한양대학교 · 재료과학
Muhammad A. Abbas 교수의 연구실은 나노금속 클러스터와 반도체 양자점 등 나노소재를 활용한 고효율 에너지 변환 시스템 개발에 중점을 두고 있습니다. 특히 금 및 silver 나노클러스터의 분자적 특성과 흥분 상태 동역학을 활용한 광촉매 및 태양전지 응용 연구를 선도하고 있으며, 안정성과 효율성을 동시에 향상시키기 위한 신소재 합성 및 표면 제어 기술을 개발하고 있습니다. 또한, 전기화학적 촉매와 자율주행 차량 제어 알고리즘 등 다학제적 에너지 기술 연구도 함께 진행하고 있습니다.
표시된 성과는 수집된 데이터 기준으로 산출되며, 일부 차이가 있을 수 있습니다.
Few-atom gold nanoclusters (NCs) exhibit molecule-like properties due to a discrete electronic structure driven by the quantum confinement effect. Unlike plasmonic Au particles, these nonplasmonic particles of diameter less than 2 nm, commonly referred to as nanoclusters, possess a distinct excited-state behavior that can offer a new opportunity to employ them as a photosensitizer. Their size-dependent excited-state behavior enables establishing logical designing principles to build up efficient
It is well-known that platinum (Pt) is the best electrocatalyst currently available. However, its high cost and scarcity have hindered the commercialization of many green technologies that require the use of Pt electrocatalysts. To pave the way for mass production, the search for alternative electrocatalysts was initiated by researchers working in the fuel cell area, and it has been rapidly expanded to other energy applications in the past few years. Our discussion in this perspective starts wit
Gold nanoclusters (Au NCs) with molecule-like behavior have emerged as a new light harvester in various energy conversion systems. Despite several important strides made recently, efforts toward the utilization of NCs as a light harvester have been primarily restricted to proving their potency and feasibility. In solar cell applications, ground-breaking research with a power conversion efficiency (PCE) of more than 2% has recently been reported. Because of the lack of complete characterization o
Despite the potential of PbS quantum dots (QDs) as sensitizers for quantum-dot-sensitized solar cells (QDSSCs), achieving a high photocurrent density over 30 mA cm(-2) remains a challenging task in PbS-sensitized solar cells. In contrast to previous attempts, where Hg(2+)-doping or multi-step post-treatment is necessary, we are capable of achieving a high photocurrent exceeding 30 mA cm(-2) simply by manipulating the successive ionic layer adsorption and reaction (SILAR) method. We show that con
A Nonlinear model predictive control (NMPC) for trajectory tracking with the obstacle avoidance of autonomous road vehicles traveling at realistic speeds is presented in this paper, with a focus on the performance of those controllers with respect to the look-ahead horizon of the NMPC. Two different methods of obstacle avoidance are compared and then the NMPC is tested in several simulated but realistic tracking scenarios involving static obstacles on constrained roadways. In order to simplify t
Intrinsic low stability and short excited lifetimes associated with Ag nanoclusters (NCs) are major hurdles that have prevented the full utilization of the many advantages of Ag NCs over their longtime contender, Au NCs, in light energy conversion systems. In this report, we diagnosed the problems of conventional thiolated Ag NCs used for solar cell applications and developed a new synthesis route to form aggregation-induced emission (AIE)-type Ag NCs that can significantly overcome these limita
One way to revolutionize solar energy production and expand it to a large scale is to reduce the manufacturing cost and complexity of the fabrication process. The ability to make solar cells on the surface of any shape would further transform this technology. Quantum dot-sensitized solar cells (QDSSCs) are an ideal candidate to push solar cell technology in this direction. In this regard, making a paint that can be applied by a paint brush to any transparent conductive surface to turn it into th
TiO<sub>2</sub> offers several advantages over graphite as an anode material for Li-ion batteries (LIBs) but suffers from low electrical conductivity and Li-diffusion issues. Control over defect chemistry has proven to be an effective strategy to overcome these issues. However, defect engineering has primarily been focused on oxygen vacancies (V<sub>O</sub>). The role of another intrinsic TiO<sub>2</sub> vacancy [i.e., titanium vacancies (V<sub>Ti</sub>)] with regard to the Li<sup>+</sup> storag
Entropy-stabilized titanium niobium oxides (TNOs) with crystallographic shear structures (e.g., TiNb2O7 and Ti2Nb10O29) are generally synthesized by high-temperature calcination in an air or an oxygen atmosphere to compensate for their positive enthalpies of formation. In this work, we demonstrate that changing the reaction atmosphere into a slightly reductive environment using in situ carbonization leads to the creation of a new class of TNO with a formula of TiNbO4. Unlike its predecessors, th
A Nonlinear Model Predictive Controller (NMPC) for trajectory tracking of autonomous vehicles is presented in this paper. This controller is tested under several constrained scenarios including static obstacle avoidance and avoidance of obstacles with more complex constraints. In the latter case the real life necessary constraint of remaining on the road while performing the obstacle avoidance manoeuvers is implemented. The resulting controllers are applied and tested in a simulation environment
Metal nanoclusters (NCs) are a recent addition to the family of traditional photosensitizers (e.g., dyes and quantum dots) for TiO2-based photoelectrodes. Despite the resemblance between NC-based and traditional sensitized photoelectrodes in their design architecture, recent studies have revealed that the photoelectrochemical behavior of NC–TiO2 photoelectrodes differs from that of their traditional counterparts. Here, we use impedance spectroscopy to shed light on another different behavior of
Abstract — This research paper describes the design and implementation of an autonomous room air cooler using fuzzy rule based control system. The rule base receives two crisp input values from temperature and humidity sensors, divides the universe of discourse into regions with each region containing two fuzzy variables, fires the rules, and gives the output singleton values corresponding to each output variable. Three defuzzifiers are used to control the actuators; cooler fan, water pump and r
Metal nanoclusters (NCs) have emerged as feasible alternatives to dyes and quantum dots in light energy conversion applications. Despite the remarkable enhancement in power conversion efficiency (PCE) in recent years and the increase in the number of NCs available as sensitizers, a comprehensive understanding of the various interfacial charge-transfer, transport, and recombination events in NCs is still lacking. This understanding is vital to the establishment of design principles for an efficie
The presence of alkali metal ions (AMIs) during the adsorption of thiolated Au nanoclusters (NCs) onto TiO2 plays a critical role in achieving high power conversion efficiency and suppressing anomalous current–voltage hysteresis in metal nanocluster-sensitized solar cells. This hidden role of the AMIs is intimately related to the adsorption strength between the NCs and TiO2, indicating the importance of seeking a comprehensive understanding of NC–TiO2 interfaces and devising interfacial engineer