In this study, activated carbon derived from mangosteen peel (abbreviated as ACMP) was successfully fabricated. This as-prepared ACMP possessed graphite and had a porous structure with a specific surface area of 419.8554 m²/g. Investigations of the influencing factors on the ciprofloxacin (CIP) adsorption capability of the ACMP based on the static adsorption method showed that: adsorption equilibrium can be achieved in 60 min, the optimal pH for CIP adsorption was a pH of 6, and the optimal ratio between the material mass and solution volume was 3 g/L. The CIP adsorption process of the ACMP follows the Langmuir, Freundlich, Tempkin, Elovich, and Redlich–Peterson isotherm adsorption models. The maximum adsorption capacity calculated according to the Langmuir isothermal adsorption model for the CIP of the ACMP was (q_max = 29.76 mg/g). The CIP adsorption process of the ACMP followed the apparent quadratic kinetic equation, as well as spontaneous, endothermic, physical, and chemical adsorption. The adsorption rate was governed by membrane diffusion.

For the first time, activated carbon from a durian shell (ACDS) activated by H₂SO₄ was successfully synthesized in the present study. The fabricated ACDS has a porous surface with a specific surface area of 348.0017 m²·g⁻¹, average capillary volume of 0.153518 cm³·g⁻¹, the average pore diameter of 4.3800 nm; ash level of 55.63%; humidity of 4.74%; density of 0.83 g·cm⁻³; an iodine index of 634 mg·g⁻¹; and an isoelectric point of 6.03. Several factors affecting Methylene Blue (MB) adsorption capacity of ACDS activated carbon was investigated by the static adsorption method, revealing that the adsorption equilibrium was achieved after 90 min. The best adsorbent pH for MB is 7 and the mass/volume ratio is equal to 2.5 g·L⁻¹. The MB adsorption process of ACDS activated carbon follows the Langmuir, Freundlich, Tempkin, and Elovich isotherm adsorption model, which has determined the maximum adsorption capacity for MB of ACDS as q_max = 57.47 mg·g⁻¹. The MB adsorption process of ACDS follows the of pseudo-second-order adsorption kinetic equation. The Weber and Morris Internal Diffusion Model, the Hameed and Daud External Diffusion Model of liquids have been studied to see if the surface phase plays any role in the adsorption process. The results of thermodynamic calculation of the adsorption process show that the adsorption process is dominated by chemical adsorption and endothermic. The obtained results provide an insight for potential applications of ACDS in the treatment of water contaminated by dyes.

The choice of precursor and simple synthesis techniques have decisive roles in the viable production and commercialization of carbon products. The intense demand for developing high-purity carbon nanomaterials through inexpensive techniques has promoted the usage of fossil derivatives as a feasible source of carbon. In this study, Vietnamese-coal-derived porous carbon (PC) was used to fabricate coal-derived porous carbon nanomaterials (CDPCs) using the modified Hummers method. The resulting porous carbon nanomaterials achieved a nanoscale structure with an average pore size ranging from 3 to 10 nm. The findings indicate that CDPC exhibits well-developed micropores and mesopores. The presence of macropores and mesopores not only facilitates the complete immersion of the material in the electrolyte but also effectively shortens the ion diffusion pathways. CDPC boasts a high carbon content, constituting 80.88% by weight. Electrochemical impedance spectroscopy (EIS) Nyquist plot of electrodes made from CDPC showed good conductivity value with low charge-transfer resistance. This electrode worked well and stably with capacitance retention of 74.7% after 1000 cycles. The CDPC specific capacitance reached 236 F/g under a current density of 0.1 A using the constant current discharge method and then decreased as the current density increased. Based on the results of the electrochemical properties of the materials, the energy storage capacity of the CDPC material was good and stable. This investigation presents an eco-friendly methodology for the judicious utilization of coal in energy storage applications, specifically as electrodes for supercapacitors and anodes for Li-ion batteries.

