Application Of Graphitic Carbon Nitride Research Articles

Sensing applications of graphitic carbon nitride (g-C3N4) for sensing SO2 and SO3 – A DFT study

Gas sensors are instruments that detects and monitors the presence of harmful and toxic gases in the atmosphere. They are an essential tool for maintaining environmental health, air quality, and safety, and their invention has prompted an extensive research and advancement in the field of gas detection. The sensing and adsorption behaviour of graphitic carbon nitride are analyzed to detect noxious gases SO2 and SO3 using density functional theory. Upon absorption of SO2 and SO3 analytes on the surface of the carbon nitride (C6N8), moderate physiorption for the SO2 analyte (−37.11 kJ mol−1), and high chemisorption for SO3 analyte (−67.90 kJ mol−1) are observed. The interaction energies depict weak van der Waals forces that is further demonstrated by the noncovalent interaction index (NCI), symmetry perturbation theory (SAPT0) and quantum theory of atoms in molecules (QTAIM) analysis. Using the natural bond orbital analysis, UV–Vis analysis, electron localization function, molecular electrostatic potential, and density of state (DOS) analysis, the electronic properties of complexes were analyzed to determine the significant impacts of the adsorption of these analytes (SO2 and SO3) on the carbon nitride C6N8. Natural bond orbital analysis revealed that charge migration occurs from the carbon nitride C6N8 surface towards the analytes (SO2 and SO3) during complex formation that are −0.032 and −0.189 e−, for SO2@C6N8 and SO3@C6N8 complexes. The analytes (SO2 and SO3) behave as electrophiles and the carbon nitride C6N8 surface serves as a nucleophilic attack in both complexes. The chemical reactivity of both complexes was shown by the development of new excited states in the PDOS spectrum. At 300 K, the recovery period was calculated by applying the transition state theory to analyze the reusability of the carbon nitride C6N8 surface. Our finding provides a theoretical foundation for the possible use of carbon nitride C6N8 surface for gas sensors targeting significant air pollutants such as SO2 and SO3 in the environment.

Sensing applications of graphitic carbon nitride (C6N8) for nitrogen oxides: A DFT study

The absorption properties of molecules NOx onto monolayered C6N8 were investigated thoroughly with density functional theory. Detailed orbital, and reactivity analysis on C6N8 monolayer have shown that NO2 and NO were successfully adsorbed onto the C6N8 monolayer with considerable amount of adsorption energy and charge transfer. The electric conductivity of the C6N8 monolayer significantly increased due to the adsorption of the NO2 and NO, resulting in the semiconducting behavior of the material being turned into conducting behavior. It has been established that the absorption rate of NO2 and NO onto the C6N8 monolayer is moderate, making their desorption fairly simple, indicating potential in terms of C6N8 sensor’s reusability. Hence, C6N8 monolayer could be a promising candidate for sensing NO and NO2, which can be validated through further experimental studies.

Highly efficient photocatalytic removal of concentrated PEX, PAX and SIPX xanthates collectors by an immobilized nanostructured g-C3N4/ZnO low power backlighted module

This study provides a pathway to practical application of graphitic carbon nitride (g-C3N4)-based photocatalysts as a promising next-generation polymeric-based environmentally friendly two dimentional (2D) nano-photocatalyst under real conditions in a dark medium at a very high concentration of xanthates collectors. Ultra-low amounts photocatalyst loading, low-power visible LED light source and strong light-photocatalyst coupling also play important roles in practical photodegradation of pollutants. Herein, immobilized low metal-oxide loaded (LMOL) g-C3N4/ZnO backlighted photocatalytic module with 0.6 ± 0.1 g/m2 g-C3N4/ZnO loading was developed to degrade dark dyes, potassium ethyl xanthate (PEX), potassium amyl xanthate (PAX) and sodium isopropyl xanthate (SIPX) collectors. The LMOL g-C3N4/ZnO nanostructures were investigated by XRD, UV–vis, PL, FE-SEM and XPS. After an efficient decomposing of dark methylene blue and methyl orange, the photodegradation of PEX, PAX and SIPX was examined and the photodegradation mechanism of the xanthates was also investigated. The degradation efficiency of the photocatalytic module was up to 95 %, which remained unchanged after several cycles. The efficient photocatalytic removal of xanthates is due to the effective light-photocatalyst coupling in dark media and also well-established e-/h+ generation and separation in LMOL g-C3N4/ZnO heterojunction.

