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Rubberwood biomass is widely available in the southern region of Thailand and it has high potential for biofuel applications. Applications of this biomass still have some limitations, however, such as low energy properties and high biological decomposition. Therefore, the aim of this study was to enhance the fuel properties of rubberwood biomass by a torrefaction process. Rubberwood sawdust (RWS) was torrefied at different temperatures (200, 250, and 300 °C) and for various times (20, 40, and 60 min) in a moving bed reactor. The product yield and characteristics of torrefied RWS were investigated. Results showed that the solid yield of torrefied RWS was in the range of 39.07–88.69%, depending on temperature and time. The fuel atomic ratios of torrefied RWS were better than of raw RWS. The energy content and energy density of torrefied RWS were clearly enhanced (19.78–27.17 MJ/kg and 4.94–6.59 GJ/m3). ICP-OES results revealed a variation of inorganic elements in torrefied RWS, which was consistent with the ash components given by XRF. Ash fusion temperature of raw RWS and torrefied RWS ashes was stable at 1458 °C. The slagging index of torrefied RWS was decreased, while its fouling index was elevated. [Display omitted] • Yield and properties of torrefied RWS were clearly influenced by temperature. • Fuel atomic ratios and energy properties of RWS were improved by torrefaction. • Fusion temperature of torrefied RWS ash was above 1458 °C. • Torrefaction increased fouling index of RWS but reduced its slagging index. [ABSTRACT FROM AUTHOR]

This study aimed to investigate the physicochemical changes and energy properties of torrefied rubberwood sawdust (RWS) produced in various sizes of moving bed reactors for further pelletization. The results indicate that the torrefaction of RWS with a small-scale reactor at higher temperatures led to a stronger degree of torrefaction (DT) based on various indicators. Torrefaction at 250 °C for 60 min provided appropriately torrefied RWS with solid yield, energy yield, energy content, and energy density of 70.23%, 81.20%, 22.20 MJ/kg, and 5.40 GJ/m3, respectively. The RWS with higher DT was coal-black instead of brown, as indicated by its L*, a* and b* color coordinates. The changes in color and DT were also consistent with the improvements in fuel ratio, atomic ratios, lignin content and functional groups (FTIR). SEM imaging and BET adsorption also confirmed the surface changes from raw RWS to torrefied RWS. At the same nominal conditions, torrefaction of RWS with a larger scale reactor gave a small difference in solid yield and in properties of the torrefied RWS. In addition, the production and energy costs are the key concerns in a large-scale operation. These results support pursuing further applications, like the pelletization of torrefied RWS. [Display omitted] [ABSTRACT FROM AUTHOR]

Abstract: The addition of natural antioxidants onto white rice kernel can improve its functionality. Curcuminoids that present in turmeric rhizomes possess high antioxidant activity and heat stability. The objective of this study was to investigate the effects of inlet air temperatures and spray rates of turmeric extract solution on quality attributes of the turmeric extract coated rice (TCR) using the top-spray fluidized bed coating technique. The experimental results have shown that inlet air temperature and spray rate of coating solution strongly affected the final moisture content and percentage of fissured kernel of TCR. Almost all of TCR kernels in the bed cracked when their final moisture content was lower than 11.8% wet basis. However, the head coated rice yield of fissured TCR slightly decreased from that of white rice. The color of TCR was uniform over the entire surface. Texture of cooked TCR insignificantly changed from that of uncoated sample. Increasing spray rate provided higher both total phenolic content (TPC) and total antioxidant capacity (TAC) whilst increasing inlet temperature yielded lower TPC but it did not affect TAC. Retentions of TPC and TAC of TCR after cooking remained higher than 90%. [Copyright &y& Elsevier]

