Mato Knez

The inherent flexibility and processability of polymers make them indispensable for next-generation flexible electronics, yet their intrinsic electrical properties remain critical bottlenecks. A powerful workaround lies in hybrid materials that challenge this bottleneck by merging organic and inorganic components to unlock unprecedented functionalities through synergies. Beyond composition, area-selective functionalization is equally critical to the practical construction of electronic devices. Here, we demonstrate infiltration of ZnO into a lithographically patterned poly(ethylene terephthalate) (PET) matrix, locally transferring the pattern to the polymer subsurface. Following our approach of area-selective vapor-phase infiltration (AS-VPI), both the region and the depth of infiltration become controllable, even to the micrometer scale. With linear patterns, we demonstrate anisotropic electrical conductivity, showing a difference in resistance of more than 7 orders of magnitude between directions parallel and perpendicular to the infiltrated pattern. The benefit of using VPI to embed ZnO within the polymeric matrix rather than simply coating the surface is demonstrated by the preservation of electrical resistance after bending and deliberate scratching of the sample, as conductive pathways in the subsurface maintain current flow. AS-VPI is therefore demonstrated as an effective strategy for producing electrically functionalized polymers suitable for the design of flexible and wearable electronic devices.

Hypothesis: A nonconductive inverse-opal silica scaffold can regulate photocatalytic interfacial behavior by forming a pore-confined dielectric microenvironment, rather than by acting as an electron-transport pathway.Experiments: A graphitic carbon nitride/bismuth-based oxide and oxyhalide heterostructure was assembled within a three-dimensional inverse-opal silica framework. Surface-potential mapping, irradiated X-ray photoelectron spectroscopy, time-resolved photoluminescence, impedance spectroscopy, spin-trapping electron paramagnetic resonance spectroscopy, and radical-scavenging tests were combined to examine charge redistribution and surface redox utilization.Findings: The optimized confined heterostructure showed an illumination-induced surface-potential increase from 520.2 ± 12.2 to 601.0 ± 17.1 millivolts and an apparent work-function decrease from 4.7812 to 4.7003 electronvolts. The average photoluminescence lifetime shortened from 1.7097 nanoseconds for the unconfined oxide and oxyhalide heterostructure to 1.5086 nanoseconds for the inverse-opal-silica-confined heterostructure. After adsorption equilibrium, ciprofloxacin removal reached 88.15 percent, with 41.01 percent dark adsorption, whereas rhodamine B removal reached 99.54 percent, with 86.96 percent dark adsorption. These results demonstrate adsorption-assisted surface photoredox utilization and support a step-scheme-like interfacial charge-transfer tendency.

The widespread application of photocatalysis, particularly using titanium dioxide (TiO₂), is constrained by its limited visible-light absorption and the challenge of integrating active phases onto practical, complex substrates. We follow a research strategy which utilizes advanced vapor-phase deposition techniques, specifically Atomic Layer Deposition (ALD), Molecular Layer Deposition (MLD) and Vapor Phase Infiltration (VPI), to design, fabricate, and optimize high-performance photocatalytic systems. Our approach enables atomic-level control for the synthesis of tailored materials where composition, nanostructure, and substrate integration are precisely engineered.

