Yongbum Kwon

Hydroelectricity energy harvesting has emerged as a promising, eco-friendly alternative for addressing the growing demand for sustainable energy solutions. In this study, we present a hydroelectricity energy harvester fabricated from shredded waste printing paper (WPP), offering a novel waste-to-energy conversion strategy that requires neither material purification nor complex processing. The device leverages the randomly entangled fiber network of WPP to facilitate capillary-driven moisture diffusion and electric double layer (EDL) formation, thereby enabling efficient electrokinetic energy conversion. The random arrangement of WPP fibers increases the effective EDL area, allowing the waste printing paper generator (WPPG) to achieve an open-circuit voltage of 0.372 V and a short-circuit current of 135 μA at room temperature under optimized electrolyte conditions. This study demonstrates that carbon-black-coated WPP can be effectively upcycled into a high-performance hydroelectricity generator, exhibiting excellent electrical output at ambient conditions. By combining material recycling with efficient energy conversion, this system establishes a practical and sustainable pathway for distributed power generation. Overall, this work not only presents an environmentally responsible approach to device fabrication but also highlights that hydroelectricity energy harvesting using WPPG represents a promising alternative energy route for future applications.

The widespread use of single-use face masks during the recent epidemic has led to significant environmental challenges due to waste pollution. This study explores an innovative approach to address this issue by repurposing discarded face masks for hydrovoltaic energy harvesting. By coating the face masks with carbon black (CB) to enhance their hydrophilic properties, we developed mask-based hydrovoltaic power generators (MHPGs). These MHPGs were evaluated for their hydrovoltaic performance, revealing that different mask configurations and sizes affect their efficiency. The study found that MHPGs with smaller, more structured areas exhibited better energy output, with maximum open-circuit voltages (V_OC) reaching up to 0.39 V and short-circuit currents (I_SC) up to 65.6 μA. The integration of CB improved water absorption and transport, enhancing the hydrovoltaic performance. More specifically, MHPG-1 to MHPG-4, which represented different sizes and features, presented mean V_OC values of 0.32, 0.17, 0.19 and 0.05 V, as well as mean I_SC values of 16.57, 15.59, 47.43 and 3.02 μA, respectively. The findings highlight the feasibility of utilizing discarded masks in energy harvesting systems, offering both environmental benefits and a novel method for renewable energy generation. Therefore, this work provides a new paradigm for waste-to-energy (WTE) technologies and inspires further research into the use of unconventional waste materials for energy production.

Water evaporation-driven energy harvesting is an emerging mechanism for contributing to green energy production with low cost. Herein, we developed polyacrylonitrile (PAN) nanofiber-based evaporation-driven electricity generators (PEEGs) to confirm the feasibility of utilizing electrospun PAN nanofiber mats in an evaporation-driven energy harvesting system. However, PAN nanofiber mats require a support substrate to enhance its durability and stability when it is applied to an evaporation-driven energy generator, which could have additional effects on generation performance. Accordingly, various support substrates, including fiberglass, copper, stainless mesh, and fabric screen, were applied to PEEGs and examined to understand their potential impacts on electrical generation outputs. As a result, the PAN nanofiber mats were successfully converted to a hydrophilic material for an evaporation-driven generator by dip-coating them in nanocarbon black (NCB) solution. Furthermore, specific electrokinetic performance trends were investigated and the peak electricity outputs of V_oc were recorded to be 150.8, 6.5, 2.4, and 215.9 mV, and I_sc outputs were recorded to be 143.8, 60.5, 103.8, and 121.4 μA, from PEEGs with fiberglass, copper, stainless mesh, and fabric screen substrates, respectively. Therefore, the implications of this study would provide further perspectives on the developing evaporation-induced electricity devices based on nanofiber materials.

This study investigates the characteristics of the urban heat island by examining the variation in intensity of anthropogenic heat around the Incheon portal area. Higher anthropogenic heat due to the accelerated global climate change has an impact on the strength and properties of local wind circulations, particularly in urban areas. Incheon is the second largest port-city in the Republic of Korea and contains diverse air pollution sources such as a large population, major industry, and ample large marine vessels. As a result of the higher intensity of anthropogenic heat around the Incheon region, the sea breeze is gaining strength, while the strength of land breeze is rapidly decreasing. This sea-land breeze pattern created by the increasing anthropogenic heat around the urban area has significant implications because the strong sea breeze can easily transport maritime air emission to deep inland area, whereas the weak land breeze barely disperses and/or dilutes the accumulated air pollution from the port and city to the surrounding areas. In other words, climate change directly influences anthropogenic heat and will affect not only human society, but also the atmosphere, especially in urban areas. Therefore, the considerations of this study are meaningful to provide further understanding between local wind circulation and air quality of urban areas in coastal regions as well as of the development of suitable management strategies.

Power generation technologies based on water movement and evaporation use water, which covers more than 70% of the Earth’s surface and can also generate power from moisture in the air. Studies are conducted to diversify materials to increase power generation performance and validate energy generation mechanisms. In this study, a water-based generator was fabricated by coating cellulose acetate with carbon black. To optimize the generator, Fourier-transform infrared spectroscopy, specific surface area, zeta potential, particle size, and electrical performance analyses were conducted. The developed generator is a cylindrical generator with a diameter of 7.5 mm and length of 20 mm, which can generate a voltage of 0.15 V and current of 82 μA. Additionally, we analyzed the power generation performance using three factors (physical properties, cation effect, and evaporation environment) and proposed an energy generation mechanism. Furthermore, we developed an eco-friendly and low-cost generator using natural fibers with a simple manufacturing process. The proposed generator can contribute to the identification of energy generation mechanisms and is expected to be used as an alternative energy source in the future.

러시아는 과거 구소련 시절부터 오랫동안 과학기술 및 산업원천기술의 보고(寶庫)로 널리 알려져 있다. 그럼에도 최근 서방 국가의 경제 제재, 산업 인프라의 노후화, 우수 원천기술의 상용화 단절 등으로 인하여 새로운 도약의 원동력이 필요한 시점이다. 반면, 우리나라는 첨단 제조 기술과 더불어 상용화 노하우는 우수하지만, 기술 고도화에 근간이 되는 원천기술 확보에는 어려움이 있어 이를 보완해줄 전략적 파트너가 필요했다. 더욱이 글로벌 가치사슬(Value chain)의 다변화와 중국, 베트남과 같은 신흥 산업국의 가파른 기술력 추격 또한 러시아와 우리나라 모두에게 커다란 위협이 되고있는 실정이기에 양국 간 협력은 중요하다. 본 연구에서는 한-러 양국이 효과적인 기술협력 추진을 위한 방향을 모색하기 위하여 그동안의 다양한 선행연구로부터 한-러 양국 간 협력 현황 및 추진 전략을 아우르고 우리 정부에서 추진하는 9개 다리 행동계획과 함께 분석하고자 하였다. 또한, 러시아 기업(혹은 기관)을 상대로 국내 기업(혹은 기관)과의 기술협력 의향을 조사하여 러시아 측에서 우리나라와 협력을 희망하는 기술분야 및 기술수준에 대하여 분석하였다. 따라서, 본 연구로 하여금 한-러 산업기술 협력 방향에 대한 고찰하고 이를 통하여 향후 양국 간 더 나은 협력추진을 위한 기초자료로 활용 가능할 것으로 기대한다.