This study demonstrates and quantifies biomethanation improvements from practical schemes of retrofitting anaerobic plug flow (PF) digester for piggery wastewater (1% total solids concentration). First, batch assays were performed to seek the optimal scenario for substrate solubilization. By regulating micro-aeration at different levels, results showed that ORP −420 ± 10 mV promoted maximal hydrolysis efficiency (η H), to as high as 49.5% above the control (without micro-aeration). However, organics were markedly lost by over oxidation beyond the optimal ORP. Sub-thermophilic (45 °C) was also proven as effective (p ≥ 0.05) as thermophilic (55 °C) temperature for hydrolysis with η H 89% higher than that of the ambient (mesophilic) temperature. In continuous digestion studies, the two-stage operations, achieved by adding a pre-hydrolysis (pHY) reactor (HRT 1 day) to the main PF reactor (HRT 4 days), were assessed under four retrofitting schemes. Results showed incremental improvements of each strategy applied and suggested the best overall system configuration of pHY 45 C − 420 mV + PF 45C with sludge re-hydrolysis. Methane yield was improved by 20.4% over the original PF digester operation. Next Generation Sequencing indicated significant changes in abundance and diversity of the major groups of organisms by the sub-thermophilic temperature that linked to the augmented biomethanation performance. Preliminary cost-benefit analysis is also presented. A full-scale implementation in a pilot farm in Thailand is under development. [Display omitted] • Advanced retrofitting schemes to piggery waste digestion were experimentally tested. • Pre-hydrolysis via micro-aeration is effectively controlled by redox potential. • Hydrolysis/acidogenic efficiency at 45 °C statistically equals to thermophilic 55 °C. • Sludge re-hydrolysis was proven the most effective scheme to enhance CH 4 yield. • Changes in microbial abundance and diversity at 45 °C are linked to CH 4 yield rise. [ABSTRACT FROM AUTHOR]

• Pyrolysis and co-pyrolysis of RWS and OPT by using moving bed reactor were studied. • Yield and characteristics of bio-oil, biochar and gas were determined and analyzed. • Bio-oil from RWS was better than those from OPT and RWS mixed with OPT. • Co-pyrolysis enhanced yield and quality of bio-oil, biochar and gas. • RWS and OPT are challenging feedstocks for pyrolysis and co-pyrolysis. This study investigated the yields and characteristics of bio-oil, biochar and pyrolysis gas obtained from pyrolysis and co-pyrolysis of rubber wood sawdust (RWS) and oil palm trunk (OPT) by using an agitated bed pyrolysis reactor. Co-pyrolysis of RWS and OPT was performed at the mixing ratio of 50:50 (wt.). The biomass samples were pyrolyzed at temperatures of 400, 450, and 500 °C under specific conditions. The results indicated that the yields of the bio-oil, biochar and pyrolysis gas were in the ranges of 38.5-46.5, 22.27-28.68 and 30.1-36.9 wt.%, respectively. Pyrolysis of RWS at 500 °C provided the most bio-oil. Co-pyrolysis of RWS and OPT could improve the product yield and quality. The bio-oil had relatively high water content, while its pH was low. The main compounds of bio-oil were oxygenated compounds such as acetic acid, phenols and 2-Propanone, 1-hydroxy-, determined by GC-MS. The higher heating value (HHV) of bio-oil ranged from 16.1 to 20.36 MJ/kg. The biochar had high carbon content and low oxygen content in proximate and ultimate analysis, and based on FTIR. The HHV of biochar was in the range from 26.35 to 29.6 MJ/kg. The biochar also was highly porous, which was revealed by SEM and BET. The pyrolysis gas mainly contained CO, CO 2 , H 2 and CH 4 , and its heating value was in the range from 3.23 to 6.7 MJ/m3. Based on these results, the RWS and OPT are alternative and challenging biomasses for conversion to biofuels and value-added products via pyrolysis. [ABSTRACT FROM AUTHOR]