Recent advancements in synthesis and multi-functional catalytic applications of graphitic carbon nitride

ABSTRACT Graphitic carbon nitride (CN) is a versatile polymeric nanosheet that has gained significant attention due to its stability, tunable band structure, and eco-friendliness. This review explores recent advances in CN-based material design and construction, such as element doping, heterostructure formation, and surface sensitization, emphasizing their unique optoelectronic and charge transfer properties. Subsequently, their potential applications in photocatalysis for environmental remediation, and energy generation, as well as organic synthesis and medical diagnostics are also delved. This review critically explores these advances and their challenges, and offers future perspectives to enhance the performance of CN-based materials and contribute to a sustainable future.

Graphitic carbon nitride nanomaterials for high‐performance supercapacitors

AbstractGraphitic carbon nitride is a promising material as an electrode material for advanced electrochemical energy storage devices because of its controllable structure, physicochemical properties, and abundant active sites. However, its intrinsic properties as electrode materials can not be fully expressed owing to limited electrical properties, which impede charge transfer and material exchange inside devices. During the past decade, the challenge has been addressed through material engineering strategies, such as exfoliation and composition, and then advanced energy devices, such as supercapacitors, have been assembled. In this regard, a timely review of graphitic carbon nitride for high‐performance supercapacitors requires to be put forward for summarizing past studies and inspiring future research works as well. This review article summarizes recent progress in material synthesis and property regulation of graphitic carbon nitride nanomaterials and their application in assembling advanced supercapacitors with high energy density and superior working stability. Finally, based on existing research and our experimental experience, a perspective for directing future research has been presented concerning material synthesis and electrochemical application of graphitic carbon nitride.

Electrocatalytic application of graphitic carbon Nitride(gCN) in boosting the performance of copper nickle tin Sulphide(CNTS) hierarchical structure

The growing demand for energy, as well as the impact on the environment as a result of human activity, has prompted a renewed focus on the development of cleaner alternative fuels. Because of its pure combustion products, hydrogen gas is being used as an alternative in the development of sustainable energy sources. A simple hydrothermal technique was used to prepare copper nickel tin sulphide (CNTS) decorated graphitic carbon nitride (gCN). CNTS-gCN samples were further prepared on different concentrations of gCN that varies from CNTS-gCN(10 mg–50mg) and analyzed under various characterization for its structural, morphological, and electrochemical properties. Field Emission Scanning Electron Microscopy (FESEM), Raman and HR-TEM (High Resolution- Transmitting Electron Microscopy) techniques were used to examine the morphology and surface structure of CNTS-gCN. Owing to its exclusive electrocatalytic property as low charge transfer resistance and high electrochemically active surface area, the composite material reveals a superior catalytic stability for the production of hydrogen energy. The hierarchical flower like structures were still maintained even after the addition of g-CN at different loading concentrations (10–50) respectively. The objective of this research is to prepare a new electrocatalyst based on CNTS with an increased HER activity.

