Anodic SnO2 Nanoporous Structure Decorated with Cu2O Nanoparticles for Sensitive Detection of Creatinine: Experimental and DFT Study

Computational Modeling of Properties of Quantum Dots and Nanostructures: From First Principles to Artificial Intelligence (A Review)

Nanomaterials, including quantum dots, have gained more and more attention in the past few decades due to their extraordinary properties that make them useful for many applications, ranging from catalysis, energy generation and storage, biotechnology, and medicine to quantum informatics. Mathematical descriptions of the phenomena in which nanostructures are involved are of great demand because they may be utilized for the purpose of controlling these phenomena (e.g., the growth of nanostructures with certain sizes, shapes, and other properties). Such models may be of distinct nature, including calculations from first principles, ordinary and partial differential equations, and machine learning models (including artificial intelligence) as well. The aim of this article is to review the most important and useful computational and mathematical approaches for the description and control of processes involving nanostructures.

Effect of polishing on the morphology of Zircaloy-4 nanostructure: formation of a novel hexagonal nanoscale pattern

Zircaloy-4 (Zr-4) is widely used as the cladding material in nuclear power plants (NPPs) due to its excellent corrosion resistance and low neutron absorption cross-section. Under Loss of Coolant Accident (LOCA) conditions, oxidation of Zr-4 can compromise the safety of the NPPs by accelerating hydrogen production. Therefore, enhancing the oxidation resistance of Zr-4 is a critical research focus. Surface modification through a facile method offers a promising approach to address this issue. This study explores the impact of chemical, mechanical, and electropolishing (EP) pre-treatments on Zr-4 morphology before and after anodization. EP conducted in ethylene glycol monobutyl ether-perchloric acid electrolyte produced a mirror-like surface finish with hexagonal nanopattern formation under optimized conditions, as revealed by SEM studies. Anodization of the patterned surface in a glycerol-based electrolyte resulted in a hybrid (nanoporous and nanotubular) structure, unlike the nanotubular-only morphology observed in the chemically or mechanically polished samples. EDAX and XRD analyses confirmed the formation of ZrO2. The hexagonal nanopattern generated by EP suppressed the dissolution of the nanotube during anodization, resulting in a hybrid nanostructure. Additionally, the chemical polishing of EP-treated Zr-4 in HF : HNO3 : H2O generated a porous particulate structure due to selective etching. This work demonstrates that the surface pre-treatment significantly influences the morphology of anodized Zr-4 nanostructures and suggests the potential use of EP in other materials for hexagonal nanopattern generation.

Functionalizable poly-terthiophene/Cu2O heterojunction constructed in situ for sensitive photoelectrochemical detection of long non-coding RNA markers

A photoelectrochemical (PEC) sensor based on the poly-2,2,5,2-terthiophene (pTTh)/Cu2O heterojunction was constructed and applied for the detection of long non-coding RNA (lncRNA) TROJAN, a biomarker of triple-negative breast cancer. Cu2O and pTTh were electrodeposited in situ and sequentially onto an indium tin oxide substrate. The bandgap of the resultant type II heterojunction was measured spectroscopically and the morphology was found to effectively separate photogenerated holes from electrons. A photocurrent density as high as 250 μA cm-2 was attained, which is about three times higher than those of only pTTh or Cu2O. Owing to the close contact between pTTh and Cu2O, this PEC sensor is highly stable. Oligonucleotide probes for lncRNA can be cross-linked to carboxyl moieties of mercaptopropionic acid molecules adsorbed on pTTh/Cu2O. The desirable band structure and the high density of probe molecules collectively yielded a linear range of 0.1-10 000 pM. Our PEC sensor has been demonstrated to be amenable for detection of lncRNA markers with excellent analytical performance.

Ammonia oxidation by in-situ chloride electrolysis in etching wastewater of semiconductor manufacturing using RuSnOx/Ti electrode: Effect of plating mode and metal ratio

The indirect chloride-mediated ammonia oxidation encounters challenges in maintaining the effectiveness of metal oxide anodes when treating wastewaters with complex compositions. This study aims to develop a highly stable anode with RuO2-SnO2 coatings for treating an etching effluent from semiconductor manufacturing, which majorly contains NH3 and organic compounds. The RuSnOx/Ti electrode was synthesized using wet impregnation and calcination processes. The metal oxide configuration on Ti plate substrate was tuned by varying the step-dipping process in RuCl3 and SnCl4 baths. A 10-day continuous-flow electrolysis was conducted for studying the ammonia removal and chlorine yield under variable conditions, including detention, pH, current density, and initial ammonia and chloride concentrations. In the RuSnOx coatings, the configuration comprising RuO2 nanorods as the surface layer and an intermediate layer of SnO2 crystallites (by plating Ru3+ for three times to cover one Sn4+ layer, denoted as the Ru3Sn/Ti electrode) exhibited the best durability for acid washing, along with relatively high Faradaic efficiency and low energy consumption. To further improve the treatability of real wastewater (NH3-N = 634 mg L-1, chemical oxygen demand (COD) = 6700 mg L-1, Cl- = 2000 mg L-1, pH 11), the duel-cell electrolyzers were constructed in series under a current density of 30 mA cm-2 and 45 min detention. Ultimately, removals of NH3 and COD reached 95.8% and 76.3%, respectively, with successful limitation of chloramine formation.

Electrochemical Creatinine (Bio)Sensors for Point-of-Care Diagnosis of Renal Malfunction and Chronic Kidney Disorders

In the post-pandemic era, point-of-care (POC) diagnosis of diseases is an important research frontier. Modern portable electrochemical (bio)sensors enable the design of POC diagnostics for the identification of diseases and regular healthcare monitoring. Herein, we present a critical review of the electrochemical creatinine (bio)sensors. These sensors either make use of biological receptors such as enzymes or employ synthetic responsive materials, which provide a sensitive interface for creatinine-specific interactions. The characteristics of different receptors and electrochemical devices are discussed, along with their limitations. The major challenges in the development of affordable and deliverable creatinine diagnostics and the drawbacks of enzymatic and enzymeless electrochemical biosensors are elaborated, especially considering their analytical performance parameters. These revolutionary devices have potential biomedical applications ranging from early POC diagnosis of chronic kidney disease (CKD) and other kidney-related illnesses to routine monitoring of creatinine in elderly and at-risk humans.