Durian peel is a type of biomass derived from agricultural residues, which are found in abundant in Thailand. This study aims to investigate the thermal and chemical properties of three indigenous durian peels, namely Monthong (MDP), Puangmanee (PDP), and Bacho (BDP), as well as the characteristics of biochar and pyrolysis liquid derived from slow pyrolysis of the durian peel. MDP had the greatest volatile matter and fixed carbon content, with 73.97 and 18.43 wt%, respectively. MDP was applied for further research in order to produce biochar and pyrolysis liquid at pyrolysis temperatures of 400 and 600 °C. The maximum biochar yield was 36.01% at 400 °C, while the maximum pyrolysis liquid yield was 37.25% at 600 °C. The largest high heating value of biochar (24.48 MJ kg−1) was obtained at 600 °C more than the high heating value of feedstock (14.32 MJ kg−1). Biochar obtained at 400 °C can be categorized as fertilizer class 4, while biochar obtained at 600 °C can be classified as carbon storage class 2 using the IBI biochar classification tool. The quality of the pyrolysis liquid was determined to be of 3.14 pH and 1.052 g mL−1 specific gravity at a pyrolysis temperature of 600 °C, which meets Thailand standards. As a result, both 400 °C and 600 °C pyrolysis liquids produced significant chemicals that are employed in a variety of industries. Consequently, this research is strongly recommended to be expanded to produce high-quality durian peel biochar and pyrolysis liquid. [Display omitted] • Comprehensive physical, chemical, thermal properties of durian peels were explored. • Durian peel biochar can be categorized by the IBI as carbon storage class 2. • The biochar can be classified by the IBI as a high fertilizer class 4. • Pyrolysis liquid derived from the durian peel meet Thailand standards. • 81 main compounds with essential chemicals were detected in the pyrolysis liquids. [ABSTRACT FROM AUTHOR]

Graphical abstract for the production of value add biomass sources. [Display omitted] • Herein, we used dual catalyst by generating maximum yield of 44.058 wt.% of bio-oil and gas yield of 28.942 wt.% along with 27.00 wt.% of bio-char. While in thermal pyrolysis of lignin the bio-oil yield of 40.79 wt.% and gas yield of 29.7 wt.% along with 29.51 wt.% of bio-char is achieved. • The biomass product (gas and Bio-oil) was characterized using GC-FID and GC–MS. The dual catalyst bed showed a considerable effect on the bio-oil composition and oxygenates were reduced. • The bio-oil exhibit a high quantity of phenols and aromatic. In the gas product, the H 2 yield has been enhanced from 28.97 mL/g to 42.68 mL/g and CH 4 yield enhanced from 32.07 mL/g to 40.44 mL/g. In this study, we developed an effective method for converting lignin into useful compounds to replace fossil-based products. The dual catalyst bed was used to catalyze the resulting pyrolysis vapors over it. A maximum bio-oil yield of 44.058 wt.% and gas yield of 28.9 wt.% along with 26.52 wt.% of bio-char is achieved. The biomass product (gas and Bio-oil) was characterized using GC-FID and GC–MS. The dual catalyst bed showed a considerable effect on the bio-oil composition and oxygenates were reduced. The bio-oil exhibit a high quantity of phenols and aromatic. In the gas product, the hydrogen yield has been enhanced from 14.6% to 21.4% and methane yield was enhanced from 20.8% to 23.1%. [ABSTRACT FROM AUTHOR]

