{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,7,18]],"date-time":"2026-07-18T11:55:17Z","timestamp":1784375717205,"version":"3.55.0"},"reference-count":44,"publisher":"MDPI AG","issue":"2","license":[{"start":{"date-parts":[[2026,1,6]],"date-time":"2026-01-06T00:00:00Z","timestamp":1767657600000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"funder":[{"name":"Key Research and Development Program of Changzhi","award":["2024ZDYF015"],"award-info":[{"award-number":["2024ZDYF015"]}]},{"name":"Fundamental Research Program of Shanxi Province","award":["20210302124346"],"award-info":[{"award-number":["20210302124346"]}]},{"name":"Fundamental Research Program of Shanxi Province","award":["20210302124131"],"award-info":[{"award-number":["20210302124131"]}]},{"name":"Fundamental Research Program of Shanxi Province","award":["202403021221230"],"award-info":[{"award-number":["202403021221230"]}]},{"name":"University-level general projects of Changzhi University","award":["XN0775"],"award-info":[{"award-number":["XN0775"]}]}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Molecules"],"abstract":"<jats:p>Converting agricultural solid waste into porous biochar for HCHO adsorption is considered as a \u201ctwo birds with one stone\u201d strategy, which can achieve the environmental goal of \u201ctreating waste with waste\u201d. Unfortunately, the HCHO adsorption performance of pristine biochar is generally unsatisfactory, which is derived from its poor surface activity and insufficient number of pores. In this study, a series of nitrogen-doped porous biochars with adjustable N-containing groups and porosity were synthesized by one-step pyrolysis of melamine and waste jujube pit in different mass ratios (NBC-x, x represented the mass ratio of melamine to waste jujube pit, x = 4\u201312) for HCHO adsorption. The HCHO adsorption tests indicated that the insertion of nitrogen-containing species improved the adsorption capacity of pristine biochar (BC). However, after the insertion of excessive nitrogen-containing species, the porosity of the samples significantly decreased due to the blockage of pores, which could be disadvantageous for HCHO adsorption. DFT calculation results showed that N doping (especially pyrrolic-N) significantly increased the maxima of absolute ESP values of the carbonaceous models and consequently enhanced the affinity between polar HCHO and carbonaceous models (varied from \u221220.65 kJ\/mol to \u221233.26 kJ\/mol). Thus, the NBC-8 possessing both substantial nitrogen content (19.81 wt. %) and developed porosity (specific surface area of 223 m2\/g) exhibited the highest HCHO uptake of 6.30 mg\/g. This was approximately 6.4 times larger than that of BC. This work not only deepens the understanding of the HCHO adsorption mechanism at molecular scale, but also concurrently offers a facile and eco-friendly route of N-doped porous biochar preparation, an efficient technology with high-value utilization of waste biomass resources, and a sustainable method of pollution remediation.<\/jats:p>","DOI":"10.3390\/molecules31020201","type":"journal-article","created":{"date-parts":[[2026,1,6]],"date-time":"2026-01-06T09:40:29Z","timestamp":1767692429000},"page":"201","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":3,"title":["Two Birds with One Stone: One-Pot Conversion of Waste Biomass into N-Doped Porous Biochar for Efficient Formaldehyde Adsorption"],"prefix":"10.3390","volume":"31","author":[{"given":"Qingsong","family":"Zhao","sequence":"first","affiliation":[{"name":"Department of Life Sciences, Changzhi University, Changzhi 046011, China"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Ning","family":"Xiang","sequence":"additional","affiliation":[{"name":"Department of Life Sciences, Changzhi University, Changzhi 046011, China"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Miao","family":"Xue","sequence":"additional","affiliation":[{"name":"Wuhai Branch Station of Inner Mongolia Environmental Monitoring Center, Wuhai 016000, China"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Chunlin","family":"Shang","sequence":"additional","affiliation":[{"name":"Wuhai Branch Station of Inner Mongolia