Self-Powered Disinfection Using Triboelectric, Conductive Wires of Metal-Organic Frameworks

Advances in Triboelectric Nanogenerators for Microbial Disinfection

The global COVID-19 pandemic has highlighted the pivotal role of microbial disinfection technologies, driving the demand for innovative, efficient, and sustainable solutions. Triboelectric technology, known for efficiently converting ambient mechanical energy into electrical energy, has emerged as a promising candidate to address these needs. Self-powered electro-based microbial disinfection using triboelectric nanogenerators (TENGs) has emerged as a promising solution. TENGs have demonstrated effective disinfection capabilities in various settings, including water, air, surfaces, and wounds. This review explores the advancements in TENG-based microbial disinfection, highlighting its mechanisms and applications. By utilizing triboelectric technology, it provides comprehensive insights into the development of sustainable and efficient solutions for microbial control across diverse environments.

Highly efficient microbial inactivation enabled by tunneling charges injected through two-dimensional electronics

Airborne pathogens retain prolonged infectious activity once attached to the indoor environment, posing a pervasive threat to public health. Conventional air filters suffer from ineffective inactivation of the physics-separated microorganisms, and the chemical-based antimicrobial materials face challenges of poor stability/efficiency and inefficient viral inactivation. We, therefore, developed a rapid, reliable antimicrobial method against the attached indoor bacteria/viruses using a large-scale tunneling charge-motivated disinfection device fabricated by directly dispersing monolayer graphene on insulators. Free charges can be stably immobilized under the monolayer graphene through the tunneling effect. The stored charges can motivate continuous electron loss of attached microorganisms for accelerated disinfection, overcoming the diffusion limitation of chemical disinfectants. Complete (>99.99%) and broad-spectrum disinfection was achieved <1 min of attachment to the scaled-up device (25 square centimeters), reliably for 72 hours at high temperature (60°C) and humidity (90%). This method can be readily applied to high-touch surfaces in indoor environments for pathogen control.

Dielectric barrier discharge plasma promotes disinfection-residual-bacteria inactivation via electric field and reactive species

Traditional disinfection processes face significant challenges such as health and ecological risks associated with disinfection-residual-bacteria due to their single mechanism of action. Development of new disinfection processes with composite mechanisms is therefore urgently needed. In this study, we employed liquid ground-electrode dielectric barrier discharge (lgDBD) to achieve synergistic sterilization through electric field electroporation and reactive species oxidation. At a voltage of 12 kV, Pseudomonas fluorescens (ultraviolet and ozone-resistant) and Bacillus subtilis (chlorine-resistant) were completely inactivated within 8 and 6 min, respectively, surpassing a 7.0-log reduction. The lgDBD process showed good disinfection performance across a wide range of pH values and different practical water samples. Staining experiments suggest that cellular membrane damage contributes to this inactivation. In addition, we used a two-dimensional parallel streamer solver with kinetics code to fashion a representative model of the basic discharge unit, and discovered the presence of a persistent electric field during the discharge process with a peak value of 2.86 × 106 V/m. Plasma discharge generates excited state species such as O(1D) and N2(C3Πu), and further forms reactive oxygen and nitrogen species at the gas-liquid interface. The physical process, which is driven by electric field-induced cell membrane electroporation, synergizes with the bactericidal effects of reactive oxygen and nitrogen species to provide effective disinfection. Adopting the lgDBD process enhances sterilization efficiency and adaptability, underscoring its potential to revolutionize physicochemical synergistic disinfection practices.

Aeration-driven piezoelectric activation of peroxymonosulfate achieves effective mitigation of antibiotic resistance dissemination

The antibiotic resistance dissemination in water has become a globally concerned issue, and the wastewater discharge, especially medical wastewater, is considered as one of the most important sources for antibiotic resistance genes (ARGs). However, the effectiveness of current disinfection techniques in the ARGs reduction still remains controversial. In this study, a novel aeration-driven piezoelectric peroxymonosulfate (PMS) activation system using oxygen-vacancy engineered BaTiO3 (BTO) was developed to effectively eliminate antibiotic resistant bacteria (ARB) and ARGs from water. The ARB can be completely inactivated and ∼3.0 logs of ARGs can be removed by the PMS/BTO/aeration system within 1 h, and the spent BTO nanoparticles can be facilely reused after simple rinsing. The aeration can not only provide the driving force for the piezocatalytic process but also more dissolved oxygen in water that played an important role in the generation of free radicals. The radical quenching experiments and electron spin-resonance (ESR) confirmed that all the free radicals, including singlet oxygen (1O2), hydroxyl radical (OH•), sulfate radical (SO4•-) and superoxide radical (•O2-), contributed to the ARGs reduction and 1O2 radicals were identified as the dominant active species. This work provides a high-efficiency and energy saving approach for the mitigation of ARGs from water as the universal use of aeration in water treatment processes and the good reusability of BTO nanoparticles.

