Human beings are developing technology day by day. Industry is of great importance in the developing technological process [1]. Therefore, the industry is developing in parallel. This progress is developing further in various branches during the developing industrial process [2, 3]. The industrial process manifests itself in agriculture [4, 5], dyestuffs [6, 7], fertilizers [8–10], food processing processes [11, 12], and many other fields [13, 14]. Industry has many benefits as well as harm to human beings [15, 16]. For example, waste dyestuffs and waste chemicals discharged from processes mix with water and soil, causing serious harm to nature, the ecosystem, and thus the health of living things [17]. For this reason, researchers have turned to studies on the removal of waste dyestuffs and chemicals removed from the processes [18]. Among these studies, photocatalytic degradation studies have become a very remarkable field.
Photocatalysis is a process based on the removal of harmful chemical dyes by using sunlight under UV photons [19, 20]. In photocatalytic studies, photons act as a catalyst and have an effect on the breakdown and removal of dyestuffs [21]. Dyes used in photodegradation studies are generally inductors such as methylene blue (MB) [22], rhodamine B [23], or methyl orange [24]. Various reports have appeared in the literature in this field of study. For example, zinc-oxide nanoparticles were supported with activated carbon to create new nanoparticle derivatives (NPs), and the degradation of rhodamine B with UV was investigated and the efficiency was determined to be 76% [25]. In another study, zinc nanoparticles were synthesized and it was observed that the photocatalytic process was effective under UV light [26]. Photocatalytic studies using titanium oxide nanoparticles also take their place in the literature [27]. As can be seen from these exemplary reports in the literature, nanoparticles are used quite frequently in photocatalytic studies.
Nanotechnology is a branch of science that covers working sizes between 1-100 nm [28–30]. Nanotechnology, which deals with such small-sized particles, therefore enters almost every field of human science [31]. The main ones are fields such as sensors [32–36], energy studies [37–39], photocatalysis [40, 41], chemistry [42, 43], biology [44, 45], medicine [32, 46], optics [47] electronics [48, 49], etc. In photocatalytic reactions, UV light acts as a photocatalyst. Metal nanoparticles create a great synergistic effect by acting as a supporting element for photocatalysts in the photocatalytic process, and photocatalysis occurs faster, more actively, and more efficiently [50]. Bimetallic palladium-zinc nanoparticles were synthesized from Citrus Paradisi (grapefruit peels) and their energy activity and photocatalytic activity took place in previous studies [51]. Trimetallic palladium-platinum-cobalt nanoparticles synthesized from Malus domestica peels (red apple peels) also took their place in photocatalytic activity [52]. As can be understood from here, nanoparticle production from natural resources as green synthesis has a highly interesting feature.
Green synthesis is a synthesis method carried out from plant leaves [53, 54], plant roots [55, 56], plant bodies [57, 58], algae [59], fungi [60], bacteria [61], and completely natural resources in nature [58]. The advantage of green synthesis is that it does not contain chemicals and is a process that is extremely friendly to the health of living things and the ecosystem [58, 62]. In previous studies, nanoparticle production from Nigella Sativa seeds (black cumin seeds) has taken its place in the literature [44, 63]. Likewise, nanoparticle studies synthesized from propolis, a honey product, have also been reported [64]. In this study, synthesizing zinc nanoparticles from Hypericum calycinum L. leaves using the green synthesis method and carrying out the photocatalytic process attracted our attention due to their functional functions and groups, which have a feature that attracts much attention.
In this study, zinc nanoparticles (Zn NPs) were synthesized from Hypericum calycinum L. leaves by a biogenic method using green synthesis, and their photocatalytic activation was examined. To better observe the morphological structure of Zn NPs, photocatalytic activation efficiency was calculated by taking ultra-violet visible (UV-Vis), transmission electron microscopy (TEM), X-ray diffraction analysis (XRD) and Fourier infrared microscopy (FTIR) characterizations.