4 hybrid for efficient photocatalytic H2 evolution under visible-light irradiation

Z-scheme anatase/rutile TiO2/g-C3N4 hybrids (denoted as LTARCN-x, x represents calcination temperature) were designed and synthesized by growing TiO2 nanorods on the surface of g-C3N4 utilizing impregnation-calcination method. Furthermore, through the etched effect of hydrochloric acid and calcination treatment, the as-prepared LTARCN-x possessed abundant pore structure and larger surface area, and the surface area of LTARCN-425 was 8.5 times than that of bulk g-C3N4. Meanwhile, the g-C3N4 would play a role of carrier to prevent from the aggregation of TiO2 nanorods. In addition, under visible light irradiation, the Z-scheme heterostructure would be constructed between the rutile TiO2 nanorod and g-C3N4 nanosheet, respectively. The optimized photocatalyst LTARCN-425 exhibited a preferable activity, the photocatalytic hydrogen production rate of LTARCN-425 was about 1031 μmol g−1 h−1, and it was about 6.3 and 13.6 times than that of g-C3N4 and TiO2, respectively. Moreover, the photocatalytic mechanism of the hydrogen production was studied intensively via designing fluorescent probe, Pt and PbO2 deposition experiment, and the characterizations of EPR, TEM, HRTEM and XPS.

Comparison of performance of CuI/g-C3N4 nanocomposites synthesized on Ni-foam and graphitic substrates as suitable electrode materials for supercapacitors

Within this study, which is a pioneer in what it is undertaking, the synergetic effect of copper iodide/graphitic carbon nitride (CuI/g-C3N4) hybrid nanocomposites as electrode materials which are highly conductive and transfer ions/electrons are being investigated as high-performance supercapacitors (SCs). CuI/g-C3N4 nanostructure is synthesized applying two various facile and simple methods combined namely sonochemistry and coprecipitation. Fourier transform infrared (FT-IR), X-ray diffraction (XRD), field emission scanning electron microscopy (FESEM), energy dispersive X-ray spectroscopy (EDX) spectral techniques are applied for morphology investigation, phase evaluation and purification analysis of synthesized nanostructure. CuI/g-C3N4 hybrid nanocomposite electrode is investigated on two different substrates, Ni-foam@CuI/g-C3N4 (NF@CuI/g-C3N4) and graphitic plate@CuI/g-C3N4 (GP@ CuI/ g-C3N4). Redox reaction, diffusion electron/ion, specific capacity, power and energy density, cycling stability of nanocomposites are evaluated through cyclic voltammetry (CV), electrochemical impedance spectroscopy (EIS) and galvanostatic charge–discharge (GCD). The attained NF@CuI/g-C3N4 and GP@ CuI/ g-C3N4 hybrid nanocomposites reveals perfect electrochemical proficiency with a great specific capacitance of 623 and 318 F/g at a current density of 1 A/g. Besides, these nominated electrodes depict a considerably well energy density of 17.5 and 34.2 Wh Kg−1, power density of 224 and 440 W kg−1 and ideal cyclic stability by maintain 85 % of their primary capacitance after 3000 and 1500 cycles respectively. This work intends to introduce an unprecedented strategy, applying a novel nanocomposite on two different substrates, and yet revealing an excellent electrochemical property as a result.

Photocatalytic Activity of TiO2/g-C3N4 Nanocomposites for Removal of Monochlorophenols from Water.

This research employed g-C3N4 nanosheets in the hydrothermal synthesis of TiO2/g-C3N4 hybrid photocatalysts. The TiO2/g-C3N4 heterojunctions, well-dispersed TiO2 nanoparticles on the g-C3N4 nanosheets, are effective photocatalysts for the degradation of monochlorophenols (MCPs: 2-CP, 3-CP, and 4-CP) which are prominent water contaminants. The removal efficiency of 2-CP and 4-CP reached 87% and 64%, respectively, after treatment of 25 ppm CP solutions with the photocatalyst (40TiO2/g-C3N4, 1 g/L) and irradiation with UV–Vis light. Treatment of CP solutions with g-C3N4 nanosheets or TiO2 alone in conjunction with irradiation gave removal efficiencies lower than 50%, which suggests the two act synergically to enhance the photocatalytic activity of the 40TiO2/g-C3N4 nanocomposite. Superoxide and hydroxyl radicals are key active species produced during CP photodegradation. In addition, the observed nitrogen and Ti3+ defects and oxygen vacancies in the TiO2/g-C3N4 nanocomposites may improve the light-harvesting ability of the composite and assist preventing rapid electron-hole recombination on the surface, enhancing the photocatalytic performance. In addition, interfacial interactions between the MCPs (low polarity) and thermally exfoliated carbon nitride in the TiO2/g-C3N4 nanocomposites may also enhance MCP degradation.

