The promotion effect of carbon quantum dots derived from maize stalks on the photosynthesis of maize growth

Abstract

This study described the preparation of water-soluble carbon quantum dots (CQDs) from maize stalks via a hydrothermal method at 200 °C for 10 h. The prepared CQDs exhibited an average particle size of 2.03 nm with a graphene structure, and the surfaces contained hydroxyl and carboxyl functional groups. For the aqueous solution of CQDs at a concentration of 100 mg/L, the optimal excitation wavelength was 410 nm, and the maximum emission wavelength was 495 nm. By utilizing the down-conversion luminescence properties of CQDs to enhance photosynthesis in maize growth, it was found that the optimal CQD concentration was 25 mg/L when maize seedlings were sprayed with CQDs at different concentrations for 7 days. The maize plant height, leaf area, leaf length, leaf circumference, chlorophyll content, Hill reaction activity, total photosynthetic rate, and net photosynthetic rate significantly increased by 43.2%, 25.6%, 31.2%, 27.3%, 35.2%, 45.5%, 29.8% and 46.6% compared with the CK, respectively. This work developed and demonstrated a feasible strategy for synthesizing cost-effective CQDs and may offer a potential benefit for early-stage corn seedling growth under controlled conditions.

Keywords

Carbon quantum dots / Hydrothermal method / Chlorophyll content / Photosynthesis rate

References

[1] Astari L, Belleville B, Ozarska B, Umemura K, Crawford R, Kusumaningrum WB, Ismayati M. Performance of self-binding engineered panels made from sweet corn stalks (Zea mays L.) for furniture applications. Bioresour Technol Rep, 2024.

[2] Bhatia P, Chaira T, Gupta LK. Therapeutic applications of carbon quantum dots (CQDs): a review. J Inorg Organomet Polym Mater, 2024, 35532433259.

[3] Cao Y, Zhou B. Ecotypic variation in photosynthesis, stomatal conductance, and water use efficiency of Illicium lanceolatum in response to light intensity under drought and recovery. Plants (Basel), 2026.

[4] Chao-Mujica FJ, Garcia-Hernández L, Camacho-López S, Camacho-López M, Camacho-López MA, Reyes Contreras D, Pérez-Rodríguez A, Peña-Caravaca JP, Páez-Rodríguez A, Darias-Gonzalez JG, Hernandez-Tabares L, Arias de Fuentes O, Prokhorov E, Torres-Figueredo N, Reguera E, Desdin-García LF. Carbon quantum dots by submerged arc discharge in water: synthesis, characterization, and mechanism of formation. J Appl Phys, 2021.

[5] Chen W, Zhang K, Xu C, Zhang F, Du L. Preparation of MDEA derived nitrogen-doped CQDs nanofluids and their CO₂ capturing performance and mechanism investigation. Separat Purif Technol, 2024.

[6] Cheng B, Yang Z, Chen F, Yue L, Cao X, Li J, Qian HL, Yan XP, Wang C, Wang Z. 2023. Biomass-derived carbon dots with light conversion and nutrient provisioning capabilities facilitate plant photosynthesis. Science of The Total Environment, 901, 165973. https://doi.org/10.1016/j.scitotenv.2023.165973

[7] Chowmasundaram YAP, Tan TL, Fadzil NI, Nulit R, Jusoh M, Rashid SA. Foliar application of carbon quantum dots photosynthesis enhancer for enhancing the growth and development of green mustard (Brassica juncea) in indoor hydroponics. J Photochem Photobiol A Chem, 2025.

[8] Dhiman S, Debnath N, Das S. Carbon based photosynthetic biohybrid system: a new approach to energy conversion. BioNanoScience, 2024, 14549104929.

[9] Feng Y, Gong S, Chen H, Zhang Y, Zhang H. Phytic acid-modified corn stalks assisted by supercritical carbon dioxide for Cu²⁺ adsorption. Chem Pap, 2025, 79532053219.

[10] Fu W, Li Z, Han J, Zhang Z, Wang F. Inspired by plants: carbonization mechanism, micro architecture and electrochemical applications of corn stalks. Carbon N Y, 2023, 204: 516-525.