One-step synthesis of porous thin-layered graphitic carbon nitride for enhanced photocatalytic dye degradation

The application of graphitic carbon nitride (g-C3N4) as a non-metallic photocatalyst for removing harmful pollutants in the wastewater environment has received considerable attention in recent years. Nevertheless, its low activity is primarily restricted by a high rate of charge carrier recombination. Herein, a green and straightforward method for synthesizing small-sized porous thin g-C3N4 nanosheets directly from urea solution has been developed. This new photocatalyst can effectively remove 99.3% of rhodamine B within 15 min, exhibiting a degradation rate 16.8 times greater than that of conventionally synthesized bulk g-C3N4, under visible light irradiation. Additionally, this photocatalytic efficiency is comparable or even superior to that of previously reported literature, while requiring significantly less catalyst usage. From the experimental results, we have confirmed that the outstanding structural property as well as the stronger oxidizability of the valence-band holes (h+) are responsible for its greater photocatalytic activity. Its increased specific surface area and abundant pore structure significantly improve contaminant adsorption and charge separation and transfer. Meanwhile, the positive shift of the valence band enhances the oxidation of photogenerated h+, resulting in higher photocatalytic activity. This work can provide newly insights for designing highly efficient and easily-constructed g-C3N4 photocatalysts for practical photocatalytic water treatment applications.

An innovative approach for landfill leachate treatment based on selective adsorption of humic acids with carbon nitride

Selective adsorption of humic acids is innovative in landfill leachate treatment, since it can both address the UV quenching substance (UVQS) problems and recover humic acids as liquid fertilizers applied in agriculture and forestry. However, due to lacking available adsorbents, it remains a great challenge. Herein, we evaluated the application of graphitic carbon nitride (g-CN) for selective adsorption of humic acids from landfill leachate. First, 10 types of leachate were considered and characterized, and the leachate contained humic acids of different contents. The common method was used to prepare g-CN with similar properties to the previously reported counterparts. Then, kinetics, isotherms, and removal for adsorption of the leachate by g-CN were studied. It was found that the adsorption was fast and controlled by the surface and intraparticle diffusion. For all the leachate, the removal of UV absorbance at 254 nm (UV254) was 30 ∼ 70%, much greater than that for total organic carbon. In particular, the UV254 removal was mainly contributed by the selective adsorption of humic acids with a high selectivity coefficient (>3.06). The recovery rate and purity of the adsorbed humic-like components were 100% in some cases. Finally, the mechanisms for selective adsorption were elucidated. The results revealed that, in addition to the major π-π interactions, the adsorption was affected by electrostatic interactions and hydrogen bondings, along with the newly proven conformation-variation effect. The findings will expand a promising direction for disposal of landfill leachate.

Facile synthesis of N vacancy g-C3N4 using Mg-induced defect on the amine groups for enhanced photocatalytic •OH generation

Photocatalysis offers opportunities to degrade recalcitrant organic pollutants without adding treatment chemicals. Nitrogen (N) vacancy is an effective point-defect engineering strategy to mitigate electron-hole recombination and facilitate hydroxyl radical (•OH) production via superoxide radical (O2•-) generation during photocatalytic application of graphitic carbon nitride (g-C3N4). Here, we report a novel strategy for fabrication of N-vacancy-rich g-C3N4 (NvrCN) via post-solvothermal treatment of Mg-doped g-C3N4. The addition of the Mg precursor during the polycondensation of urea created abundant amine sites in the g-C3N4 framework, which facilitates formation of N vacancies during post-solvothermal treatment. Elemental analysis and electron paramagnetic resonance spectra confirmed a higher abundance of N vacancies in the resultant NvrCN. Further optical and electronic analyses revealed the beneficial role of N vacancies in light-harvesting capacity, electron-hole separation, and charge transfer. N vacancies also provide specific reaction centers for O2 molecules, promoting oxygen reduction reaction (ORR). Therefore, •OH generation increased via enhanced formation of H2O2 under visible light irradiation, and NvrCN photocatalytically degraded oxytetracycline 4-fold faster with degradation rate constant of 1.85 × 10−2 min−1 (light intensity = 1.03 mW/cm2, catalyst concentration = 0.6 g/L, oxytetracycline concentration = 20 mg/L) than pristine g-C3N4. Overall, this study provides a facile method for synthesizing N-vacancy-rich g-C3N4 and elucidates the role of the defect structure in enhancing the photocatalytic activity of g-C3N4.