In recent years, the most appealing way to harvest solar energy via cost-effective, renewable, clean and sustainable technology is the artificial photocatalysis which has drawn multidisciplinary attention to mitigate the upcoming energy disaster and environmental issues in the arena of sustainable development of society. For this purpose, significant progress has been made, regarding the selectivity of photocatalytic energy sources for potential productivity using solar energy pathway, nonetheless it has still become a difficult task for scientists in order to make and resolve the noteworthy problem of increasing global deterioration. According to a recent literature survey, the non-metal based graphitic carbon nitride (g-C 3 N 4) as a fascinating conjugated polymer based photocatalyst has emerged as a new research hotspot in the form of viable option related to its earth abundant elements, good stability, and ease in fabrication. Still, there are many disadvantages associated with g-C 3 N 4 , such as rapid recombination of photoexcited electron-hole pairs, which ultimately affect the photocatalytic hydrogen (H 2) and carbon dioxide (CO 2) conversion under solar illumination. Previously published several reviews only emphasize the proficient use of g-C 3 N 4 photocatalyst for overall sustainable energy production as an effective treatment strategy. But the literature has never been addressed the use of g-C 3 N 4 with different morphological and structural characteristics for simultaneous H 2 production and carbon dioxide reduction. Therefore, the proper designing and development of novel photocatalysts with proper surface tuning and intrinsic properties towards efficient energy harvesting is of utmost interest. This review article is basically designed to properly address the existing issues and the recent progress of g-C 3 N 4 through various strategies with the aim of obtaining a robust and resourceful photocatalyst towards sustainable energy production. In this context, we had a clear debate regarding the proper tuning of g-C 3 N 4 based photocatalysts through various fabrication strategies, such as electronic structure via metals/non-metals doping, defects engineering, carbon dots, etc. along with Z-scheme heterojunctions, bimetallic cocatalyst, and organic metal-organic framework. At the end, this review is devoted to sufficiently summarizing the recent advancements and the possible future recommendation of the fundamental contribution of g-C 3 N 4 in a wide variety of sustainable energy production fields. [Display omitted] Scheme. Proposed graphical illuatration defining the overveiw of this manuscript. • The photocatalytic main principles of g-C 3 N 4 were comprehensively evaluated. • The key functional characteristics of g-C 3 N 4 photocatalysts were acknowledged. • The various architectural practices for g-C 3 N 4 photocatalysts were described. • The key characteristics of novel g–C 3 N 4 –based composites were outlined. • Significant photocatalytic functionalities of g-C 3 N 4 were discussed in detail. [ABSTRACT FROM AUTHOR]

We confirmed a specific copolymerization (molecular doping) method for the covalent integration of 2,4-dihydroxyoxazole (DHO) monomer within the framework of carbon nitride (CN). The obtained composites xCN/DHO reveal a sophisticated dual-phase photocatalytic activity, which can effectively reduce and oxidize the CO 2 and NO 2 sources in an aqueous solution and simultaneously performed the oxidation of olefin (C C) in an organic state. This momentous dual state activity is concerned with the lipophilicity elevation from the convolution of oxazole (DHO) monomer within the shell of CN semiconductor. This modulation demonstrates the probability of hydrophobic olefin molecules, escorted in the bulk of CN and associated with the oxidation of hydroxyl radicals (∗OH) caused by photogenerated electrons/holes. In this approach, the olefinic compound allusively consumes the photoinduced electrons/holes through elevated CN/DHO, thus stimulating the entire photocatalytic route. Recent research provides a novel strategy for the production of solar fuels upon organic synthesis via the oxidizing capacity of photoinduced holes within free semiconductors of amphiphilic metals. Likewise, the results of the NO 2 photocatalytic reaction demonstrated that molecular doping drastically reduces the oxidative capacity and improves its reducing propensity. More importantly, the CO 2 reduction process supervenes into an extreme aggregation of methane (CH 4) as well as carbon monoxide (CO) in the presence of co-catalyst Pt respectively. The photocatalytic results demonstrate that the copolymerized CN provide the greatest reduction/oxidation potential, which is due to its chemical oxidation phase that causes superior fluctuations in whole performance under solar irradiation. • Synthesis of oxazole (DHO) based carbon nitride (CN) through molecular engineering. • Samples were utilized for photocatalytic CO 2 reduction and NO 2 oxidation. • The momentous activity is concerned towards the convolution of DHO within CN. • Samples alter the probability for hydrophobic olefin molecules due to *OH radicals. • The reduction/oxidation process happen due to excess of electrons/holes in materials. [Display omitted] [ABSTRACT FROM AUTHOR]

