3N4 Nanocomposites Research Articles

Construction of Z-scheme SbVO4/g-C3N4 heterojunction with efficient photocatalytic degradation performance

As visible light responsive materials, g-C3N4 has become an outstanding research object for photocatalysis due to its facile synthesis, excellent chemical and thermal stability. In this paper, a Z-scheme SbVO4/g-C3N4 heterojunction was successfully constructed by thermal polymerization method. The synthesized SbVO4/g-C3N4 nanocomposite showed efficient photocatalytic activity on tetracycline (TC) degradation. The photocatalytic degradation of TC follows a first-order kinetic model, in which ·O2− and ·OH free radicals play a major role. The formation of Z-scheme heterojunction between SbVO4 and g-C3N4 can effectively promote the separation of photogenerated electron-hole pairs and the generation of ·O2− and ·OH. The photocatalytic removal rate of TC reached 82.3 % within 150 min under visible light. The as-synthesized SbVO4/g-C3N4 heterojunction can still maintain good stability. Furthermore, a photocatalytic degradation mechanism for the SbVO4/g-C3N4 heterojunction is proposed.

Evaluate the Ni-ZnO/g-C3N4 Nanocomposite for Photocatalytic Degradation of Organic Defect Degradation and Antibacterial Activity

Evaluate the Ni-ZnO/g-C3N4 Nanocomposite for Photocatalytic Degradation of Organic Defect Degradation and Antibacterial Activity

FeCo-LDH/g-C3N4 S-scheme photocatalyst with visible light response and enhanced photocatalytic performance

FeCo-LDH/g-C3N4 S-type heterojunction photocatalysts were successfully prepared by thermal polymerization and electrostatic self-assembly methods. The structure, morphology, light absorption and photoelectrochemical properties of the prepared samples were characterized. The photocatalytic properties of the photocatalysts were evaluated by the degradation of tetracycline (TC) and photocatalytic hydrogen evolution from water splitting under visible light irradiation. The experimental results showed that the photocatalytic properties of FeCo-LDH/g-C3N4 nanocomposites were superior to those of pristine g-C3N4. In addition, when the mass ratio of FeCo-LDH to g-C3N4 was 7:100, the photocatalytic performance of the as-prepared FeCo-LDH(7 %)/g-C3N4 is the optimal. The TC degradation rate of FeCo-LDH(7 %)/g-C3N4 reached 78.0 % within 120 min, which was 2.63 times of that of pure g-C3N4. And the photocatalytic hydrogen evolution of FeCo-LDH(7 %)/g-C3N4 was 107.28 μmol for 4 h, which was 12.68 times that of g-C3N4. The results showed that the as-prepared FeCo-LDH/g-C3N4 nanocomposite photocatalysts have excellent performance in the degradation of TC and the photocatalytic H2 evolution. Meanwhile, the EPR and trapping experiments revealed that OH and O2− played a main role in the photocatalytic TC degradation. The mechanism of photocatalytic TC degradation and hydrogen production of FeCo-LDH/g-C3N4 nanocomposite photocatalysts was also discussed.

Constructing multifunctional novel noble-metal free NiS/ZnS/g-C3N4 ternary nanocomposites for highly active superior photocatalytic water splitting

Ultrasound-assisted wet-impregnation approach and cation-exchange hydrothermal method are employed effectively to develop the ternary nanocomposites NiS/ZnS/g-C3N4 (NZ-CN) with promising photocatalytic hydrogen (H2) generation activity. Several analytical techniques are utilized to characterize the as-synthesized NiS/ZnS/g-C3N4 nanocomposites to study their physical and chemical characteristics. The H2 production activity of the synthesized photocatalysts was tested using a 250 W halogen lamp with Na2S (0.25 M) and Na2SO3 (0.35 M) as sacrificial reagents. The optimized NZ-CN7.5% (3% NiS/ZnS/7.5% g-C3N4) catalyst displayed an exceptional H₂ generation rate of 8624 μmol h⁻1 g⁻1, exceeding both, pristine g-C3N4 (by 22.1 times) and 3% NiS/ZnS (by 3 times). This represents the highest reported rate of H₂ evolution for a graphitic carbon nitride (g-C3N4) based ternary nanocomposite under simulated solar radiation. By reusing the used NZ-CN7.5% (3% NiS/ZnS/7.5% g-C3N4) photocatalyst in four consecutive runs, the stability of the catalyst was investigated, and their individual activity in the H2 production activity was assessed. This study provides valuable insights for designing efficient noble metal-free g–C3N4–based photocatalysts, which can significantly contribute to the transition to solar-driven hydrogen generation. Further, we proposed a plausible mechanism for the photocatalytic H2 generation process over the NiS/ZnS/g-C3N4 photocatalyst.