A Robust Pyro-phototronic Route to Markedly Enhanced Photocatalytic Disinfection

Photocatalysis offers a direct, yet robust, approach to eradicate pathogenic bacteria. However, the practical implementation of photocatalytic disinfection faces a significant challenge due to low-efficiency photogenerated carrier separation and transfer. Here, we present an effective approach to improve photocatalytic disinfection performance by exploiting the pyro-phototronic effect through a synergistic combination of pyroelectric properties and photocatalytic processes. A set of comprehensive studies reveals that the temperature fluctuation-induced pyroelectric field promotes photoexcited carrier separation and transfer and thus facilitates the generation of reactive oxygen species and ultimately enhances photocatalytic disinfection performance. It is worth highlighting that the constructed film demonstrated an exceptional antibacterial efficiency exceeding 95% against pathogenic bacteria under temperature fluctuations and light irradiation. Moreover, the versatile modulation role of the pyro-phototronic effect in boosting photocatalytic disinfection was corroborated. This work paves the way for improving photocatalytic disinfection efficiency by harnessing the synergistic potential of various inherent material properties.

Collaborative Optimization Design of Self-Powered Sterilizer with Highly Efficient Synergistic Antibacterial Effect

The development of self-powered sterilizers has garnered significant attention in the scientific and engineering fields. However, there remains an urgent need to improve their sterilization efficiency. In this study, we present a self-powered sterilizer with superior antibacterial capability by maximizing the utilization of breakdown discharge generated by a soft-contact freestanding rotary triboelectric nanogenerator (FR-TENG). To achieve this, a collaborative optimization strategy is proposed, encompassing the structural design of the FR-TENG, the implementation of double voltage rectification, and manipulation of the gaseous phase. Through a comprehensive analysis of antibacterial rates and microscopic images, the effectiveness of the self-powered sterilizer against various types of bacteria, including Gram-positive and Gram-negative species, as well as mixed bacteria in natural seawater, is demonstrated. Further investigations into bacterial morphologies and solution compositions reveal that the synergistic effect between electroporation and the generation of reactive oxygen/nitrogen species contributes to efficient sterilization. Additionally, controlled trials and molecular dynamics simulations are conducted to quantitatively elucidate the synergistic antibacterial effect between electroporation and reactive oxygen/nitrogen species. This study highlights the effectiveness of the collaborative optimization strategy in enhancing the sterilization efficiency of self-powered sterilizers while providing valuable insights into the synergistic antibacterial mechanisms of physical and chemical sterilization.

Meta-Aerogel Electric Trap Enables Instant and Continuable Pathogen Killing in Face Masks

The tremendous menace of the COVID-19 pandemic has underscored the urgency for antipathogen masks to stop the transmission of airborne infectious diseases. Most prevailing antipathogen masks manifest a slower sterilization rate that lags behind the pathogen momentum traversing the masks, thereby engendering an elevated susceptibility to infection. Here we tailor nanofibrous meta-aerogel electric traps, 3D-assembled from self-knotted carbon nanotube networks in an all rigid nanofibrous skeleton. This superior configuration revolves around the creation of numerous "dielectrophoretic-aerodynamic grippers", which are capable of directional manipulation of microbes toward the region of the lethal intensive electric field. Based on this, we present a disinfection unit comprising a pair of aerogel electrodes that demonstrate a rapid killing rate (>99.99% biocidal efficacy within 0.016 s) and long-term durability (12 h of continuous operation). Additionally, a microbutton lithium cell is employed as a power supply to fabricate an antipathogen face mask with this disinfection unit, which exhibits superior pathogen inactivation efficacy compared to commercial masks. This scalable biocidal protective equipment holds great potential for use in emergency medical services.

Hybrid energy harvesting systems for self-powered sustainable water purification by harnessing ambient energy

The development of self-powered water purification technologies for decentralized applications is crucial for ensuring the provision of drinking water in resource-limited regions. The elimination of the dependence on external energy inputs and the attainment of self-powered status significantly expands the applicability of the treatment system in real-world scenarios. Hybrid energy harvesters, which convert multiple ambient energies simultaneously, show the potential to drive self-powered water purification facilities under fluctuating actual conditions. Here, we propose recent advancements in hybrid energy systems that simultaneously harvest various ambient energies (e.g., photo irradiation, flow kinetic, thermal, and vibration) to drive water purification processes. The mechanisms of various energy harvesters and point-of-use water purification treatments are first outlined. Then we summarize the hybrid energy harvesters that can drive water purification treatment. These hybrid energy harvesters are based on the mechanisms of mechanical and photovoltaic, mechanical and thermal, and thermal and photovoltaic effects. This review provides a comprehensive understanding of the potential for advancing beyond the current state-of-the-art of hybrid energy harvester-driven water treatment processes. Future endeavors should focus on improving catalyst efficiency and developing sustainable hybrid energy harvesters to drive self-powered treatments under unstable conditions (e.g., fluctuating temperatures and humidity).