Recently, the graphite based heterogeneous photocatalysts has attained tremendous research attention in various environmental applications. Among them, the graphitic carbon nitride (g-C 3 N 4) is categorized as a unique solar active particle with its outstanding intrinsic properties i.e., adequate band configuration, excellent light absorptivity and thermo-physical durability, which make it highly useful and reliable for revenue transformation and ecological concerns. Considering the intrinsic potential of g-C 3 N 4 in photocatalysis, so far, no report has been done in literature for its extraordinary configuration, morphological characteristics and perspective tuning for said applications. To overcome this research gap, our primary emphasis of this review regarding photocatalysis is to provide layout as well as the advancement of visible-light-fueled materials as highly stabilized and extremely effective ones for pragmatic implementation. Thus, this existing comprehensive assessment conducts a systematic survey over visible light driven non-metal novel g-C 3 N 4. The major advancement of this evaluation is the fabrication of well-designed nanosized g-C 3 N 4 photocatalysts with unique configurable frameworks and compositions. Furthermore, alternative techniques in order to customize the analogue band configuration and noticeable cultivation such as metal (cation), nonmetal (anion) doping, worthy metal activating, and alloy initiation with certain semiconductors are discussed in detail. In addition to this, g-C 3 N 4 photocatalytic functionalities towards photocatalytic hydrogen evolution, CO 2 photoreduction, biological metal ions deterioration as well as bacterial sanitization are also presented and discussed in detail. Therefore, we believe that such a pivotal compact assessment can provide a roadmap in several perspectives on the currently underway obstacles in the innovation of effective g-C 3 N 4 catalytic design processes. Moreover, this critical assessment will ultimately serve as a useful supplement in the research area of g-C 3 N 4 nanosized photocatalysts and for the researchers working on its key aspects in diverse range of natural, chemistry, engineering and environmental applications. • Graphitic carbon nitride (g-C 3 N 4) is a metal-free sustainable photocatalyst with a band gap of 2.7 eV. • G-C 3 N 4 has improved light absorption performance as well as electronic features. • Multiple synthetic approaches are being used with g-C 3 N 4 to improve its photocatalytic capabilities. • Metals/nonmetals doping, activation, and alloy formation are employed for g-C 3 N 4 nanocomposites. • Our review includes the latest current g-C 3 N 4 nanocomposites and their photocatalytic implications. [ABSTRACT FROM AUTHOR]

[Display omitted] • Manure digestion at higher solids and temperatures was prone to ammonia inhibition. • Sub-thermophilic (45 °C) was proven the most successful scenario for high CH 4 yield. • Two-stage configuration with prehydrolysis outperformed the single-stage digestion. • The best overall system combination of pHY 45C +HIII 45C raised CH 4 yield by 35.4 % • Rising CH 4 yield was related to microbial abundance and diversity shifts at 45 °C. Solids concentration, temperature, and digester configuration were subjected to biomethanation study to identify effective retrofitting schemes for old swine waste digesters. Batch assays were commenced to determine an appropriate scenario at 30–55 °C and total solids 1–3 %TS. Sub-thermophilic temperature (45 °C) was found desirable with an additional 11.1 % methane yield, while digestion at higher TS induced ammonium inhibition. Subsequent batch experiments lasted 72 hrs for hydrolytic-acidogenic assessment under various temperatures. Heating control at 45 °C and 55 °C for 24 hrs increased hydrolysis efficiency 4.6–5.7 folds above control but showed no significant difference (α = 0.05) between them. Limited heat supply from biogas engine dictated the continuous digestion study to operate pre-hydrolysis reactor at maximum temperature of 45 °C. The two-stage strategy demonstrated best overall performances at the sub-thermphilic combination, raising methane yield by 35.4 %. Next-Generation Sequencing indicated remarkable shifts in abundance and diversity, especially for hydrolytic organisms, which expanded from 54 to 70.2 % by sub-thermophilic temperature. [ABSTRACT FROM AUTHOR]