Auto-combustion synthesis and characterization of La2CrMnO6/g-C3N4 nanocomposites in the presence trimesic acid as organic fuel with enhanced photocatalytic activity towards removal of toxic contaminates

Constructing semiconductor materials based on layered graphitic carbon nitride (g-C3N4) and metal oxides can help in extending the lifetime of charge carriers and aid in resolving the low number of active sites on their surface for light-driven processes. Herein, we initially designed La2CrMnO6 nanostructures through trimesic acid-assisted auto-combustion route and subsequently, La2CrMnO6/g-C3N4 nanocomposites were prepared by ultrasonic-assisted co-precipitation method with improved UV-catalytic performance. The shape, size distribution and various properties of nano-sized products were measured via diverse description systems of microscopic and spectroscopic. The photocatalytic performances of the La2CrMnO6 nanoparticles and La2CrMnO6/g-C3N4 nanocomposites were compared by degradation of artificial dyes under the UV-light region. Besides, the impacts of dye type, diverse weight percentages of g-C3N4:La2CrMnO6 in composite, scavenger kind and dye solution concentration were studied on modifying ability of nano-catalyst utility. The outcomes manifested La2CrMnO6/g-C3N4 (80:20) nanocomposites have the greatest efficiency, where the highest MO decomposition of 80.98 % was achieved at 10 ppm within 90 min of irradiation. Moreover, the feasible mechanism of MO elimination by UV catalytic purpose was considered.

Enhancement in Sensitivity and Selectivity of Electrochemical Technique with CuO/g-C3N4 Nanocomposite Combined with Molecularly Imprinted Polymer for Melamine Detection.

This study focused on enhancing the sensitivity and selectivity to detect melamine by utilizing a photoelectrochemical method. This was achieved by combining a melamine-imprinted polymer with a CuO/g-C3N4 nanocomposite, which was synthesized through chemical precipitation and calcination. The resulting nanocomposite exhibits improved carrier mobility and photoelectrochemical properties. A molecularly imprinted receptor for selective detection was created through bulk polymerization with methacrylic acid and a melamine template. The characterization of the nanocomposite was performed using X-ray photoelectron spectroscopy for the chemical oxidation state, X-ray diffraction patterns for the crystalline structure, and ultraviolet/visible/near-infrared spectroscopy for optical properties. The CuO/g-C3N4 nanocomposite exhibits photoactivity under visible light. The modified electrode, incorporating the CuO/g-C3N4 nanocomposite and melamine-imprinted polymer, demonstrates a linear detection range of 2.5 to 50 nM, a sensitivity of 4.172 nA/nM for melamine, and a low detection limit of 0.42 nM. It shows good reproducibility and high selectivity to melamine, proving effective against interferences and real samples, showcasing the benefits of the molecularly imprinted polymer.

Synthesis and characterization of (Ni, Mn)-ZnO/g-C3N4 nanocomposite for efficient electrochemical water splitting: The role of electrocatalyst for OER

The scarcity of non-renewable energy sources and rising worldwide temperatures are significant challenges. Electrochemical water splitting using low-cost materials (metals and their oxides) is a highly efficient and cost-effective method of producing both hydrogen and oxygen. Apart from precious metals, carbon-based materials have also shown effectiveness in catalyzing these reactions. To minimize overpotentials and enable practical applications, metal oxide encapsulation in graphite layers has demonstrated significant activity for both HER and OER. Metal oxides are known for their high conductivity and mechanical strength, making them suitable candidates for this task. In the present research, we report the design of a composite (Ni, Mn)-ZnO/g-C3N4 ((Ni, Mn)-CNZ) electrocatalyst with improved electrocatalytic performance. The coprecipitation of (Ni, Mn)-ZnO with graphitic carbon nitride (g-C3N4) produced the composite material. The structure of the electrocatalyst was analyzed using characteristic techniques such as FTIR, EDX, SEM, and XRD. Electrodeposition on FTO glass is employed to facilitate studies of water distribution. The (Ni, Mn)-CNZ composite exhibits excellent electrochemical water-splitting behavior, with low overpotentials, 380 mV (OER) and 288 mV (HER), reaching a current density of 10 mA cm−2 compared to Ni-CNZ and Mn-CNZ. This highlights the potential of (Ni, Mn)-CNZ as a highly effective electrocatalyst for water splitting.