Potassium-Derived Charge Channels in Boron-Doped g-C3N4 Nanosheets for Photocatalytic NO Oxidation and Hydrogen Evolution.

The application of graphitic carbon nitride (g-C3N4) in photocatalytic NO oxidation was limited due to severe recombination of photogenerated carriers and low concentration of oxidizing species. In this work, K and B were introduced into the interlayer and in-plane framework of g-C3N4 to address this challenge through the thermal polymerization process. The synthesized K-doped B-g-C3N4 nanosheets exhibited expanded light absorption and low charge recombination efficiency. In addition, the doping of K and B reduced the band gap of g-C3N4, which corresponded to enhanced light absorption. B was introduced into the in-plane structure by replacing C atoms, which adjusted the in-plane electron distribution. K was inserted into the interlayer by binding to the N and C atoms of adjacent layers. K-derived electron transfer channels were constructed, which increased electron delocalization and expanded the π-conjugate system. More electrons were transferred through the interlayer channels and were involved in the reaction process. The severe carrier recombination and weak transfer were improved due to the synergistic effect of K and B doping. K-doped B-g-C3N4 nanosheets exhibited enhanced generation of superoxide radicals and hydroxyl radicals, which played a key role during NO oxidation. The photocatalytic NO oxidation efficiency of codoped g-C3N4 nanosheets reached 61%, which was 2.1 and 1.2 times of that of pristine g-C3N4 and B-doped g-C3N4, respectively. The codoped g-C3N4 sample still exhibited stable photocatalytic NO oxidation efficiency after five cycles. This result provided a potential idea for improving the charge distribution and transfer of layered materials by codoping metallic and nonmetallic elements and for photocatalytic NO oxidation.

Recent progress of graphitic carbon nitride films and their application in photoelectrochemical water splitting

This review summarizes the progress in the synthesis of CN electrodes spanning from top-down and bottom-up categories, carrier dynamics modulation, and surface water oxidation reaction kinetics.

Plasma- assisted liquid-based growth of g-C3N4/Mn2O3 p-n heterojunction with tunable valence band for photoelectrochemical application

The practical application of graphitic carbon nitride (g-C3N4, CN) is restricted by its low photocatalytic activity and difficult recycling. Herein, we report a CN/Mn2O3 p-n heterojunction grown by a plasma-assisted liquid-based method using a special precursor complex of melamine-cyanuric acid supramolecular on fluorine-doped tin oxide (FTO) substrate. The as-grown CN/Mn2O3/FTO p-n heterojunction exhibits a significantly enhanced photoelectrochemical performance with a photocurrent density of 25 μA/cm2 compared with its powder form (0.9 μA/cm2) formed by common drop coating method，and a tunable valence band (VB) with excellent mechanical strength which is benefit for photocatalytic oxidation reaction and recovery. The formation of CN/Mn2O3/FTO p-n heterojunction can promote the transfer of photoelectrons due to an internal electric field at the interface of p-n junction, leading to the accumulation of electrons and holes in the VB of CN and conduction band (CB) of Mn2O3. The results have shed a light on promoting the practical application of CN, and the developed plasma-assisted liquid-based growth method can be extended to the preparation of other type of functional heterojunctions.

Construction of V-doped graphitic carbon nitride with nanotube structure for sustainable photodegradation of tetracycline

Low charge separation rate and limited light harvesting ability are the main obstacles for practical applications of graphitic carbon nitride (g-C3N4). Hence, a V doped hollow-nanotube g-C3N4 photocatalysts were prepared by electrospinning, chemical vapor deposition and impregnation pyrolysis method. The photocatalysts exhibited enhanced activity in degrading TC under visible light illumination (λ ≥ 420 nm) than pristine g-C3N4. The 7V-g-C3N4 showed the highest photocatalytic performance, and the reaction rate constant was 0.0071 min−1, which was 3.7 times that of g-C3N4, which could be attributed to the reduce of the recombination of photogenerated electrons and the narrow bandgap. Moreover, the enhanced photocatalytic performance of the as-synthesized catalyst is inseparable from the structure of the catalyst itself. The tubular catalyst was equipped with sufficient active sites and short diffusion distance. This work provides a novel way to fabricate nano-photocatalyst and demonstrates the applicability of V-doped photocatalyst for the utilization of sunlight such as the degradation of organic pollutants.