Due to the future uses of solar energy in different areas, such as the oxidation of fossil fuel-based contaminants, the reduction of carbon dioxide, heterogeneous photocatalysis, and the generation of inexhaustible and renewable hydrogen gas exploits semiconductors. As a metal free photocatalyst, graphitic carbon nitride (g-C 3 N 4) is classified to solve these energy hazards and ecological difficulties owing to its excellent electronic structure with band energy of about 2.7 eV, robust photochemical stability, and better light-harvesting efficiency. However, its photocatalytic performance is still insufficient due to a minor surface area and poor conductivity. Therefore, heterojunction formation by combining it with a giant band gap material is a potential approach to reestablish polarization in its distinctive band structure, increase its light absorption capacity and enhance its surface area. In this regard, various synthesis techniques have been applied so far to integrate g-C 3 N 4 and other materials for boosting its photocatalytic activity. So far, metal oxide, sulfides, and ferrites are three crucial groups of materials that have been identified and defined to be used to synthesize g-C 3 N 4 dependent nanocomposites. As a result, in this review, we have compiled a list of the most recent g-C 3 N 4 nanocomposites with their applications in solar energy adaptation and pollution control. This study concludes an overview about the next steps to study the nanomaterials based g-C 3 N 4 composites and a range of additional insights to solve the present problems. • This review addresses the properties and structures of g-C 3 N 4 photocatalyst structure. • Pros and cons of their synthesis techniques. • The types of the g-C 3 N 4 -based nanocomposite are emphasized. • Approaches to improve the photocatalytic activity of g-C 3 N 4. • The most up-to-date photocatalytic applications were thoroughly discussed. [ABSTRACT FROM AUTHOR]

This study's goal is to maximize the yield of pyrolysis oil utilizing lychee-based biomass for a quick pyrolysis process. Response surface methodology (RSM) and artificial neural network with generalized neural network (GNN) technique were used to optimize the maximum bio-oil yield while considering temperature, heating rate, retention time, and argon gas flow rate as independent variables and bio-oil production as the response. Typical neural networks have constraints such as a long training time, a large number of neurons, and a large number of hidden layers. A generalized neural network (GNN) has been constructed to address these limitations and build a non-linear controller for acquiring access to bio-oil production output. To anticipate bio-oil yield, a new prediction model is proposed that combines the benefits of an auto-adaptive management technique with the rapid reaction of a GNN. Three measures (MSE, RMSE, and R2) are explored in depth to assess the performance efficacy of the models. Based on the finding, 350 °C temperature, 125 min of retention time, 120 °C/min heating rate and 110 mL/min argon flow rate was used to produce the highest bio-oil production (38.43%). Based on techniques, both models used in the study produce equally acceptable outcomes for projecting bio-oil yield. The greatest R2 value for the bio-oil yield ranges from 0.94 to 0.99, and all outcomes are classified as "good" regarding RMSE (all RMSE values are close to one). When all indicators are combined, GNN provides superior accuracy in predicting bio-oil yield in this investigation, followed by ANN. [Display omitted] • Production of bio-oil from lychee-based biomass and maximization by statistical and soft computing techniques. • Temperature, heating rate, retention time and argon flow rate are independent variables and bio-oil production is the response. • 350 °C temperature, 125 min of retention time, 120 °C/min heating rate and 110 mL/min argon flow rate was the optimum condition. • Around 38.43% of bio-oil was produced with chemical compounds making it suitable for various industrial applications. [ABSTRACT FROM AUTHOR]

There is a tremendous increase in global warming due to the pollution enhanced by petroleum product utilization. Lubrication of the machinery parts is the main requirement for the industries, but conventional lubricants are having major problems related to their drainage. So, providing an eco-friendly oil and having better lubricity is a major task in recent research activities. This work performed tribological characteristics of epoxidized Madhuca indica oil while considering SiO 2 nanoparticles as additives. According to the evaluation, the Madhuca indica oil contains more unsaturated fatty acids by means of Gas Chromatography-Mass Spectrometry (GC-MS). The unsaturated fatty acid in the oil was chemically improved by the epoxidation technique to make it more acceptable, and varying quantities of silicon dioxide (SiO 2) were added. The thermo-physical properties of the material, such as kinematic viscosity, viscosity index, pour point, and flash point, as well as its tribological performance, were assessed. An optical microscope was utilized to examine the worn surfaces. The tribological characterization was carried out on a pin on disc wear testing machine. At 100 °C, nanoparticles addition to chemically treated oil results rise in kinematic viscosity of 1.2 wt percent. The addition of SiO 2 nanoparticles resulted in a flash point rise, but the pour point decreased. The presence of SiO 2 in the epoxidized oil improves the consistency of distribution. The addition of 0.8 wt%SiO 2 nanoparticles reduced the coefficient of friction & wear rate. The improved surface wear was observed up to 0.8 wt% concentration of nanoparticles and the same has been verified by worn surface images. • Friction and Wear characteristics of epoxidized oil with SiO 2 nanoparticles as additives. • The tribological analysis was performed on pin on disc machine at fixed operating conditions. • An increase in the viscosity index percentage was seen when the SiO 2 nanoparticles were mixed. • Improved frictional and anti-wear mechanism was observed at 0.4 wt% and 0.8 wt% of nanoparticles concentration. [ABSTRACT FROM AUTHOR]