Environmental Monitoring Center, Wuhai 016000, China"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Yiyi","family":"Li","sequence":"additional","affiliation":[{"name":"Department of Life Sciences, Changzhi University, Changzhi 046011, China"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Mengzhao","family":"Li","sequence":"additional","affiliation":[{"name":"Department of Chemistry, Changzhi University, Changzhi 046011, China"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Qiqing","family":"Ji","sequence":"additional","affiliation":[{"name":"Department of Life Sciences, Changzhi University, Changzhi 046011, China"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Yangce","family":"Liu","sequence":"additional","affiliation":[{"name":"Department of Life Sciences, Changzhi University, Changzhi 046011, China"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Hongyu","family":"Hao","sequence":"additional","affiliation":[{"name":"Department of Life Sciences, Changzhi University, Changzhi 046011, China"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Zheng","family":"Xu","sequence":"additional","affiliation":[{"name":"Department of Life Sciences, Changzhi University, Changzhi 046011, China"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Fei","family":"Yang","sequence":"additional","affiliation":[{"name":"Department of Life Sciences, Changzhi University, Changzhi 046011, China"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Tiezheng","family":"Wang","sequence":"additional","affiliation":[{"name":"Department of Life Sciences, Changzhi University, Changzhi 046011, China"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Qiaoyan","family":"Li","sequence":"additional","affiliation":[{"name":"College of Environment and Ecology, Taiyuan University of Technology, Jinzhong 030600, China"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-3929-825X","authenticated-orcid":false,"given":"Shaohua","family":"Wu","sequence":"additional","affiliation":[{"name":"Academy of Environmental and Resource Sciences, School of Environmental Science and Engineering, Guangdong University of Petrochemical Technology, Maoming 525000, China"}],"role":[{"vocabulary":"crossref","role":"author"}]}],"member":"1968","published-online":{"date-parts":[[2026,1,6]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","first-page":"2536","DOI":"10.1021\/cr800399g","article-title":"Formaldehyde in the indoor environment","volume":"110","author":"Salthammer","year":"2010","journal-title":"Chem. Rev."},{"key":"ref_2","doi-asserted-by":"crossref","first-page":"1210","DOI":"10.1016\/j.envint.2009.06.002","article-title":"Formaldehyde in China: Production, consumption, exposure levels, and health effects","volume":"35","author":"Tang","year":"2009","journal-title":"Environ. Int."},{"key":"ref_3","first-page":"112519","article-title":"ZIF-67-derived hierarchical hollow Co3O4@CoMn2O4 nanocages for efficient catalytic oxidation of formaldehyde at low temperature","volume":"528","author":"Xiang","year":"2022","journal-title":"Mol. Catal."},{"key":"ref_4","doi-asserted-by":"crossref","unstructured":"Zhao, Q., Xiang, N., Wen, S., Huo, H., and Li, Q. (2023). ZIF-67 derived Cu-Co mixed oxides for efficient catalytic oxidation of formaldehyde at low-temperature. Catalysts, 13.","DOI":"10.3390\/catal13010117"},{"key":"ref_5","doi-asserted-by":"crossref","first-page":"8066","DOI":"10.1021\/acsami.7b19519","article-title":"A new generation of surface active carbon textiles as reactive adsorbents of indoor formaldehyde","volume":"10","author":"Falco","year":"2018","journal-title":"ACS Appl. Mater. Interfaces"},{"key":"ref_6","doi-asserted-by":"crossref","first-page":"9928","DOI":"10.1021\/es4019892","article-title":"NaOH-modified ceramic honeycomb with enhanced formaldehyde adsorption and removal performance","volume":"47","author":"Yu","year":"2013","journal-title":"Environ. Sci. Technol."},{"key":"ref_7","doi-asserted-by":"crossref","first-page":"585","DOI":"10.1016\/j.cej.2013.06.074","article-title":"Botanical biofiltration of indoor gaseous pollutants\u2014A mini-review","volume":"229","author":"Soreanu","year":"2013","journal-title":"Chem. Eng. J."