Significantly reinforced and long serviceable acrylonitrile butadiene rubber/graphitic carbon nitride composites for future industrial applications

The application of graphitic carbon nitride (g-C3N4) as non-black reinforcing filler is very little-known part in rubber technology. In the present study, g-C3N4 filled acrylonitrile butadiene rubber (NBR) composites were prepared by conventional two-roll milling process to investigate the influence of g-C3N4 on the mechanical and thermal performances of NBR formulations. NBR composite with 3 phr (parts per hundred parts of rubber) g-C3N4 presents considerably higher cure rate index, hardness, tensile strength, storage modulus and thermal stability than unfilled NBR composite. Also, the addition of g-C3N4 successfully enhances the thermal oxidative aging resistance and fuel consumption efficiency of NBR composites. Thus, g-C3N4 can be used in the near future as interesting filler for developing long serviceable NBR composites with good mechanical properties.

Computational and theoretical study of graphitic carbon nitride (g-C3N4) as a drug delivery carrier for lonidamine drug to treat cancer

The present study is designed to explore the potential application of graphitic carbon nitride (g-C3N4) for an anti-cancer Lonidamine drug-delivery by using DFT B3LYP/6-31G** level of theory. We have investigated the efficacy of g-C3N4 molecule as a carrier by calculating electronic, geometric, and excited-state properties of g-C3N4, lonidamine drug (LND), and g-C3N4-Lonidamine (g-C3N4-LND complex). The adsorption energy of g-C3N4-LND is about −0.40 eV. The adsorption energy value suggested the stability of g-C3N4-LND complex. The increased value of dipole moment for complex system is relatively useful for the solubility of the complex. After complex-formation, this rise in hydrophilicity in living systems proves to be beneficial for drug transfer. Through non-covalent interaction-analysis (NCI analysis), the nature of interaction among g-C3N4 and Lonidamine in the g-C3N4-LND was studied. The results of NCI analysis suggested that weak interaction-forces exist in the g-C3N4-LND complex. At the target site, these weak interactions are helpful for an easy off-loading of the LND from the g-C3N4. Furthermore, HOMO-LUMO analysis shows that during HOMO-LUMO excitation, the process of charge-transfer occurs from lonidamine to g-C3N4. For the g-C3N4-LND complex, excited-state calculations show that λmax showed blue-shift of 25 nm in the gas, and in the solvent (water) this λmax was blue shifted by 4 nm. Interestingly, theoretically calculated spectra are close to experimental spectra. Based on electron-hole theory, the photoinduced electron transfer (PET) process is explored for the first-five excited states. Moreover, g-C3N4 with both anionic (−1) and cationic (+1) states forms stable complexes with lonidamine drug and shows negligible changes in structures. Overall, it is stated that the g-C3N4 possesses a significant potential to be used as a vehicle for lonidamine drug delivery in cancer treatment. This research will also provide a channel for further investigation of other 2D (two-dimensional) materials in the field of drug delivery.