[11] Gan L, Wang J, Gu S, Wang J, Xie J, Yao N, Yan X, Lv N. 2026. From waste to worth: valorizing lawn waste into carbon dots for saline agricultural enhancement. Bioresource Technology, 456, 134943. https://doi.org/10.1016/j.biortech.2026.134943

[12] Haider Z, Yang C, Ahmad I, Zia S, Javaid MH, Rehman M, Yasin MU, Ali B, Nana C, Gan Y. 2024. Bioderived carbon quantum dots boost maize growth and photosynthesis by augmenting UV spectrum absorption and carbon assimilation regulatory genes. Journal of Environmental Chemical Engineering, 12(6), 114396. https://doi.org/10.1016/j.jece.2024.114396

[13] He C, Zhu H, Kong X, Li C, Yan X. Environmental effects of returning rice and wheat straw to fields. Agric Sci Technol, 2017, 9: 1710-1715.

[14] Jawad MM, Abdullah LA. Novel characteristics of CQDs synthesized by electrochemical method. J Opt, 2024, 543631639.

[15] Jia S, Liu Z, Gao Y, Zhang R, Zhu R, Gao S, Guan P, Geng X, Tian K, Bai S. Carbon quantum dots (CQDs) modified α-Fe₂O₃/BiVO₄ heterojunction photoanode for enhancing photoelectrochemical water splitting. Electrochimica Acta, 2025.

[16] Koç Keşir M, Ayazoglu Demir E, Yılmaz MD. NS-CQDs/TiO₂ hybrid nanocomposites incorporated with nutshell derived NS-CQDs as photocatalyst for environmental/biological applications and cytotoxicity effect. J Environ Chem Eng, 2025.

[17] Kopylchuk HP, Voloshchuk OM, Pasailiuk MV. Comparison of total amino acid compositions, total phenolic compounds, total flavonoid content, β-carotene content and hydroxyl radical scavenging activity in four wild edible mushrooms. IJM Italian J Mycol, 2023, 52: 112-125.

[18] Liang FW, Chen JY, He JL, Liu Z, Xu WC, Huang YJ, Liao XD, Xing SC. Facilely prepared N-modified carbon quantum dots as microalgal photosynthesis promoters for wastewater treatment. J Environ Manage, 2025, 390. 126404

[19] Liu YY, Yu NY, Fang WD, Tan QG, Ji R, Yang LY, Wei S, Zhang XW, Miao AJ. Photodegradation of carbon dots cause cytotoxicity. Nat Commun, 2021, 121812

[20] Liu Y, Zhang C, Zhang T, Wang X, Yang X, Zeng D, Zou M, Zhang Y. Enhanced catalytic performance of CQDs/Ba_0.9Ca_0.1TiO₃ through up-conversion luminescence effect and photo-piezoelectric co-catalysis. Ceram Int, 2025, 51121566215671.

[21] Meng Y, Wu K, Gong P, Zhang Z, Han M, Wei Z, Wang L, Lv N, Bai W, Zhang L. Effects of corn stalks returning on soil microbial carbon use efficiency and corn yield in semi-arid cropland. BioResources, 2023, 191103115.

[22] Mo F, Chen Q, Zhang X. Synthesis of hollow calcium carbonate microspheres by a template method for DOX loading and release with carbon dots photosensitivity. Materials (Basel), 2022.

[23] Mohammed HA, Aziz DM, Aziz SB, Nofal MM, Hamasalih GH, Hussein II, Kayani KF, Mohammed PA, Sangaraju S. Eco-friendly fabrication of flag blue flower-derived CQD-doped chitosan films with tunable optical and photoluminescent properties. Sci Rep, 2025, 1613030

[24] Mu L, Wu W, Huang J, Peng H, Song Y, Tao J, Chen G. Simultaneous synthesis of carbon quantum dots and hydrothermal biochar from corn straw through hydrothermal treatment. Ind Crops Prod, 2024, 219. 119026

[25] Mu P, Han Y, Wang J. Gram-scale green-emission carbon quantum dots produced from wood via the hydrothermal synthesis method for the detection of Fe (III). Appl Sci (Basel), 2025.

[26] Pal A, Sk MP, Chattopadhyay A. Recent advances in crystalline carbon dots for superior application potential. Mater Adv, 2020, 14525553.

[27] Ren H, Labidi A, Gao T, Padervand M, Liang X, Wang C. Efficient conversion of bio-waste lignin into high-value fluorescent nitrogen-modified carbon quantum dots for live-cell imaging. Industr Crops Products, 2024.

