000170007 001__ 170007
000170007 005__ 20260316092629.0
000170007 0247_ $$2doi$$a10.3390/catal16020184
000170007 0248_ $$2sideral$$a148574
000170007 037__ $$aART-2026-148574
000170007 041__ $$aeng
000170007 100__ $$aFlorentino-Madiedo, L.
000170007 245__ $$aImpact of post-annealing on the water splitting performance of polymeric carbon nitride: the role of hydrogen bonds
000170007 260__ $$c2026
000170007 5060_ $$aAccess copy available to the general public$$fUnrestricted
000170007 5203_ $$aPost-annealing treatments constitute a simple and cost-effective strategy to tailor the structure and photocatalytic performance of polymeric carbon nitride (PCN). In this work, PCNs synthesized from melamine and urea were subjected to post-annealing at 580 °C under air and CO2 atmospheres to elucidate the role of hydrogen bonding, as well as other structural modifications induced by oxidizing atmospheres, on photocatalytic water splitting. Comprehensive structural, chemical, and textural characterization (XRD, FTIR spectroscopy, XPS, SSNMR, HRTEM, BET, TGA, and UV–Vis DRS) reveals that post-annealing induces markedly different effects depending on the precursor. For melamine-derived PCN, the treatment selectively disrupts hydrogen bonds between melon strands without introducing nitrogen vacancies, amorphization, or framework shortening. This structural rearrangement increases surface area, reduces particle size, slightly widens the band gap, and enhances water–framework interactions, resulting in a twofold improvement in the hydrogen evolution rate (HER), reaching ~3300 µmol h−1 g·cat−1 under visible-light irradiation. In contrast, urea-derived PCN undergoes only minor structural modifications, including slight exfoliation and possible nitrogen deficiency, which do not translate into a measurable enhancement of photocatalytic activity. These results demonstrate that selective hydrogen-bond disruption is a key factor governing charge transport and photocatalytic efficiency in PCN. Importantly, the optimized melamine-derived PCN achieves HER values comparable to those of urea-derived PCN while maintaining a substantially higher synthesis yield, highlighting its potential for scalable solar hydrogen production.
000170007 536__ $$9info:eu-repo/grantAgreement/ES/CSIC/2020-80E129
000170007 540__ $$9info:eu-repo/semantics/openAccess$$aby$$uhttps://creativecommons.org/licenses/by/4.0/deed.es
000170007 655_4 $$ainfo:eu-repo/semantics/article$$vinfo:eu-repo/semantics/publishedVersion
000170007 700__ $$aVega, M. F.
000170007 700__ $$aRodríguez, N.
000170007 700__ $$aBarriocanal, C.
000170007 773__ $$g16, 2 (2026), 184 [33 pp.]$$pCatalysts$$tCatalysts$$x2073-4344
000170007 8564_ $$s18683930$$uhttps://zaguan.unizar.es/record/170007/files/texto_completo.pdf$$yVersión publicada
000170007 8564_ $$s2504086$$uhttps://zaguan.unizar.es/record/170007/files/texto_completo.jpg?subformat=icon$$xicon$$yVersión publicada
000170007 909CO $$ooai:zaguan.unizar.es:170007$$particulos$$pdriver
000170007 951__ $$a2026-03-16-08:16:42
000170007 980__ $$aARTICLE