},{"key":"ref_8","doi-asserted-by":"crossref","first-page":"181","DOI":"10.1021\/es00001a023","article-title":"Destruction of formaldehyde with dielectric denier discharge plasmas","volume":"29","author":"Chang","year":"1995","journal-title":"Environ. Sci. Technol."},{"key":"ref_9","doi-asserted-by":"crossref","unstructured":"Li, Z., Li, Y., Li, S., Ma, J., Ma, Q., Wang, Z., Wang, J., Long, K., and Liu, X. (2024). Enhanced and sustainable removal of indoor formaldehyde by naturally porous bamboo activated carbon supported with MnOx: Synergistic effect of adsorption and oxidation. Molecules, 29.","DOI":"10.3390\/molecules29030663"},{"key":"ref_10","doi-asserted-by":"crossref","first-page":"107390","DOI":"10.1016\/j.jece.2022.107390","article-title":"The intrinsic effects of oxygen vacancy and doped non-noble metal TiO2(B) on photocatalytic oxidation VOCs by visible light driving","volume":"10","author":"Liu","year":"2022","journal-title":"J. Environ. Chem. Eng."},{"key":"ref_11","doi-asserted-by":"crossref","first-page":"2151","DOI":"10.1002\/app.26368","article-title":"Removal of formaldehyde at low concentration using various activated carbon fibers","volume":"106","author":"Song","year":"2007","journal-title":"J. Appl. Polym. Sci."},{"key":"ref_12","doi-asserted-by":"crossref","first-page":"125761","DOI":"10.1016\/j.seppur.2023.125761","article-title":"Promotional mechanism of nitrogen-doping in activated carbon for formaldehyde removal: Enhanced attractive noncovalent interactions coupled with Cannizzaro-type disproportionation reaction","volume":"332","author":"Xiang","year":"2024","journal-title":"Sep. Purif. Technol."},{"key":"ref_13","doi-asserted-by":"crossref","first-page":"452","DOI":"10.1016\/j.jhazmat.2018.12.011","article-title":"High-performance materials for effective sorptive removal of formaldehyde in air","volume":"366","author":"Na","year":"2019","journal-title":"J. Hazard. Mater."},{"key":"ref_14","doi-asserted-by":"crossref","first-page":"38095","DOI":"10.1039\/D5RA05130D","article-title":"Unveiling the promoting mechanism of N-doping in porous biochar for formaldehyde adsorption: Experimental and DFT studies","volume":"15","author":"Xiang","year":"2025","journal-title":"RSC Adv."},{"key":"ref_15","doi-asserted-by":"crossref","first-page":"330","DOI":"10.1002\/sia.6920","article-title":"The role of pore structure and nitrogen surface groups in the adsorption behavior of formaldehyde on resin-based carbons","volume":"53","author":"Su","year":"2021","journal-title":"Surf. Interface Anal."},{"key":"ref_16","doi-asserted-by":"crossref","first-page":"2873","DOI":"10.1016\/j.carbon.2011.02.058","article-title":"Removal of low-concentration formaldehyde in air by adsorption on activated carbon modified by hexamethylene diamine","volume":"49","author":"Ma","year":"2011","journal-title":"Carbon"},{"key":"ref_17","doi-asserted-by":"crossref","first-page":"283","DOI":"10.1016\/j.carbon.2018.05.067","article-title":"Role of sulfur and nitrogen surface groups in adsorption of formaldehyde on nanoporous carbons","volume":"138","author":"Falco","year":"2018","journal-title":"Carbon"},{"key":"ref_18","doi-asserted-by":"crossref","first-page":"156077","DOI":"10.1016\/j.cej.2024.156077","article-title":"Periodate activation with polyaniline-derived carbon for bisphenol A degradation: Insight into the roles of nitrogen dopants and non-radical species formation","volume":"499","author":"Qi","year":"2024","journal-title":"Chem. Eng. J."},{"key":"ref_19","doi-asserted-by":"crossref","first-page":"121809","DOI":"10.1016\/j.seppur.2022.121809","article-title":"Spontaneous formation of nitrogen-doped hierarchical porous microcrystalline nanosheets with improved CO2 capture at low and medium pressures","volume":"301","author":"Tian","year":"2022","journal-title":"Sep. Purif. Technol."},{"key":"ref_20","doi-asserted-by":"crossref","first-page":"594","DOI":"10.1016\/j.jcis.2023.09.099","article-title":"Doping of porous carbons with sulfur and nitrogen markedly enhances their surface activity for formaldehyde removal","volume":"653","author":"Unglaube","year":"2024","journal-title":"J. Colloid Interface Sci."