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Groundwater highly contaminated with organic substances and heavy metal ions in the Kariangau Industrial Area, Balikpapan, East Kalimantan is indicated by the comparatively high COD. Therefore, the technology for treating wastewater to remove various toxins before releasing it into the environment needs to be advanced. Here, we present a green synthetic method of a composite adsorbent (SF/SS) using soursop seeds and silkworm cocoons. SEM, FTIR, and BET were used to analyze the physicochemical characteristics of the adsorbent. Mechanistic investigation of the SF/SS adsorbent performance for the removal of Cu2+ metal ions and crystal violet (CV) was conducted, while taking into account variables affecting adsorption properties. The Freundlich and Langmuir isotherm adsorption models were used to fit the adsorption equilibrium, while pseudo-first and second-order models were used to assess the adsorption kinetics. The mesoporous SF/SS adsorbent exhibited the highest adsorption capacities of 78.6 and 69.2 mg-g-1, respectively. The pseudo-first model showed the best fit for CV removal with a kinetic rate of 0.0634 min-1, while the Freundlich model exhibited the best fitting for both of CV and Cu2+ removal. The results showed that SF/SS can be applied as an efficient adsorbent for both of heavy metal and organic dye removal. [ABSTRACT FROM AUTHOR]

Cyclometalated Iridium(III) complexes, i. e. [Ir(C N)2(dppz)][PF6], bearing either two or four ‐CH2PO(OH)2 anchoring groups (IrP2dppz or IrP4dppz) are explored as photosensitizers for p‐type dye sensitized solar cell (DSSC). The synthetic route is described and the iridium(III) complexes are characterized with respect to their electrochemical and photophysical properties. The modified anchoring ligand geometry exploited in this work not only alters the electronic nature of the complex (that is by destabilizing the LUMO energetically) but more importantly improves the grafting ability of the complex towards the NiO surface. The photoinduced long‐lived charge separated state (CSS) at the NiO|IrPxdppz interface is of a different nature comparing the two complexes. For IrP2dppz and IrP4dppz the electron density of the CSS dominantly resides on the dppz and the C N ligand, respectively. The stability of the CSS can be correlated to the solar cell performance in NiO‐based p‐DSSCs, which yield conversion efficiencies which are among the highest in the class of iridium(III) complexes developed for p‐DSSCs. [ABSTRACT FROM AUTHOR]

Annealing treatment was applied to different mesoporous ZnO nanostructures prepared by wet chemical synthesis, i.e. nanoflowers (NFs), spherical aggregates (SPs), and nanorods (NRs). The sub-bandgap, defect properties as well as the trapping state characteristics after annealing were characterized spectroscopically, including ultrasensitive photothermal deflection spectroscopy (PDS), photoluminescence and photo-electrochemical methods. The comprehensive experimental analysis reveals that annealing alters both the bandgap and the sub-bandgap. The defect concentration and the density of surface traps in the ZnO nanostructures are suppressed upon annealing as deduced from photoluminescence and open-circuit voltage decay analysis. The photo-electrochemical investigations reveal that the surface traps dominate the near conduction band edge of ZnO and, hence, lead to high recombination rates when used in DSSCs. The density of bulk traps in ZnO SPs is higher than that in ZnO NFs and ZnO NRs and promote lower recombination loss between photoinjected electrons with the electrolyte-oxidized species on the surface. The highest power conversion efficiency of ZnO NFs-, ZnO SPs-, and ZnO NRs-based DSSC obtained in our system is 2.0, 4.5, and 1.8%, respectively. [ABSTRACT FROM AUTHOR]

A series of thiocyanate-free bis(tridentate) ruthenium(II) complexes incorporating 1,2,3-triazole-derived NNN-, NCN-, and CNC-coordinating ligands has been employed for sensitizing ZnO photoanodes for dye-sensitized solar cells (DSSCs). Additionally, the first use of the TEMPO+/TEMPO (2,2,6,6-tetramethyl-piperidine-1-oxyl) redox mediator as a surrogate for the I3−/I− redox couple in ZnO nanostructured DSSCs is presented. Compared with I3−/I−-based electrolytes, shorter charge lifetimes and diffusion lengths were determined for the TEMPO+/TEMPO-based electrolyte. Nonetheless, similar power conversion efficiencies (PCEs) were achieved with both electrolytes for the RuNCN and RuCNC complexes, whereas higher PCEs are enabled by the iodine-free electrolyte in case of RuNNN. The combination of the molecular sensitizers and the TEMPO-based electrolyte exhibits relatively high external quantum efficiency (EQE) and promising PCEs, ranging from 4.48 to 1.47 %, which are-in part-comparable to that of ZnO-DSSCs with the benchmark N749 black dye. The TEMPO-based electrolyte also exhibits less absorption compared with its I3−/I− counterpart, a favorable feature for enhancing the light harvesting ability of the photoanode. Furthermore, the results show the effect of the dye-sensitization procedure on the PCE values: The use of ethanol as the solvent compared with methanol increases the DSSC's efficiency, which is attributed to improved chemisorption of the sensitizer onto the ZnO surface. [ABSTRACT FROM AUTHOR]

