Atiek Rostika Noviyanti

β‐Borylation of α,β‐unsaturated carbonyl compounds is a valuable strategy for preparing β‐borylated carbonyl derivatives that combine carbonyl reactivity with the synthetic versatility of carbon–boron bonds. This review summarizes recent advances in transition‐metal‐catalyzed and metal‐free β‐borylation, with emphasis on catalyst design, mechanisms, substrate scope, and synthetic utility. Platinum and rhodium systems provided early mechanistic foundations, while copper catalysis has become the most practical and broadly developed platform. Nickel, gold, and iridium catalysts offer complementary reactivity, including ester‐ and amide‐selective borylation, heterogeneous B–B/Si–B activation, and vinylic C–H borylation. Metal‐free approaches based on N‐heterocyclic carbenes, Brønsted base/alcohol systems, and phosphines further expand the activation modes of diboron reagents. Selected examples of Suzuki–Miyaura cross‐coupling, oxidation, fluorination, organotrifluoroborate stabilization, and one‐pot transformations highlight the synthetic potential of β‐borylated carbonyl intermediates. Current limitations and future opportunities in product stability, substrate generality, stereochemical transfer, and post‐borylation functionalization are also discussed.

The use of non-edible oil as a raw material and the use of biomass waste as a catalyst in the biodiesel production process is a strategic step due to the various advantages it offers. Palm acid oil (PAO), which is a waste from the palm oil processing industry, has great potential to be used as a raw material in biodiesel production, while rice husks can be processed and their properties modified to be used as a catalyst in the biodiesel formation reaction. This study aims to determine the characteristics and catalytic performance of sulfonated activated carbon from rice husks in the synthesis of biodiesel from PAO. Biodiesel was synthesized at various molar ratios of PAO to methanol of (1:16), (1:24), and (1:32). The reaction was carried out at a temperature of 65°C for 2 hours, with catalyst levels varied at 2, 3, and 5%. The results of the study showed that the best catalytic performance of sulfonated rice husk activated carbon in the synthesis of biodiesel from PAO was achieved at a mole ratio of PAO to methanol of (1:32) and a catalyst content of 2%. Under these synthesis conditions, the highest degree of conversion of free fatty acids into biodiesel was achieved, namely 85.08%, and biodiesel was produced with a yield of 99.20%. Further quality parameter testing of the biodiesel obtained density, kinematic viscosity, acid number, iodine number, cetane number, total glycerol content, and methyl ester content of biodiesel were 861.12 kg/m3, 5.38 mm2/s, 2.88 mg KOH/g, 63.45 g I2/100 g, 62.51, 0.29%, and 95.37%, respectively.

Background: Urea fertilizer is the primary nitrogen source in agriculture, but its conventional use often leads to significant nitrogen loss through leaching and volatilization. To address this issue, a slow-release fertilizer system is required to regulate nutrient delivery. Nanohydroxyapatite (nHA), a biocompatible inorganic material, can bind nutrients, while activated carbon (AC) offers high surface area and porosity, supporting controlled urea release. This study investigated the effect of mechanochemical ball milling on a previously developed nHA-AC composite for slow-release urea applications. Results: The composites were synthesized by varying the milling speeds (100, 150, and 200 rpm) for 30 min to examine the effect of speed on the composite properties. The optimum milling speed speed was subsequently applied while varying the milling duration (10, 20, and 30 min). The resulting composites were characterized and evaluated for urea adsorption and release performance. The composite synthesized at 200 rpm for 10 min exhibited a relatively high specific surface area (148.94 m ² /g), the most negative zeta potential (-38.0 mV), the highest adsorption capacity (Qt = 0.8932 g urea/g composite), and the slowest observed urea release among the evaluated composites (399.7 µg urea/min, corresponding to 10.7% release within 240 min). Conclusions: This study investigates the effect of mechanochemical ball milling conditions on the physicochemical properties, urea adsorption, and release behavior of the nHA-AC composites. Comparison with the previously reported unmilled nHA–AC composite prepared from the same precursor provides contextual evidence of improved adsorption performance following ball milling; however, this comparison does not constitute a direct experimental control because the unmilled material was not evaluated in parallel in the present study. The composite prepared at 200 rpm for 10 min showed the most favorable urea adsorption and release characteristics among the composites evaluated, supporting its potential for further investigation as a carrier for slow-release fertilizer applications.

Perovskite solar cell (PSC) performance is critically limited by surface defects and interfacial energy losses at the tin oxide (SnO₂) electron transport layer (ETL). This study investigates the surface modification of SnO₂ using cesium iodide (CsI) and cesium fluoride (CsF) to understand their influence on perovskite crystallization and interfacial carrier dynamics. Photovoltaic characterization reveals that the device response is strongly dependent on the chosen halide. Modification with CsI significantly enhances device performance, achieving a champion power conversion efficiency (PCE) of 21.77%, compared to 20.13% for the pristine baseline and 17.05% for the CsF-treated device. The superior performance of the CsI-modified device is driven by reduced trap density and an order of magnitude increase in carrier mobility. Structural and spectroscopic analyses demonstrate that CsI effectively passivates oxygen vacancies via strong interfacial electronic interactions, extending the bulk carrier lifetime to 34.96 ns and promoting the growth of highly compact perovskite crystals with larger domains (30.0 nm) and minimized dislocation density. Furthermore, an analysis of ambient-processing effects clarifies an inherent trade-off between short-circuit current density and fill factor (FF). These results establish that tailored halide engineering of the ETL surface is an effective strategy for mitigating interfacial recombination and advancing high-performance PSCs.

1. The widespread consumption of pharmaceuticals has resulted in the detection of drugs in natural waters and wastewaters as emerging contaminants posing health and ecological risks (1). Analgesic ...

Thermodynamically, hydroxyapatite (HAp) is highly stable in physiological fluid conditions, including pH, temperature and composition.1, 2 It is non-corrosive, non- toxic and bioactive.3 HAp has be...

Lithium-ion batteries require separators with high thermal stability and efficient ion transport to mitigate safety risks associated with thermal runaway. In this study, a hierarchically structured composite separator consisting of hydroxyapatite nanowires (HA NW) and ramie-derived cellulose fibers was fabricated through a solvothermal-assisted self-assembly approach. The influence of HA NW content on the structural, physicochemical, and electrochemical properties of the separator was systematically investigated. Among the prepared samples, HA NW/SS-3 with a HA NW-to-cellulose ratio of 30:70 exhibited the most balanced performance. The separator formed a three-dimensional interconnected porous network with a high porosity of 95.3% and excellent electrolyte wettability, enabling efficient electrolyte uptake and ion transport. Thermal shrinkage tests revealed outstanding dimensional stability, with only 5.05% shrinkage at 200 °C, whereas a commercial polypropylene separator exhibited severe shrinkage of approximately 98% under identical conditions. Electrochemical characterization demonstrated an ionic conductivity of 2.67 mS cm⁻1 and a lithium-ion transference number of 0.55, indicating favorable lithium-ion transport through the composite membrane. When evaluated in LiFePO4 half-cells, the separator delivered a discharge capacity of 138.37 mAh g⁻¹, confirming its capability to support stable battery operation. These findings demonstrate that the synergistic integration of thermally robust hydroxyapatite nanowires and sustainable cellulose fibers provides a promising separator architecture capable of simultaneously enhancing battery safety and electrochemical performance.