[28] Scafaro AP, Posch BC, Evans JR, Farquhar GD, Atkin OK. Rubisco deactivation and chloroplast electron transport rates co-limit photosynthesis above optimal leaf temperature in terrestrial plants. Nat Commun, 2023, 1412820

[29] Shabazi A, Dall E. Synthesis of quantum carbon dots (CQDs) from hard walnut skin by hydrothermal method. Amirkabir J Civil Eng, 2023, 553103106.

[30] Sharma A, Sharma V, Gathania AK. Enhancing photoluminescence properties of reddish-orange emitting phosphor cerium fluoride doped with Eu³⁺ by the incorporation of N-CQDs. J Alloys Compds, 2025.

[31] Shi J, Pu K, Zhao T, Shi J, Zheng N, Nie L, Xue K, Gao Y. One-step hydrothermal synthesis of CQDs/TiO₂/NH₂-MIL-125 for efficient photocatalytic production of H₂O₂ under visible light. J Environ Sci (China), 2025, 152: 637-653.

[32] Thonghlueng J, Sangwongchai W, Chuaephon A, Toomjeen P, Matulakul P, Terasart PC, Apaisom K, Promarak V, Chonlateeroj P, Ittisanronnachai S, Sakonsinsiri C, Thitisaksakul M, Puangmali T. In situ coffee ground-derived carbon dots as a sustainable antenna for photosynthesis enhancement: Experimental and DFT mechanistic insights. Industrial Crops and Products, 2026;247.https://doi.org/10.1016/j.indcrop.2026.123481

[33] Tran NB, Nguyen QK, Ngoc Dang TM, Tran TD, Nguyen TM, Thuong Nguyen TK, Vu DT, Pham B, Huong Nguyen TA, Mai Pham TN. Nitrogen doped carbon quantum dots (N-CQDs) synthesized by a microwave assisted hydrothermal method in combination with gold nanoparticles (AuNPs) as sensitive dual sensor for antibiotic meropenem detection. Microchem J, 2025.

[34] Viji S, Dinesh A, Radhakrishnan K, Priya LS, Sivasankari C, Santhamoorthy M, Ayyar M, Mohanavel V, Hashem M, Fouad H, Ramachandran G, Santhoshkumar S. One-pot green synthesis of BSA-capped O-CQDs as an effective fluorescent sensing platform for sensitive and selective detection of promethazine drug. Sens Bio-Sens Res, 2025.

[35] Wang Y. Study on the degradation conditions of corn stalks by Asian corn borer digestive enzymes combined with white-rot fungus. Sci Prog, 2024, 1071368504241239447

[36] Xu X, Wang X, Du W, Liu S, Qiao Z, Zhou Y. Hydrothermal synthesis of biomass-derived CQDs: advances and applications. Nanotechnol Rev, 2025.

[37] Yang T, Wang X, Liu H, Zhao Q, Gong K, Li W, Liang Y, Wang X. An inorganic-organic hybrid CQDs@PVP lubricant additive: achieving low friction and wear in PEG and water. Friction, 2024, 121022812297.

[38] Yang X, Fu S, Basta AH, Lucia L. A true biomass standout: Preparation and application of biomass-derived carbon quantum dots. Bioresources, 2024.

[39] Zhao J, Yu L, Ma H, Zhou F, Yang K, Wu G. Corn stalk-based activated carbon synthesized by a novel activation method for high-performance adsorption of hexavalent chromium in aqueous solutions. J Colloid Interface Sci, 2020, 578: 650-659.

[40] Zhao B, Xing Y, Xue Y, Chen N, Sun C, Li M, Shi H, Ma B, Wang S, Tang Y, Liu J. Efficient degradation of dye wastewater with a novel tribocatalytic process initiated by CQDs-Bi2MoO6 catalyst: preparation, degradation, kinetics, DFT calculations and mechanism. Chem Eng J, 2025.

[41] Zhao K, Huang Z, Saed YA, Sun X, Zheng Z. Biomass derived carbon dots from green synthesis to multimodal bioimaging applications. Discover Nano, 2026.

[42] Zhu SC, Hu QY. Unraveling the structural transition mechanism of room-temperature compressed graphite carbon. Phys Chem Chem Phys, 2021, 23362056020566.

Funding

Science and Technology Program of Inner Mongolia Autonomous Region(2025YFSH0028)

Science and Technology Program of the Inner Mongolia Autonomous Region(2026YFHH0149)

Funds for the Transfer and Transformation of Agricultural and Pastoral Science and Technology(2026TG18-6)

Rights & permissions

The Author(s)