• A carbon abundant 2‐D structure material 5,8-dibromoisoquinoline (BQ) has been integrated as an aromatic organic monomer within carbon nitride (CN) via molecular aggregation process. • The BQ copolymerized CN with distinguish characteristics leads to a significant increment in the applied application. • The copolymerized samples demonstrating narrowed band gap, high surface area, splendid morphology, and wide optical absorbance which enhanced electron transport ability. • The spinal material, i.e., 10BQ/CN exhibited a superior H 2 evolution of ten‐fold higher activity and also photodegradation of RhB under visible light driven. Graphitic carbon nitride, g-C 3 N 4 (CN) is regarded as an excellent metal-free semiconductor known for its potential solar fuel generation and pollutant degradation. In this study, a carbon richer substance, (5,8-dibromoisoquinoline (BQ)) was used to feed its catalytic function through conventional copolymerization (molecular doping) process at 550°C under a nitrogen atmosphere. The incorporation of BQ monomer in the triazine oligomers of CN in turn enhanced the specific surface area, thereby, improving the lifespan of photoexcited charge carriers, decreasing the charge recombination rate, energy bandgap, and altering the optoelectronic characteristics of CN. On average, the rate of hydrogen (H 2) production over-optimized 10BQ/CN was 710.1 µmol/h much superior and 10 times higher than that of pure CN (71.9 µmol/h). Particularly, the kinetics of the photocatalytic degradation of RhB over 10BQ/CN followed pseudo-order kinetics and the rate constant was three times larger than pure CN. Our results illustrate the crucial importance of conjugated monomers in improving photocatalysis process for future energy demand by providing key steps towards sustainable energy production. [Display omitted]. [ABSTRACT FROM AUTHOR]

The carbon nitride (CN) has good stability, a comprehensive band structure, and a more straightforward fabrication process that makes them a top candidate for hydrogen evolution reaction (HER) and oxygen evolution reaction (OER). So far, scientists have been involved broadly in utilizing smaller carbon-based molecules to modify the CN framework for better-quality solar to fuel energy conversion. Still, the modification of material with a natural macromolecule has been explored insufficiently. In this regard, we firstly a copolymerized carbon nitride (CNP x) by conjugating a novel monomer 2,6-dibenzolumazine with CN through molecular integration (CNP x). The copolymerized catalysts demonstrated noteworthy improvement in photocatalytic activities as compared to pristine CN. Following this, we further combine our superior sample (CNP 5.0) with the underlying biomass-based lignin molecules forming CNP-L x. The biomass-modified CNP-L x obtained through this process has an increased HER and OER under visible light (λ=420 nm). Findings demonstrate the catalytic performance seven times higher for CNP-L x and three times enhanced for CNP x sample than CN catalyst. These improvements can be attributed to the ultrathin nanostructure and efficient visible light absorption of the CN, well-balanced exciton states of the organic monomer, and the synergetic effect of lignin synergetic effect on its surface. Lignin-activated CNP 5.0 photocatalysts produced through this method can prove cost-effective and efficient alternatives for solar overall water splitting. A proposed graphical scheme on conduction band (CB) and valence band (VB) utilizing lignin modified copolymerized CNP for overall water splitting under visible light illumination. [Display omitted] [ABSTRACT FROM AUTHOR]