Synthesis, structure, and selected photocatalytic applications of graphitic carbon nitride: a review

Synthesis, structure, and selected photocatalytic applications of graphitic carbon nitride: a review

Bio-Derived Lithium-Ion Battery Anode Material for Fast Charging and Long-Cycle Life

Currently graphite is the most commercially used anode material for lithium-ion batteries (LIB), however its limited theoretical capacity of 372 mAhg-1 and slow kinetics cannot satisfy the requirements for EVs. Hence, alternative high energy density anode materials with fast kinetics are the need of the hour. The most recent development involves Mitsubishi Outlander PHEV which takes around 40 minutes for empty to full charging. Extreme fast charging, with a goal of 15 minutes fast charging, is poised to accelerate mass market production of electric vehicles. Extensive research is now directed towards carbonaceous materials that can fulfill the requirements for EV application. Key strategies involved in improving the rate capability of carbonaceous materials are (a) heteroatom doping, especially nitrogen doping and (b) increasing the d-spacing for accessing more active sites. Using conventional methods of heteroatom doping like pyrolysis of graphene oxide with urea or melamine as nitrogen source led to inclusion of up to 12 at% of nitrogen in general. Inclusion of nitrogen showed improvement in rate capability and capacity. Further search to increase nitrogen content led to the application of graphitic carbon nitride with nearly 55 at% nitrogen. Nevertheless, due to less electronic conductivity and change of crystallinity upon lithiation curbed its application in lithium-ion battery. So, currently our objective is to use nitrogen rich polymer as a single source of nitrogen and carbon to prepare heavily nitrogen doped carbon with nearly 20 at% of nitrogen with increased d-spacing and understand its effect on Li ion storage. Poly (2, 5-benzimidazole) (PBI) was synthesized by homo-polycondensation method using a bio derivable starting material 3, 4-diaminobenzoic, as earlier reported by Kaneko et.al1. The as prepared PBI was ground into fine powder before pyrolyzing at 800 ℃ in nitrogen atmosphere. Obtained carbon material was washed with HCl and water repeatedly and dried at 80 ℃ under vacuum before grinding into fine powder using mortar and pestle. Obtained material was systematically characterized before preparation of anodes for Li ion battery application. The SEM-EDX data revealed the content of nitrogen was as high as 18 at%. Using XPS studies, different types of nitrogen moieties were identified. Deconvolution of N1s peak revealed the presence of nitrogen in four different forms, graphitic nitrogen (10.3%), pyridinic nitrogen (6%), pyrrolic nitrogen (0.6%) and oxidized nitrogen (0.6%). The presence of pyridinic and graphitic nitrogen improve the electrical conductivity. The presence of high pyridinic nitrogen results in improved electrochemical activity. The contribution of pyridinic nitrogen in lithium storage is known to be maximum. XRD technique was utilized to understand the d-spacing of the material. Reflection corresponding to C (002) was used to calculate d-spacing. The results revealed that the d-spacing was found to be 3.5 Å which is nearly 0.2 Å higher than conventional graphite. The increased d-spacing can promote in faster diffusion of Li ion during intercalation and de-intercalation. TEM micrographs revealed the presence of macropores and mesopores. Using Cyclic Voltammograms at different scan rates and Randles Sevcik equation, the diffusion coefficient was calculated. Diffusion coefficient of PY PBI 800 was found to be several times higher than the conventional graphite anode, attributed to the increased d-spacing along with porous nature. Upon galvanostatic charge-discharge studies at different current rates, anode showed reversible capacity with nearly 99% coulombic efficiency upto 5C (1.8 Ag-1) rate. Further, long cycling studies were performed for >1000 cycles at 0.4, 0.8 and 1.8Ag-1 rates. Results indicated that PY PBI 800 can deliver highest de-lithiation capacity of ̴ 260 mAhg-1 at specific capacity of 0.4 Ag-1 rate (Fig) with nearly 88% capacity retention after 1000 cycles. At higher current rate of 0.8Ag-1, and 1.8 Ag-1 it showed highest discharge capacity of 165 mAhg-1 and 135 mAhg-1 with 90% and 75% capacity retention after 1000 cycles respectively. At 5C current rate, the battery can be charged and discharged in just 9 mins. Further, full cell was studied with LiCoO2 as cathode and PY PBI 800 as anode. Full cell studies also revealed the promising nature of PY PBI 800. Thus, carbonization is found to be a single method to enable high N-doping and increased d-spacing. The battery’s performance of charge discharge in just 9 min at 5C, with good capacity retention of nearly 75% after 1000 cycles demonstrated its promising potential for EV application.

