https://scholar.dgist.ac.kr/handle/20.500.11750/250 2026-04-04T13:10:07Z 2026-04-04T13:10:07Z 김동윤 인수일 https://scholar.dgist.ac.kr/handle/20.500.11750/56803 2025-07-25T02:42:16Z 2023-10-18T15:00:00Z

Title: 1T/2H-MoS₂ interaction with reduced TiO₂ for photocatalytic CO₂ reduction into CO Author(s): 김동윤; 인수일 Abstract: Photocatalytic CO2 reduction is a potential technique for converting solar energy and greenhouse gases into value-added chemicals. However, the main obstacles are limited light absorption and poor charge separation of electron-hole pairs. Here, we have developed a highly stable, phase-controlled heterostructured photocatalyst of molybdenum sulfide with reduced titania (1T/2H-MoS2@RT) for CO2 reduction into CO. The optimized 1T/2H-MoS2@RT produced 1480.1 ppm g−1 h−1 of CO. The catalyst showed ∼5 and ∼19 times higher activity than RT and MoS2, respectively, and excellent stability over 48 h (8 cycles). Our investigation revealed that combining MoS2 with RT synergizes the selective conversion of CO2 to CO. MoS2 acts as a visible light sensitizer and electron transport bridge; however, RT extracts electrons from MoS2 because of its lower energy potential. Improved light absorption, CO2 adsorption, and rapid electron-hole separation are responsible for the increased catalytic activity and stability.

2023-10-18T15:00:00Z 김화평 인수일 https://scholar.dgist.ac.kr/handle/20.500.11750/56795 2025-07-25T02:41:53Z 2023-11-21T15:00:00Z

Title: Defect Engineering of Ternary Cu–In–Se Quantum Dots for Boosting Photoelectrochemical Hydrogen Generation Author(s): 김화평; 인수일 Abstract: Cu-In-Se quantum dot are promising materials for solar fuel generation due to tunable band gap, high absorption coefficiecnt, low toxicity. Although defects significantly affect the photoelectrochemical performacne and photophysical properties of quantum dot, the effects of defects have not studied sufficiently yet. Herein, we developed the defect engineering of Cu-In-Se quantum dot for highly efficient solar fuel conversion. Lewis acid and base reaction between oleyammonium selenocarbamate and metal halide-oleyamine complexs are modulated to realize Cu-In-Se quantum dot with the tunable amount of Cu vacancies without changing their morphology. Among them, CISe QD with In/Cu = 1.55 ratio exhibited the most excellent photoelectrochemical hydrogen production with outstanding photocurrent density up to 10.7 mA cm-2 (at 0.6 VRHE), caused by enhanced carrier concentration & lifetimes of the quantum dot and suitable electronic and band structure. The suggestion which can efficiently control the defects in heavy-metal free ternary quantum dot, provides the detail understanding of the effects of defects and offers a practical approach to improve photoelectrochemical hydrogen evolution.

2023-11-21T15:00:00Z In, Su Il https://scholar.dgist.ac.kr/handle/20.500.11750/47268 2025-07-25T02:40:10Z 2017-03-02T15:00:00Z

Title: Hybrid CuxO-TiO2 Heterostructured composites for Photocatalytic CO2 Reduction into Methane by Solar Irradiation Sunlight into Fuel Author(s): In, Su Il Abstract: Photocatalytic CO2 conversion to fuel offers an exciting prospect for solar energy storage and transportation thereof. Several photocatalysts have been employed for CO2 photoreduction; the challenge of realizing a low-cost, readily synthesized photocorrosion-stable photocatalytic material that absorbs and successfully utilizes a broad portion of the solar spectrum energy is as yet unmet. Herein, a mesoporous ptype/n-type heterojunction material, CuxO−TiO2 (x = 1, 2), is synthesized via annealing of Cu/Cu2O nanocomposites mixed with a TiO2 precursor (TiCl4). Such an experimental approach in which two materials of diverse bandgaps are coupled provides a simultaneous opportunity for greater light absorption and rapid charge separation because of the intrinsic p−n heterojunction nature of the material. As detailed herein, this heterostructured photocatalyst demonstrates an improved photocatalytic activity. With the CO2 reduction of our optimal sample (augmented light absorption, efficacious charge separation, and mesoporosity) that utilizes no metal cocatalysts, a remarkable methane yield of 221.63 ppm·g−1 ·h−1 is achieved.

2017-03-02T15:00:00Z In, Su-Il 곽영섭 Kim, Hye Rim Razzaq, Abdul Lee, Kyeong-Seok 김희영 창수찬 이봉효 CraigA.Grimes 양재하 https://scholar.dgist.ac.kr/handle/20.500.11750/47066 2025-07-25T02:39:24Z 2017-11-10T15:00:00Z

Title: Hierarchical MicroNano-Porous Acupuncture Needles Offering Enhanced Therapeutic Properties Author(s): In, Su-Il; 곽영섭; Kim, Hye Rim; Razzaq, Abdul; Lee, Kyeong-Seok; 김희영; 창수찬; 이봉효; CraigA.Grimes; 양재하

2017-11-10T15:00:00Z