Graphitic carbon nitride (GCN) has gathered phenomenal research interest as a metal-free, safe, and affordable photocatalyst. However, GCN suffers several problems, such as lower utilization of visible light, higher recombination ratio, slower electron immobility, poor reusability, and a tedious recovery process. Herein, a ternary homojunction (OPACN) was effectively constructed between oxidized GCN (OCN), amino-rich GCN (ACN), and phosphorylated GCN (PCN) and then formulated into 3D hydrogels (OPACN) using pectin as the catalyst support via a crosslinking strategy using FeCl3. The photocatalytic studies using OPACN hydrogel reported 88 % degradation of tetracycline in 30 min with a maximum reusability of 15 cycles. The ternary homojunction hydrogel photocatalyst produced 1204 µM of H2O2 and 404 µM of ammonia in 60 min of visible light irradiation. The phenomenal catalytic activity of the OPACN hydrogel is ascribed to the effective construction of homojunction between the OCN, PCN, and ACN, which facilitated the separation efficiency and boosted the visible light utilization. This study affirmed that the utilization of pectin as a catalytic support enhanced the visible light utilization, reusability, stability, and easiness in recoverability. In addition to this, pectin can act as an electron mediator, and the robust interactions between the GCN components via hydrogen bonding can also facilitate H2O2 production and nitrogen fixation. Overall, this study illuminates the usage of pectin as ideal photocatalytic support for environmental applications.

中文翻译：

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双Z型三元氮化碳同质结果胶微球的构建作为多功能光催化剂用于四环素降解、H2O2生产和N2固定


石墨氮化碳（GCN）作为一种无金属、安全且经济实惠的光催化剂，引起了极大的研究兴趣。然而，GCN存在可见光利用率较低、复合率较高、电子固定性较慢、可重复使用性差以及回收过程繁琐等问题。在此，在氧化GCN（OCN）、富含氨基的GCN（ACN）和磷酸化GCN（PCN）之间有效构建三元同质结（OPACN），然后使用果胶作为催化剂载体通过交联配制成3D水凝胶（OPACN）使用 FeCl3 的策略。使用 OPACN 水凝胶进行的光催化研究表明，四环素在 30 分钟内降解了 88%，最大可重复使用次数为 15 个周期。三元同质结水凝胶光催化剂在可见光照射 60 分钟内产生 1204 µM H2O2 和 404 µM 氨。 OPACN水凝胶的惊人催化活性归因于OCN、PCN和ACN之间同质结的有效构建，这促进了分离效率并提高了可见光利用率。这项研究证实，利用果胶作为催化载体增强了可见光利用率、可重复使用性、稳定性和易于回收性。除此之外，果胶可以充当电子介体，GCN 成分之间通过氢键产生的强大相互作用也可以促进 H2O2 的产生和固氮。总的来说，这项研究阐明了果胶作为环境应用的理想光催化支持物的用途。