## 1 Introduction  
Healthcare-acquired infections (HAIs) are now recognized as a major threat to the safety of patients and healthcare workers worldwide. According to the World Health Organization (WHO), healthcare-acquired infections are one of the leading causes of complications and deaths in hospital patients, leading to millions of infections and hundreds of thousands of deaths worldwide each year [1, 2, 3]. The transmission of bacterial and viral pathogens is a major threat that contributes to the persistence of HAIs [4]. Indirect contact with contaminated surfaces and airborne droplet transmission are the two most common modes of pathogen transmission [5]. Although currently adopted mask standards provide users with basic protection, further research and improvements are needed in terms of particulate matter (PM) filtration efficiency and the inactivation of airborne pathogens [6]. However, the increasing resistance of pathogens to antibiotic drugs has become a worldwide public health problem. Therefore, there is a need to find an alternative to the current conventional antibiotic suppression to avoid the negative effects of drug resistance [7]. Nanofibers have attracted much attention in the field of air filtration by their size effect, high specific surface area, and high porosity [8, 9]. Electrostatic spinning technology is one of the most promising nanofiber fabrication technologies due to the simple equipment, easy control, and low price [10]. Electrostatic spinning technology can make nanofiber materialswith various structures, such as porous fibers, hollow fibers, beaded fibers, and core-shell fibers [11; 12]. Although nonwoven membranes made by stacking electrospun fibers have a large number of voids and pores, these fibrous membranes cannot be considered porous electrospun fibers [13]. Porous fibers should refer to pits or voids on the surface or inside of a single fiber. Porous electrospun fibers have more contact area to intercept contaminant particles in the gaseous medium and load more contaminants due to their higher specific surface area and porosity [14; 15]. The conventional pore formation mechanism of the electrostatic spinning process is similar to template casting [16]. The formation of pores in the electrostatic spinning process is essentially a process that controls the solidification of the polymer in solution. Depending on the strategy of the solidification process, the mechanism of porous formation at this stage can be categorized into thermally induced phase separation (TIPS) involving temperature changes, solvent-induced phase separation (SIPS) by selecting a highly volatile solvent, and non-solvent-induced phase separation (NIPS) by controlling the precursor in solution or the environment [17]. Most polymer electrostatically spun fibers are in a low-crystalline or non-crystalline state [18]. Therefore, porous PET fibers were prepared by an electrostatic spinning technique and a post-processing strategy of non-solvent-induced phase separation. As an emerging class of nanoscale porous materials, metal-organic frameworks (MOFs), which are crystalline structures consisting of metal ions combined with organic ligands, exhibit great potential as carriers of metal ions. These structures are stabilized by chemical bonding between organic ligands and metal ions, which not only maintains their morphological and structural integrity but also effectively restricts their activity, thus achieving stable and slow release of metal ions. Since their first discovery in 1990, MOFs have been investigated for applications in bacteriasis [19; 20; 21; 22], filtration [23; 24; 25; 26; 27], gas storage [28; 29], partitioning, energy storage [30], catalysis [31], water harvesting [32], and drug release [33]. CuBTC (also known as HKUST-1 or MOF-199) was first synthesized and published in 1999 by [PERSON] et al. [34]. Because of its simple synthesis method, excellent thermal stability, and good moisture stability development, it is one of the most fully characterized and widely studied MOF materials to date.