},{"key":"ref_21","doi-asserted-by":"crossref","first-page":"82","DOI":"10.1016\/j.jhazmat.2013.04.049","article-title":"Toward an effective adsorbent for polar pollutants: Formaldehyde adsorption by activated carbon","volume":"260","author":"Lee","year":"2013","journal-title":"J. Hazard. Mater."},{"key":"ref_22","doi-asserted-by":"crossref","first-page":"133367","DOI":"10.1016\/j.jclepro.2022.133367","article-title":"Solvent-free conversion of cucumber peels to N-doped microporous carbons for efficient CO2 capture performance","volume":"369","author":"Kamran","year":"2022","journal-title":"J. Clean. Prod."},{"key":"ref_23","doi-asserted-by":"crossref","unstructured":"He, Q., Xiong, J., Wang, H., Xie, L., Chai, X., Zhang, L., Wang, S., Du, G., and Xu, K. (2025). A comparative study on absorption of gaseous formaldehyde by electrospun biomass carbon nanofiber membranes modified by plasma activation and chemical treatment. Molecules, 30.","DOI":"10.3390\/molecules30102184"},{"key":"ref_24","doi-asserted-by":"crossref","first-page":"155","DOI":"10.1016\/j.micromeso.2019.05.034","article-title":"Combination of alkalinity and porosity enhances formaldehyde adsorption on pig manure-derived composite adsorbents","volume":"286","author":"Suresh","year":"2019","journal-title":"Micropor. Mesopor. Mater."},{"key":"ref_25","doi-asserted-by":"crossref","first-page":"115364","DOI":"10.1016\/j.envres.2023.115364","article-title":"Adsorptivity and kinetics for low concentration of gaseous formaldehyde on bamboo-based activated carbon loaded with ammonium acetate particles","volume":"222","author":"Duan","year":"2023","journal-title":"Environ. Res."},{"key":"ref_26","doi-asserted-by":"crossref","first-page":"119204","DOI":"10.1016\/j.seppur.2021.119204","article-title":"Biomass based N-doped porous carbons as efficient CO2 adsorbents and high-performance supercapacitor electrodes","volume":"275","author":"Li","year":"2021","journal-title":"Sep. Purif. Technol."},{"key":"ref_27","doi-asserted-by":"crossref","first-page":"140158","DOI":"10.1016\/j.scitotenv.2020.140158","article-title":"A new insight into the promotional effect of nitrogen-doping in activated carbon for selective catalytic reduction of NOx with NH3","volume":"740","author":"Li","year":"2020","journal-title":"Sci. Total Environ."},{"key":"ref_28","doi-asserted-by":"crossref","first-page":"11308","DOI":"10.1021\/acssuschemeng.0c03193","article-title":"Superiority of raw biomass and potassium hydroxide in preparation of ultrahigh nitrogen doping of carbon for NH3-SCR reaction","volume":"8","author":"Li","year":"2020","journal-title":"ACS Sustain. Chem. Eng."},{"key":"ref_29","doi-asserted-by":"crossref","first-page":"132133","DOI":"10.1016\/j.jhazmat.2023.132133","article-title":"Catalytic activity and reaction mechanisms of single-atom metals anchored on nitrogen-doped carbons for peroxymonosulfate activation","volume":"459","author":"Wu","year":"2023","journal-title":"J. Hazard. Mater."},{"key":"ref_30","doi-asserted-by":"crossref","first-page":"116120","DOI":"10.1016\/j.indcrop.2022.116120","article-title":"Lignin-derived nitrogen doped hierarchical porous carbon spheres for highly efficient dichloromethane adsorption","volume":"192","author":"Liu","year":"2023","journal-title":"Ind. Crops Prod."},{"key":"ref_31","doi-asserted-by":"crossref","first-page":"128757","DOI":"10.1016\/j.jhazmat.2022.128757","article-title":"Preparation of novel N-doped biochar and its high adsorption capacity for atrazine based on \u03c0-\u03c0 electron donor-acceptor interaction","volume":"432","author":"Cheng","year":"2022","journal-title":"J. Hazard. Mater."},{"key":"ref_32","doi-asserted-by":"crossref","first-page":"116702","DOI":"10.1016\/j.seppur.2020.116702","article-title":"In situ nitrogen functionalization of biochar via one-pot synthesis for catalytic peroxymonosulfate activation: Characteristics and performance studies","volume":"241","author":"Zaeni","year":"2020","journal-title":"Sep. Purif. Technol."