The ciprofloxacin (CIP) removal ability of a Fe-Cu electrolytic material was examined with respect to pH (2–9), time (15–150 min), shaking speed (100–250 rpm), material mass (0.2–3 g/L), temperature (298, 308, 323) and initial CIP concentration (30–200 mg/L). The Fe-Cu electrolytic materials were fabricated by the chemical plating method, and Fe-C materials were mechanically mixed from iron powder and graphite. The results show that at a pH value of 3, shaking time 120 min, shaking speed 250 rpm, a mass of Fe-Cu, Fe-C material of 2 g/L and initial CIP concentration of 203.79 mg/L, the CIP removal efficiency of Fe-Cu material reached 90.25% and that of Fe-C material was 85.12%. The removal of CIP on Fe-Cu and Fe-C materials follows pseudo-first-order kinetics. The activation energy of CIP removal of Fe-Cu material is 14.93 KJ/mol and of Fe-C material is 16.87 KJ/mol. The positive ΔH proves that CIP removal is endothermic. A negative entropy of 0.239 kJ/mol and 0.235 kJ/mol (which is near zero and is also relatively positive) indicated the rapid removal of the CIP molecules into the removed products.

Nghiên cứu này đã chế tạo vật liệu nano carbon PC (porous carbon) từ than đá anthracite Vàng Danh, Quảng Ninh bằng phương pháp thủy nhiệt kết hợp hoạt hóa ZnCl2. Vật liệu xốp, kích thước 10-20 nm, diện tích bề mặt riêng là 510 m2/g, hàm lượng C chiếm 80,59 %, O chiếm 14,13% về khối lượng. Nghiên cứu đã lựa chọn tỉ lệ vật liệu nano carbon xốp : graphite : carbon nanotube : Polyme Polyvinylidene fluoride (PVDF) bằng 70:10:10:10, lực ép 5 tấn, nhiệt độ sấy điện cực 250 oC tối ưu cho quá trình chế tạo điện cực anode. Dung dịch LiPF6 1M pha trong dung môi theo tỷ lệ về thể tích EC: DEC : DMC bằng 1:1:1 có trong thành phần của điện cực đã giảm sự mất khối lượng của điện cực và tăng khả năng chống cháy nổ của điện cực. Kết quả nghiên cứu cho thấy điện cực PC làm việc tốt, ổn định với khả năng duy trì điện dung là 55,65 % sau 900 chu kỳ.

Tổng hợp xanh nano bạc (AgNPs) sử dụng dịch chiết thực vật đã được nghiên cứu rộng rãi nhằm ứng dụng để phát hiện màu các ion kim loại và hoạt tính kháng khuẩn. Trong công bố này, nano bạc được tổng hợp sử dụng dịch chiết thân cây Trầu rừng, ứng dụng để phát hiện màu ion Fe3+. Cấu trúc và hình thái của AgNPs hình thành được xác định bằng phổ UV-Vis, FTIR, Raman, XRD và SEM. Nano bạc có dạng hình cầu, được bền hoá bởi các hợp chất hữu cơ có trong dịch chiết thân cây Trầu rừng, có kích thước khoảng 4-17 nm. Khả năng phát hiện ion Fe3+ của AgNPs được xác định bằng phổ UV-Vis. Các hạt nano bạc có thể dùng để phát hiện màu ion Fe3+ có độ chọn lọc, độ nhạy cao và độ bền tốt với giá trị LOD và LOQ lần lượt bằng 0,372 mM và 1,244 mM. Nồng độ Fe3+ trong mẫu nước sinh hoạt là 30,0 mM. Kết quả này khẳng định có thể sử dụng dịch chiết thân cây Trầu rừng để tổng hợp nano bạc và ứng dụng để phát hiện ion Fe3+ trong mẫu thực. Hơn nữa, AgNPs cũng thể hiện hoạt tính kháng khuẩn tốt.