The Hybrid Electrical Energy Storage System (HESS) with supercapacitors in "GESITS" electric motorcycle offers greater power density and cycle life as well as a wider operating temperature range compared to batteries so as to maximize the existing regenerative braking features. In this study, the Four Switch Buck Boost Converter (FSBB) with Power Transfer is used as a current regulator to connect HESS. Fuzzy PID control is used to regulate the current that passes through the power transfer so that the braking force can be controlled based on the brake pull variable, vehicle speed and SOC supercapacitor. The results of the fuzzy control test with the MATLAB Fuzzy Designer obtained an average error of 1.44 %. While the results of the ITAE PID tuning method obtained a rise time of 3.33 seconds, a settling time of 3.11 seconds, an overshoot of 9.20 % and a steady state error of 2.20 %. From the results of the regenerative mode test, when given an input of 28-4 VDC, the average output voltage is 16.34 VDC with an average current of 8 A. While in the drive mode test with 28 VDC input, the average output voltage is 23.98 VDC and average current is 3.99 A with FSBB efficiency of 90.54 %. [ABSTRACT FROM AUTHOR]

[Display omitted] • The conjugated linker lowers the energy of the accepting orbitals in Rudppz complexes. • The extended bpy ligands in Rudppz destabilize the charge-separated state (CSS). • The CSS stability correlates with the electron transfer density in solar cells. We report on the localization of the initially excited electronic state within the molecular framework of a series of [Ru(bpy) 2 dppz]2+ derivatives (bpy:2,2′-bipyridine, dppz: dipyrido-phenazine) as sensitizers in NiO based photocathodes. The introduction of conjugated linkers with phenylene and triazole moieties in the bpy ligand sphere separates the NiO surface from the metal center and hence is considered to stabilize the charge separated state, which results from light-driven hole injection. However, introduction of the conjugated linkers also alters the localization of the excess electron density in the excited state within the ligand sphere and impacts the extent to which the charge-separated state is formed. The study emphasizes that tuning the ligand with the lowest-energy π* orbital distal or proximal to the NiO surface significantly affects the initial charge-separation and the solar cell performance. The stability of the charge-separated state correlates with the observed photocurrents in dye-sensitized solar cells. Furthermore, the study challenges the widely accepted concept that the introduction of extended anchoring groups, i.e. increasing Ru – NiO distance, stabilizes the charge-separated state and suppresses charge recombination at the metal-oxide molecule interface. [ABSTRACT FROM AUTHOR]

The cover picture shows a ZnO nanoflower with RuII complex bearing a 1,2,3‐triazole‐derived N C N cyclometalated ligand. Toward dye‐sensitized solar cells (DSSCs) free from iodine and thiocyanate, TEMPO+/TEMPO electrolyte in combination with RuII complexes bearing 1,2,3‐triazole‐derived N N N‐, N C N‐, and C N C‐coordinating ligands show promising power conversion and external quantum efficiencies in ZnO‐based DSSCs. Details are given in the Full Paper by B. Dietzek et al. on page 1281 in Issue 12, 2016 (DOI: 10.1002/cplu.201600377). [ABSTRACT FROM AUTHOR]

The development of p-type dye-sensitized solar cells (p-DSSCs) offers an opportunity to assemble tandem photoelectrochemical solar cells with higher efficiencies than TiO2-based photoanodes, pioneered by O'Regan and Grätzel [Nature 353, 737–740 (1991)]. This paper describes an investigation into the behavior at the interfaces in p-DSSCs, using a series of BODIPY dyes, BOD1-3. The three dyes have different structural and electronic properties, which lead to different performances in p-DSSCs. We have applied photoelectron spectroscopy and transient absorption spectroscopy to rationalize these differences. The results show that the electronic orbitals of the dyes are appropriately aligned with the valence band of the NiO semiconductor to promote light-induced charge transfer, but charge-recombination is too fast for efficient dye regeneration by the electrolyte. We attribute this fast recombination, which limits the efficiency of the solar cells, to the electronic structure of the dye and the presence of Ni3+ recombination sites at the NiO surface. [ABSTRACT FROM AUTHOR]

Cuprous oxide (Cu2O) was synthesized for the first time via an open bipolar electrochemistry (BPE) approach and characterized in parallel with the commercially available material. As compared to the reference, Cu2O formed through a BPE reaction demonstrated a decrease in particle size; an increase in photocurrent; more efficient light scavenging; and structure-correlated changes in the flat band potential and charge carrier concentration. More importantly, as-synthesized oxides were all phase-pure, defect-free, and had an average crystallite size of 20 nm. Ultimately, this study demonstrates the impact of reaction conditions (e.g., applied potential, reaction time) on structure, morphology, surface chemistry, and photo-electrochemical activity of semiconducting oxides, and at the same time, the ability to maintain a green synthetic protocol and potentially create a scalable product. In the proposed BPE synthesis, we introduced a common food supplement (potassium gluconate) as a reducing and complexing agent, and as an electrolyte, allowing us to replace the more harmful reactants that are conventionally used in Cu2O production. In addition, in the BPE process very corrosive reactants, such as hydroxides and metal precursors (required for synthesis of oxides), are generated in situ in stoichiometric quantity, providing an alternative methodology to generate various nanostructured materials in high yields under mild conditions. [ABSTRACT FROM AUTHOR]