},{"key":"ref_33","doi-asserted-by":"crossref","first-page":"24977","DOI":"10.1039\/D0TA07977D","article-title":"The preparation of waste biomass-derived N-doped carbons and their application in acid gas removal: Focus on N functional groups","volume":"8","author":"Li","year":"2020","journal-title":"J. Mater. Chem. A"},{"key":"ref_34","doi-asserted-by":"crossref","first-page":"133640","DOI":"10.1016\/j.fuel.2024.133640","article-title":"Unveiling the promotional mechanisms of N-doping on the adsorption behaviors of dioxins from sintering flue gas by coconut shell-derived hierarchical porous carbon","volume":"381","author":"Ding","year":"2025","journal-title":"Fuel"},{"key":"ref_35","doi-asserted-by":"crossref","first-page":"146115","DOI":"10.1016\/j.cej.2023.146115","article-title":"Towards highly exposed active sites via Edge-N-rich carbon nanosheet@porous biochar for efficient H2S catalytic oxidation","volume":"475","author":"Chen","year":"2023","journal-title":"Chem. Eng. J."},{"key":"ref_36","doi-asserted-by":"crossref","first-page":"5786","DOI":"10.1021\/acs.est.2c00066","article-title":"Insight into the transformation behaviors of dioxins from sintering flue gas in the cyclic thermal regeneration by the V2O5\/AC catalyst-sorbent","volume":"56","author":"Ding","year":"2022","journal-title":"Environ. Sci. Technol."},{"key":"ref_37","doi-asserted-by":"crossref","first-page":"168745","DOI":"10.1016\/j.scitotenv.2023.168745","article-title":"Effect of different defects on the competitive adsorption of formaldehyde and water on the surface of carbon materials: Density functional theory study","volume":"910","author":"Wang","year":"2024","journal-title":"Sci. Total Environ."},{"key":"ref_38","doi-asserted-by":"crossref","first-page":"116109","DOI":"10.1016\/j.fuel.2019.116109","article-title":"Effect of N-doping on NO2 adsorption and reduction over activated carbon: An experimental and computational study","volume":"258","author":"Zhu","year":"2019","journal-title":"Fuel"},{"key":"ref_39","doi-asserted-by":"crossref","first-page":"4511","DOI":"10.1016\/j.ijhydene.2019.12.078","article-title":"Effect of N-doping on the catalytic decomposition of hydrogen iodide over activated carbon: Experimental and DFT studies","volume":"45","author":"Li","year":"2020","journal-title":"Int. J. Hydrogen Energy"},{"key":"ref_40","unstructured":"Frisch, M., Trucks, G., Schlegel, H., Scuseria, G.E., Robb, M., Cheeseman, J.R., Scalmani, G., Barone, V., Petersson, G.A., and Nakatsuji, H. (2016). Gaussian 16, Gaussian, Inc."},{"key":"ref_41","doi-asserted-by":"crossref","first-page":"580","DOI":"10.1002\/jcc.22885","article-title":"Multiwfn: A multifunctional wavefunction analyzer","volume":"33","author":"Lu","year":"2012","journal-title":"J. Comput. Chem."},{"key":"ref_42","doi-asserted-by":"crossref","first-page":"33","DOI":"10.1016\/0263-7855(96)00018-5","article-title":"VMD: Visual molecular dynamics","volume":"14","author":"Humphrey","year":"1996","journal-title":"J. Mol. Graph."},{"key":"ref_43","doi-asserted-by":"crossref","first-page":"101038","DOI":"10.1016\/j.surfin.2021.101038","article-title":"Development of nitrogen-enriched carbon materials by the subtraction method for formaldehyde adsorption","volume":"24","author":"Su","year":"2021","journal-title":"Surf. Interfaces"},{"key":"ref_44","doi-asserted-by":"crossref","first-page":"1473","DOI":"10.1007\/s42823-022-00379-x","article-title":"Preparation of environmental-friendly N-rich chitin-derived activated carbon for the removal of formaldehyde","volume":"32","author":"Ryu","year":"2022","journal-title":"Carbon Lett."}],"container-title":["Molecules"],"original-title":[],"language":"en","link":[{"URL":"https:\/\/www.mdpi.com\/1420-3049\/31\/2\/201\/pdf","content-type":"unspecified","content-version":"vor","intended-application":"similarity-checking"}],"deposited":{"date-parts":[[2026,1,6]],"date-time":"2026-01-06T09:40:49Z","timestamp":1767692449000},"score":1,"resource":{"primary":{"URL":"https:\/\/www.mdpi.com\/1420-3049\/31\/2\/201"}},"subtitle":[],"short-title":[],"issued":{"date-parts":[[2026,1,6]]},"references-count":44,"journal-issue":{"issue":"2","published-online":{"date-parts":[[2026,1]]}},"alternative-id":["molecules31020201"],"URL":"https:\/\/doi.org\/10.3390\/molecules31020201","relation":{},"ISSN":["1420-3049"],"issn-type":[{"value":"1420-3049","type":"electronic"}],"subject":[],"published":{"date-parts":[[2026,1,6]]}}}