Photodegrading rhodamine B dye with cobalt ferrite-graphitic carbon nitride (CoFe2O4/g-C3N4) composite

The present research utilizes a sol-gel approach to create a CoFe2O4/g-C3N4 nanocomposite (NC) and explored several analytical methods to evaluate physical, chemical and optical based characteristics via XRD, FTIR, UV–vis, SEM/EDS and XPS for the prepared pure CoFe2O4, g-C3N4, and CoFe2O4/g-C3N4 NC. The XRD results show that the prepared g-C3N4, CoFe2O4, exhibits hexagonal and cubic phases respectively, whereas the g-C3N4/CoFe2O4 NC exhibit mixing of two phases. The energy band gaps for pure g-C3N4, CoFe2O4 and g-C3N4/CoFe2O4 NC values are viz., 2.75, 1.3, and 2.4 eV. As photocatalysts, synthesized materials were utilized for the decomposition of Rhodamine-B (RhB) dye. Finally, the CoFe2O4/g-C3N4 NC showed good performance of photocatalysis for RhB dye disintegration under the stimulus of visible light. According to the induced visible light, the rate at which the photocatalytic degradation occurs for the CoFe2O4/g-C3N4 NC was found to be 57% in 120 min and this is greater when compared with pure catalysts like CoFe2O4 (28%) and g-C3N4 (10%). These outcomes suggest that the prepared NC have efficiently worked during the photocatalytic process compared with its pure materials.

BPGQD/g-C3N4 nanocomposites as sensitive and selective platform for fluorescence and RGB based detection of vitamin B12

Here, a brand-new fluorescence BPGQD/g-C3N4 nanocomposite for measuring Vitamin B12 has been created. The technique is based on the interaction between Vitamin B12 and graphitic nitride nanosheets modified with graphene quantum dots co-doped with boron and phosphorus. The developed nanocomposites have been characterized by using various techniques such as HR-TEM, SEM, EDS, XRD, FT-IR, XPS, Photoluminescence and UV–Vis absorption spectroscopy. Different excitation wavelengths were used, with a 320 nm excitation wavelength and a 416 nm emission wavelength chosen for fluorometric detection. It examined how several factors, including the sample solution's pH, the length of the incubation period, and the impact of NaCl concentration, affected the intensity of the fluorescence. A linear standardization curve was validated in the Vitamin B12 range of 0–60 nM under the authorized conditions. The limit of detection (LOD) and limit of quantitation (LOQ) were 9.61 nM and 29.12 nM respectively. Using newly created nanocomposites, an RGB-based sensor for Vitamin B12 detection was also constructed. Using this probe, it was possible to determine the amount of Vitamin B12 in human urine samples with respectable outcomes and satisfactory recoveries.

Selective photochemical oxidation of sulfides by Gallium and Sulfur Co-Modified TiO2/g-C3N4 Nanocomposites as catalyst

In this study, with the objective of promoting the oxidation of sulfides, a distinctive photocatalyst was synthesized by incorporating Ga- and S-co-doped TiO2 onto graphitic carbon nitride (g-C3N4). Under visible light irradiation, the composites demonstrated enhanced photocatalytic performance in comparison to g-C3N4 and TiO2/g-C3N4. The nanocomposite catalyst displayed a remarkable enhancement in photocatalytic activity, benefiting from the creation of a Z-scheme heterojunction by combining TiO2 and g-C3N4, as well as the presence of electron trap centers, efficient photogenerated electron transfer, improved charge carrier separation, and extended optical absorption in the visible light range. To optimize the performance, the substitution contents of Ga and S (GaxSy@TiO2-g-C3N4) were varied, where the values of x and y were set at 5 % and 10 %, respectively. Notably, Based on the obtained results, it was observed that the Ga5.0S10.0@TiO2-g-C3N4 sample displayed the highest yield when subjected to visible-light irradiation, making it the most effective and optimal sample. The findings of this study offer a fresh perspective on the synergistic effect of dopant photocatalysts in the oxidation of organic compounds. This work presents a novel approach for the development of highly efficient photocatalysts capable of effectively oxidizing organic compounds.