Recent Advances in Graphitic Carbon Nitride Supported Single‐Atom Catalysts for Energy Conversion

AbstractSingle‐atom catalysts are one of the most energetic frontier research fields of catalysis, which exhibit distinctive performance for diverse chemical reactions due to the unique coordination environment, high atomic utilization, high activity and selectivity. Nevertheless, the size decrease of catalyst particles is accompanied with the sharply increased surface energy, thus ultra‐small particles are easy to form aggregation of nanoclusters and cannot maintain the atomic level dispersion. The key factor to protect catalytic sites is to regulate and control the interaction between single atoms and the substrate. As one of the most promising two‐dimensional supports to stabilize the isolated metal atoms, graphitic carbon nitride has been widely studied owing to the existence of abundant pyridine‐like nitrogen atoms for strongly anchoring metal centers and the distinct structure originating from electron rearrangement caused by the interaction between carbon and neighbor nitrogen atoms. In this review, we systematically generalize the controllable syntheses, theoretical calculations, characterizations and applications of graphitic carbon nitride supported isolated single‐atom catalysts, and finally, the prospects and challenges in this emergent field are featured on the basis of current experimental and computational efforts.

Controllable synthesis of Eu3+‐doped Y2O3 nanocrystal/g‐C3N4 composites with tunable fluorescence

ABSTRACTThe application of graphitic carbon nitride (g‐C3N4) has been restricted in some optoelectronics fields due to its narrow tunable emission region. In order to engineer the optical properties, herein we combine Eu3+:Y2O3 nanocrystals with g‐C3N4to control its electronic structure. Surprisingly, with the increasing concentration of Eu3+:Y2O3 nanocrystals, the photoluminescence of Eu3+:Y2O3/g‐C3N4 (EYCN) showed a continuous red shift in comparison with pure g‐C3N4 from blue to green. In EYCN composites, the Eu3+:Y2O3 nanocrystals as electron donors, can improve the degree of electron delocalization and narrow the bandgap. Importantly, the EYCN composites not only maintain the intrinsic blue‐green emission of g‐C3N4, but also introduce the red light of Eu3+ ions. Based on the EYCN composites, white light‐emitting diode (WLED) were fabricated with a Commission International de L’Eclairage value of (0.3631, 0.3560). This work proposes a new kind of luminescent g‐C3N4‐based composites, which is expected to broaden its applications in optoelectronics field.

CaH2-assisted structural engineering of porous defective graphitic carbon nitride (g-C3N4) for enhanced photocatalytic hydrogen evolution

The practical applications of graphitic carbon nitride (g-C3N4) for photocatalytic hydrogen evolution is strictly hindered by the low surface area, poor light harvesting capability and detrimental recombination of photoexcited charge carriers. Herein, using melamine as precursor and metal hydride (i.e., CaH2) as active agent, we facilely incorporate various types of defects (i.e., nitrogen (N) vacancies (VN), cyano groups (CN) and surface absorbed oxygen species(Oabs)) into g-C3N4 within a single step. The as-prepared material (denoted as MM-H) exhibits narrowed bandgap, promoted photoexcited electron-hole separation rate and facilitated charge transfer kinetics with enlarged BET surface area and massive porosity. As a result, a prominently enhanced photocatalytic H2 productivity efficiency (1305.9 μmol h−1g−1) is shown on MM-H. This performance is better than that of g-C3N4 with CaH2 post-treatment (617.3 μmol h−1g−1) and raw bulk-C3N4 (178.2 μmol h−1g−1). This work opens up a new dimension for designing high performance g–C3N4–based catalysts targeting various photocatalytic processes.