Controlled photoinduced electron transfer from g-C3N4 to CuCdCe-LDH for efficient visible light hydrogen evolution reaction

Ample visible-light response and efficient charge transfers in semiconductor heterojunction are still enslaved to the limited photocatalytic water splitting. In most cases, the rational design of hybrid composites tune in atomic level interaction led to remarkable stability and superior activity. Here, this work is a systematic investigation of metal ion substitution in the LDH and LDH/g-C3N4 hybrid composites for hydrogen evolution reaction (HER) under visible light. The construction of heterostructure not only facilitates the charge separation and transfer owing to the formed heterojunction through band gap engineering and tunable optical properties which are inherited from morphology of as grown CuCdCe-LDH over the exfoliated g-C3N4 but also provides plenty of surface active sites due the increased surface area photostability. The CuCdCe-LDH/g-C3N4 exhibits superior HER rate of 3.5 mmolg−1h−1 with AQY of 5.78% over their binary counterparts. The density functional theory calculations also suggest that the HER activity of CuCdCe-LDH is substantially enhanced by coupling with g-C3N4 the electrochemical results leading to high photocurrent response. The high photocatalytic activity of the composite was due to efficient photoexcited charge transfer process and the synergistic effect between CuCdCe-LDH and g-C3N4. These finding will open scopes for designing inexpensive high performance materials for broad applications of photocatalytic energy conversion.

Synergistic effect of NiS/g-C3N4 nanocomposite for high‐performance asymmetric supercapacitors

Fabricating a new electrode material with high capacitive aspects is critical to improving a high-performance energy storage device. The transition metal sulfide-based nanocomposite electrode materials are possible for the construction of high-performance hybrid supercapacitors owing to the large surface area and its peculiar Faradic battery-type charge storage behavior. In this work, the NiS/g-C3N4 hybrid was prepared through a one-pot hydrothermal method, and g-C3N4 was synthesized via a thermal method. The NiS/g-C3N4 shows the morphology of both sheet-like g-C3N4 and sphere-like NiS nanostructures. The compacted sheet and sphere structure of NiS/g-C3N4 hybrid composite shows outstanding electrochemical performance as a supercapacitor electrode. Consequently, the prepared NiS/g-C3N4 hybrid composite electrode materials reach their superior specific capacity (Cs) at 2661.25 C g−1 at 1 A g−1 in 3 M KOH aqueous electrolyte, which is comparatively higher than that of pure NiS spheres (722.50 C g−1 at 1 A g−1). The assembled NiS/g-C3N4//AC Hybrid device (HD) exhibited a maximum specific capacity of 181.8 C g−1 at 1 A g−1 and their energy density and power density of 53.09 W h kg−1 and 31537.5 W kg−1, respectively. The constructed NiS/g-C3N4//AC Hybrid device delivers outstanding cyclic retention of 95% after 10,000 cycles. The above results suggest that the NiS/g-C3N4 hybrid composite has good chemical stability, cyclic retention, and auspicious electrode material for the next generation of energy storage applications.

Watt-level beam combined diode laser systems in a chip-scale hybrid photonic platform.

Scaling up the power of on-chip diode lasers is of great importance for many emerging applications, such as integrated nonlinear optics, remote sensing, free space communication, infrared countermeasure, and light detection and ranging (LIDAR). In this manuscript, we introduce and demonstrate photonic integrated circuits (PIC) based beam combining methods to create power scalable, integrated direct diode laser systems. Traditional laser beam combining, including coherent beam combining (CBC) and wavelength beam combining (WBC), usually requires free space or fiber optical components, leading to bulky and complex systems. Instead, PIC based beam combining methods can greatly reduce the cost, size, weight, and power consumption (CSWaP) of next generation direct diode laser systems. We experimentally demonstrate four channel chip-scale CBC and WBC with watt-level on-chip power by using III/V-Si3N4 hybrid integration. Our results show that PIC based beam combining is very suitable for power scaling in a chip-scale platform.

Polyaniline/g-C3N4 hybrid nanoparticles: Fabrication, characterization and boosting bisphenol destruction and hydrogen gas evolution through direct S-scheme aspects

The conversion of intermittent sunlight energy into low cost alternative fuel source is a great challenge in the recent years. Herein, a novel polyaniline/g-C3N4 heterojunctions containing (1–5) wt % polyaniline are successfully synthesized in ultrasonic bath of 250 W intensity. The change in the crystalline, textural, nanostructure, elemental compositions and optical properties of the nanocomposites are well elaborated by XRD, XPS, N2-adsorption-desorption isotherm, DRS, HRTEM and PL. Polyaniline synthesized through oxidative polymerization in situ is successfully distributed in homogeneous population on graphitic carbon nitride nanosheets. Noticeably, incorporation of 3 wt% polyaniline on the g-C3N4 surface depresses the crystalline size and surface parameters, harvesting the visible light absorption and limiting the electron-hole recombination rate. 91% of bisphenol was decomposed on 0.1 g of photocatalyst containing 3 wt% polyaniline during 2 h of the photoreaction under sun simulator of intensity 300 W. The concentration of hydrogen gas evolved approach 4.43 mmolg−1h−1 which is eleven fold higher than that of pristine g-C3N4. Superoxide radicals and electrons conduction band are responsible for decomposition of BPA into eco-friendly species. The transfer of photogenerated electrons in S-scheme polyaniline/g-C3N4 heterojunction is more like “Step” which associated by production of internal electric field at the interface boundary However, the postulated scheme reveals that the production of hydroxyl group is restricted on the surface of PAN/g-C3N4 nanocomposite.