Design and fabrication of graphitic carbon nitride incorporated zinc silicate hybrid nanocomposite for effective degradation of eriochrome black T dye as water pollutant under sunlight irradiations

This paper presents an approach to prepare zinc silicate (Zn2SiO4) and its nanocomposites with graphitic carbon nitride (g-C3N4) for enhanced photocatalytic performance. Zn2SiO4 was synthesized using a simple and cost-effective sonochemical method, followed by the fabrication of Zn2SiO4/g-C3N4 through an ultrasonic-assisted co-precipitation method. The characterization of Zn2SiO4 and its nanocomposites was carried out using various techniques such as XRD, FTIR, EDS, SEM, TEM, BET, and DRS. The main focus of this study was to investigate the photocatalytic efficiency of g-C3N4, Zn2SiO4, and different Zn2SiO4 nanocomposites for the degradation of eriochrome black T (EBT) and erythrosine (ER). It is worth noting that this is the first time Zn2SiO4 has been combined with carbon nitride, which resulted in excellent photocatalytic performance. The experimental results revealed that several factors influenced the efficiency of the photocatalytic process, including the content of Zn2SiO4 in the nanocomposite, catalyst loading, and initial concentration of EBT. Among all the tested compositions, Zn2SiO4/g-C3N4 with 10 % Zn2SiO4 exhibited the best performance. Specifically, when 70 mg of 10 % Zn2SiO4/g-C3N4 was used as a catalyst, it achieved a remarkable degradation efficiency of 75.5 % for 10 ppm EBT. This finding highlights the potential application of Zn2SiO4/g-C3N4 nanocomposites as efficient photocatalysts for environmental remediation. The results of scavenger test indicated that superoxide radicals and positive holes played significant roles in driving the photodegradation reactions. Furthermore, a kinetics study was performed to determine the rate constant (k) associated with the photocatalytic process. It was observed that a higher rate constant (k = 0.011 min−1) corresponded to a higher efficiency of 75.5 %. This finding suggests that the Zn2SiO4/g-C3N4 nanocomposites possess excellent photocatalytic activity and can effectively degrade organic pollutants.

Fabrication and photocatalytic evaluation of Cr-doped-ZnO/S-g-C3N4 nanocomposite: exploiting the synergistic effect for efficient environmental remediation

Fabrication and photocatalytic evaluation of Cr-doped-ZnO/S-g-C3N4 nanocomposite: exploiting the synergistic effect for efficient environmental remediation

Zinc hexacyanoferrate/g-C3N4 nanocomposites with enhanced photothermal and photodynamic properties for rapid sterilization and wound healing

Photoactivated therapy has gradually emerged as a promising and rapid method for combating bacteria, aimed at overcoming the emergence of drug-resistant strains resulting from the inappropriate use of antibiotics and the subsequent health risks. In this work, we report the facile fabrication of Zn3[Fe(CN)6]/g-C3N4 nanocomposites (denoted as ZHF/g-C3N4) through the in-situ loading of zinc hexacyanoferrate nanospheres onto two-dimensional g-C3N4 sheets using a simple metal-organic frameworks construction method. The ZHF/g-C3N4 nanocomposite exhibits enhanced antibacterial activity through the synergistic combination of the excellent photothermal properties of ZHF and the photodynamic capabilities of g-C3N4. Under dual-light irradiation (420 nm + 808 nm NIR), the nanocomposites achieve remarkable bactericidal efficacy, eliminating 99.98% of Escherichia coli and 99.87% of Staphylococcus aureus within 10 minutes. Furthermore, in vivo animal experiments have demonstrated the outstanding capacity of the composite in promoting infected wound healing, achieving a remarkable wound closure rate of 99.22% after a 10-day treatment period. This study emphasizes the potential of the ZHF/g-C3N4 nanocomposite in effective antimicrobial applications, expanding the scope of synergistic photothermal/photodynamic therapy strategies.

Crafting high-performance CuZnO2/g-C3N4 nanocomposites: unleashing the power of dual-functional photocatalysis and antibacterial action

Crafting high-performance CuZnO2/g-C3N4 nanocomposites: unleashing the power of dual-functional photocatalysis and antibacterial action

Preparation of nanosheet g-C3N4 coupled with Polycalix [4] resorcinarene: Survey characterization and photocatalytic activity for the degradation of 4-Nitrophenol