Owing to filler sedimentation, aggregation, or migration, the electrostatic dissipative performance of conventional doped polymers often deteriorates during long-term service. To overcome this limitation, this study successfully prepares a polyetherimide/TiO2/ZnO (PEI/TZO) hybrid film via an in-situ co-doping strategy of TiO2 and ZnO, which is based on the top-down vapor phase infiltration (VPI) process using diethylzinc (DEZ), titanium tetrachloride (TiCl4), and H2O as precursors. The distinctive chemical bonds formed between metal oxide precursors and functional groups along the PEI backbone anchor the dopants firmly within the polymer matrix, ensuring structural stability and preventing performance attenuation. Based on the unique layer-by-layer reaction mechanism of VPI, the properties of the modified PEI films are precisely tailored by regulating the TiO2:ZnO doping ratio, thereby achieving controllable and stable electrostatic dissipative behavior. The results demonstrate that the PEI/TZO (1:40) hybrid film reaches an electrical conductivity of 3.56 × 10-5 S cm-1, representing a nine-order-of-magnitude enhancement over pristine PEI and achieving superior electrostatic dissipative performance. Here, dual conductive pathways are constructed both on the surface and within the bulk of the PEI films via the unique VPI process, endowing them with combined surface and intrinsic charge dissipation capabilities. This synergistic dual-discharge mechanism significantly enhances the electrostatic charge dissipation rate and contributes to improved functional durability. Simultaneously, the resulting Ti–O–Zn interfacial network within the polymer matrix improves the thermal stability and UV shielding efficiency while maintaining good visible light transmittance, offering a comprehensive solution for high-performance electrostatic dissipative polymers in precision instrumentation applications.

Owing to filler sedimentation, aggregation, or migration, the electrostatic dissipative performance of conventional doped polymers often deteriorates during long-term service. To overcome this limitation, this study successfully prepares a polyetherimide/TiO2/ZnO (PEI/TZO) hybrid film via an in-situ co-doping strategy of TiO2 and ZnO, which is based on the top-down vapor phase infiltration (VPI) process using diethylzinc (DEZ), titanium tetrachloride (TiCl4), and H2O as precursors. The distinctive chemical bonds formed between metal oxide precursors and functional groups along the PEI backbone anchor the dopants firmly within the polymer matrix, ensuring structural stability and preventing performance attenuation. Based on the unique layer-by-layer reaction mechanism of VPI, the properties of the modified PEI films are precisely tailored by regulating the TiO2:ZnO doping ratio, thereby achieving controllable and stable electrostatic dissipative behavior. The results demonstrate that the PEI/TZO (1:40) hybrid film reaches an electrical conductivity of 3.56 × 10-5 S cm-1, representing a nine-order-of-magnitude enhancement over pristine PEI and achieving superior electrostatic dissipative performance. Here, dual conductive pathways are constructed both on the surface and within the bulk of the PEI films via the unique VPI process, endowing them with combined surface and intrinsic charge dissipation capabilities. This synergistic dual-discharge mechanism significantly enhances the electrostatic charge dissipation rate and contributes to improved functional durability. Simultaneously, the resulting Ti–O–Zn interfacial network within the polymer matrix improves the thermal stability and UV shielding efficiency while maintaining good visible light transmittance, offering a comprehensive solution for high-performance electrostatic dissipative polymers in precision instrumentation applications.

The controlled removal of corrosion products is a persistent challenge in fields ranging from industrial alloy protection to cultural heritage conservation. Achieving high precision and selectivity in subtractive treatments remains difficult because of chemical complexity and structural heterogeneity of the corrosion layers. Inspired by the surface‐chemistry principles of Atomic Layer Etching (ALE), we developed a vapor‐phase strategy termed Chemical Vapor Etching (CVE), which is conceptually analogous to chemical vapor deposition operated in reverse. CVE is demonstrated on artificially corroded Cu‐Sn‐Pb bronze that simulates marine‐aged artifacts. Using Hexafluoroacetylacetone (Hhfac) as a volatilizing agent, corrosion products, including oxides, hydroxides, carbonates, and chloride‐containing phases, are selectively converted into volatile species and removed, whereas the underlying substrate remains unaffected. SEM and XRD confirmed the preservation of surface morphology and phase composition, whereas EDS/XPS revealed the efficient removal of sulfur species and strong reduction of chlorine. The process exhibits tarnish‐limited, self‐terminating behavior, with etching effectively ceasing once a stable Cu/Cu ₂ O interface is reached. By combining chemical selectivity, time‐controlled removal, and non‐line‐of‐sight capability, CVE provides a controllable alternative to conventional mechanical, laser, and plasma‐based cleaning approaches. Beyond bronze conservation, this strategy offers a chemically precise route for managing corrosion in technologically relevant, copper‐based systems.