Here, we have synthesized Polycalix[4]resorcinarene (PC4RA) covalently coupled with carbon-modified porous graphitic carbon nitride (g-C3N4). The nanocomposites were characterized by (FTIR), (XRD), (SEM), Transmission (TEM), and DRS–UV–Vis spectroscopic methods. Photocatalytic activities of the PC4RA/g-C3N4 nanocomposites with different ratios of g-C3N4 were evaluated for degradation of 4-Nitrophenol under visible light irradiation under light irradiation of λ ≥ 320 nm. Three parameters were applied including the initial concentration of 4-nitrophenol, the amount of photocatalyst, and irradiation time. and the results of the photocatalytic performance suggest that the catalytic activity is strongly influenced by the presence of the g-C3N4 content. Especially the nanocomposite’s photocatalytic efficiency was the highest (98.32 % after 120 min) when the ratio of g-C3N4 was (1/2). However, an increase of the photocatalytic activities was related to the interfacial transfer of photogenerated electrons and holes, leading to the effective charge separation. The durability and stability of the nanocomposites have been examined and can endure the experimental conditions even after eight successive cycles. This approach opens up an avenue for the fabrication of graphitic carbon nitrite-based metal-free heterogeneous nanocomposites with high catalytic performance.

A two-symmetric electrode hydride supercapacitor developed from G-C3N4 decorated with poly-2-aminobenzenethiol

The incorporation of poly-2-aminobenzene thiol (P2ABT) onto 2D g-C3N4 sheets results in the formation of a P2ABT/g-C3N4 nanocomposite, exhibiting favorable morphological and electrical properties that position it as a promising candidate for a paste utilized in a two-symmetric electrode hydride supercapacitor. The decoration process involves the oxidation of 2-aminobenzene thiol with K2S2O8, leading to the polymer coating of the embedded 2D g-C3N4 materials, yielding a robust composite. Analysis via scanning electron microscopy (SEM) unveils the formation of 2D sheets of g-C3N4 with an average length, width, and thickness of 750 nm, 200 nm, and 15 nm, correspondingly. The composite establishes a sturdy network with a porous structure, indicative of the synergistic combination of the electrical characteristics of the polymer and g-C3N4. In the construction of the two-symmetric electrode supercapacitor, an impressive specific capacitance (CS) of 310 F g−1 is achieved at 0.2 A/g. The supercapacitor exhibits a promising energy density (E) of 26.8 W h kg−1 and maintains retention stability even after undergoing 1000 charge/discharge cycles. Notably, the retention rate remains high at 98% after 250 cycles and 96% after an extended cycling period of 1000 cycles. This exceptional performance positions the supercapacitor as a prospective candidate for applications in industrial settings and within batteries. Its advantages lie in its ease of fabrication, mass production capabilities, and cost-effective manufacturing techniques, opening new avenues for these materials in energy storage fields.

Interface engineered cascade-type electronic structure of 2D/0D/2D CdS–CdCO3/SnO2 quantum dots/g-C3N4 nanocomposite for boosting solar-driven photocatalysis

A rational design of heterojunctions with high-quality contacts is essential for efficiently separating photogenerated charge carries and boosting the solar-driven harvesting capability. Herein, we fabricated a novel heterojunction of SnO2 quantum dots–anchored CdS–CdCO3 with g-C3N4 nanosheets as a superior photocatalyst. SnO2 quantum dots (SQDs) with positively charged surfaces were tightly anchored on the negatively charged surface of CdS nanosheets (NSs). The resulting CdS@SnO2 was finally decorated with g-C3N4 NSs, and a new crystalline phase of CdS–CdCO3 was formed during the hydrothermal decoration process, g-C3N4 decorated CdS–CdCO3@SnO2 (CdS–CdCO3@SnO2@g-C3N4). The as-synthesized photocatalysts were evaluated for the degradation of methyl orange dye under solar light conditions. The CdS–CdCO3@SnO2@g-C3N4 exhibited 7.7-fold and 2.3-fold enhancements in photocatalytic activities in comparison to those of the bare CdS and CdS@SnO2 NSs, respectively. The optimal performance of CdS–CdCO3@SnO2@g-C3N4 is primarily attributed to the cascade-type conduction band alignments between 2D/0D/2D heterojunctions, which can harvest maximum solar light and effectively separate photoexcited charge carriers. This work provides a new inspiration for the rational design of 2D/0D/2D heterojunction photocatalyst for green energy generation and environmental remediation applications.

Recyclable Au@R–Fe3O4/g-C3N4 substrates for rapid SERS detection and degradation of multiple pollutants

Developing a Surface-enhanced Raman spectroscopy (SERS) method with excellent detecting ability, good recyclability and analyzing multiple pollutants rapidly are critical for evaluation of water quality in emergency pollution affairs. While constructing a multifunctional substrate with these characteristics to realize the application of SERS in water quality monitoring remains a challenge. In this work, a reusable Au@R–Fe3O4/g-C3N4 SERS substrate is prepared by loading Au nanoparticles (Au NPs) on Fe3O4 nanorings (R–Fe3O4) and the formed Au@R–Fe3O4 is further combined with g-C3N4 nanosheets through a simple electrostatic assembly method. The Au@R–Fe3O4/g-C3N4 nanocomposite presents multifunction of magnetic enrichment, SERS signal enhancement, multiple pollutants analyzing, and photocatalytic activity, which achieves quantitative detection of rhodamine B (RhB), tetracycline hydrochloride (TC), and 4-chlorophenol (4-CP), with detection limits of 5.30 × 10−9, 7.50 × 10−8, 7.69 × 10−8 mol/L, respectively. Furthermore, the recyclable detection capability of Au@R–Fe3O4/g-C3N4 for multi components is demonstrated by the strong SERS signal after 9 cycles of “detection-degradation” processes. Combined with good uniformity and stability, this SERS method based on Au@R–Fe3O4/g-C3N4 substrate provides a new strategy for the multi-pollutants detection and degradation in water environment.

Revolutionising pesticide detection: a high-sensitivity electrochemical sensor with CdS/g-C3N4/MWCNTs for paraquat monitoring

ABSTRACT Over a decade, the Malaysia National Poison Centre found that 40% of pesticide poisoning cases may be linked to excessive paraquat (PQ) in water, soil, or food, underscoring the widespread impact on public health and emphasising the importance of detecting even trace amounts of PQ residues in the environment. Thus, this study presents a novel electrochemical sensor based on multiwalled carbon nanotubes (MWCNTs) reinforced cadmium sulphide co-anchoring on graphitic carbon nitride (CdS/g-C3N4) nanocomposites for PQ detection. The CdS/g-C3N4 nanocomposite was successfully synthesised and characterised through FTIR, XRD, EDX, FESEM and TEM analysis. The modified electrode (CdS/g-C3N4/MWCNTs PE) exhibited improved electrocatalytic activity, as demonstrated by cyclic voltammetry (CV) and impedance spectroscopy. The CdS/g-C3N4/MWCNTs PE displayed a high CV peak and low Rct value which corresponded to a higher electron transfer rate, reduced charge transfer resistance and enhanced mass transport properties. The electrochemical sensor’s performance was evaluated for the detection of PQ, and it demonstrated a linear response in a range of 1.0 µM to 0.1 mM with a limit of detection of 0.14 μM. Furthermore, the sensor exhibited selectivity with a less than 16% potential interference from various organic chemicals and inorganic ions. The sensor’s applicability was tested by quantifying PQ in real water samples, showing excellent recovery percentages ranging from 98.9% to 102.0%. The developed electrochemical sensor provides a practical solution for the rapid and accurate monitoring of PQ levels in the environment. This work establishes the foundation for the development of a selective electrochemical sensor for pesticide analysis, addressing both public health and environmental concerns.

Earthworm excrete derived-enzyme enriched SnO2/g-C3N4 nanocomposite for near complete decomposition of toxic dye molecules

Enzymes derived from earthworm (Eudrilus eugeniae) excretes (vermiwash) were used as supporting bio-catalysts with SnO2/g-C3N4 nanocomposites for photocatalytic dye degradation of toxic organic dyes. The results were compared to those of the composite partners SnO2 and g-C3N4. The enzyme supported nanocomposite has superior photocatalytic efficiency of 95 %, 93 %, 83 % and 97 % against the test dyes Methylene Blue (MB), Malachite Green (MG), Methyl Orange (MO) and Rose Bengal (RB) whereas the partners SnO2 (62 %, 81 %, 36 % & 73 %) and g-C3N4 (76 %, 84 %, 80 % & 89 %) exhibited lower efficiencies. The enzymes phosphatase, amylase, urease and protease present in the synthesized nanocomposite play supporting role as co-catalyst in enhancing the photocatalytic ability of the nanocomposite. The mechanism involving the charge carrier recombination delay due to the formation of g-C3N4 sheets beneath the SnO2 particles is illustrated. The partnering mechanism with g-C3N4 having lower bandgap (2.8 eV) leads to a reduction in the bandgap from 3.5 eV for SnO2 to 2.6 eV for the nanocomposite making the nanocomposite as visible light responsive photocatalyst. The XRD, FTIR, SEM-EDX, UV–vis–NIR, XPS and DFT results support the discussion on photocatalytic mechanism. The near complete dye degradation is confirmed by phenotypic test on earthworm (Eudrilus eugeniae).