Copper Thiocyanate Research Articles

Red-color-modulated perovskite solar cells with copper(I) thiocyanate/cellulose acetate–based distributed Bragg reflectors

Abstract This study investigates the development of perovskite solar cells (PSCs) equipped with distributed Bragg reflectors (DBRs) through a coating-based fabrication technique. The incorporation of DBRs enhanced the esthetic appeal and improved the light absorption properties of PSCs, rendering them suitable for building-integrated photovoltaics (BIPV). The DBRs, composed of 3–11 layers of copper(I) thiocyanate and cellulose acetate, exhibited peak reflectance at 700 nm. However, as the number of DBR layers increased, there was a corresponding decrease in short-circuit current density (Jsc) and power conversion efficiency (PCE) due to greater light reflection. Specifically, compared with PSCs without DBRs, those with 11-layer DBRs showed 41.2% and 39.0% reduction in Jsc and PCE, respectively. Despite these reductions, this study highlights the potential of colored PSCs for practical BIPV applications, achieving a balance between esthetics and efficiency.

Enhanced charge separation at the interface of Cu2O/CuSCN composite thin films synthesized by electrodeposition technique

This study focuses on the synthesis and characterization of hole transport layers (HTLs) for solar cells, par- ticularly copper(I) thiocyanate (CuSCN) and cuprous oxide (Cu2O), synthesized via electrodeposition tech- niques. CuSCN and Cu2O offer promising properties for efficient charge transport in photovoltaic devices. The synthesis processes involve precise control of deposition parameters to achieve desired film morpholo- gies and properties. Characterization techniques including scanning electron microscopy (SEM), atomic force microscopy (AFM), and ultraviolet-visible (UV-Vis) spectroscopy provide insights into film morphology and optical properties. Optimization of synthesis parameters for Cu2O films is explored to enhance their electrical properties. Photoelectric response measurements indicate improved charge separation at the interface of Cu2O/CuSCN composite films. These findings can contribute to the advancement of solar cell technology. Furthermore, the study extends its exploration to the fabrication of Cu2O by electrodeposition at different pH levels. SEM and X-ray diffraction (XRD) analyses reveal the impact of deposition parameters on film mor- phology and crystal structure, providing valuable insights for tailored synthesis approaches. Overall, this comprehensive study not only advances the understanding of HTL materials synthesis and optimization but also provides valuable guidance for the development of high-efficiency and stable solar cell devices.

Effects of Antisolvent Treatment on Copper(I) Thiocyanate Hole Transport Layer in n-i-p Perovskite Solar Cells.

Copper(I) thiocyanate (CuSCN) is considered an efficient HTL of low cost and with high stability in perovskite solar cells (PSCs). However, the diethyl sulfide solvent used for CuSCN preparation is known to cause damage to the underlying perovskite layer in n-i-p PSCs. Antisolvent treatment of CuSCN during spin-coating can effectively minimize interfacial interactions. However, the effects of antisolvent treatment are not sufficiently understood. In this study, the effects of five different antisolvents were investigated. Scanning electron microscopy and X-ray diffraction analyses showed that the antisolvent treatment improved the crystallinity of the CuSCN layer on the perovskite layer and reduced damage to the perovskite layer. However, X-ray and ultraviolet photoelectron spectroscopy analyses showed that antisolvent treatment did not affect the chemical bonds or electronic structures of CuSCN. As a result, the power conversion efficiency of the PSCs was increased from 14.72% for untreated CuSCN to 15.86% for ethyl-acetate-treated CuSCN.

Investigating the Mechanism of Triboluminescence: Insights from Structural and Electrostatic Characterization of Copper Thiocyanate Complexes.

Triboluminescence is a phenomenon in which light is generated through mechanical stress; it has emerging applications in stress-sensing devices. Although the prevailing mechanistic model indicates that light emits from charge separation and recombination in fracture planes arising from polar structures, its application in designing triboluminescent materials remains limited owing to numerous exceptions. This study provides insights into the essential requirements for triboluminescence by investigating the structural and electrostatic properties of fractured crystals of copper thiocyanate complexes. The examined fracture plane indicated that charge pairs (which are essential for light emission) form when intermolecular interactions are disrupted during fracturing. On the basis of the nature of these charges, we successfully suppressed triboluminescence by inhibiting the formation of intermolecular interactions disrupted in the examined complexes. Furthermore, we induced its re-emergence by creating an alternative fracture plane through controlled manipulation of the molecular network. This demonstrative deactivation and reactivation of triboluminescence underscores the critical role of intermolecular disruption in generating charge pairs, a prerequisite for triboluminescence.

Doping of Copper(I) Thiocyanate (CuSCN) with Metal Chlorides for p-Channel Thin-Film Transistors

Doping of Copper(I) Thiocyanate (CuSCN) with Metal Chlorides for p-Channel Thin-Film Transistors

Engineering middle transparent electrodes for enhanced performance of parallel tandem organic photovoltaics

Organic Photovoltaics (OPVs) have emerged as leading materials for next-generation energy sources. Despite the advancements in organic photoactive materials, research on parallel tandem organic photovoltaics (PT-OPVs) has been limited. The efficiency of PT-OPVs can be improved by reducing the difference in the open-circuit voltages (VOC) between the front and back subcells. However, there is a significant gap in research on the middle transparent electrode (MTE), which is crucial for achieving the desired energy-level alignment between the photoactive layers of these subcells and establishing electrical connectivity between them. This gap limits the utilization of reported high-performance photoactive materials in PT-OPV devices. To address this issue, a novel MTE is developed by depositing a copper (I) thiocyanate (CuSCN) hole transport layer on a molybdenum oxide/thin silver/molybdenum oxide (MAM) multilayer structure. The MAM/CuSCN MTE is distinguished by its higher work function and reduced surface roughness. As a result, integrating the MAM/CuSCN MTE in the PT-OPVs substantially increases the VOC of the back subcells (from 714 mV to 773 mV) while simultaneously minimizing the difference in VOC between the front and back subcells; thus, improving the performance of the device. Our findings provide valuable insights into the engineering of MTEs to enhance PT-OPVs' efficiency.

Co‐Solvent Assisted Optimization of the CuSCN Hole Transport Layer for Enhancing the Efficiency of Ambient Processable Perovskite Solar Cells with Carbon Counter Electrodes

In recent perovskite solar cell (PSC) research, copper(I) thiocyanate (CuSCN) is an emerging inorganic hole transport layer (HTL) due to its suitable band gap, matched band edge positions with the perovskite and high stability under ambient conditions. However, being a coordination polymer typically requires sulfide‐based solvents that strongly interact with Cu(I) for dissolution. Dipropyl sulfide (DPS) is generally used where it is very sparingly soluble of about 10–12 mg mL−1, which leads to low surface coverage with pin‐holes on the surface responsible for the generation of defects at the perovskite–HTL interface. In this study, addition of the optimized amount 100 μL of co‐solvent Acetonitrile (ACN) increased the CuSCN dissolution from 10 to 35 mg mL−1. ACN can act as a Lewis‐base making it capable of donating electrons to a Lewis‐acid like Cu+ from CuSCN. ACN is a polar aprotic solvent due to its highly polar CN bond and by adding CuSCN the dipole–dipole interactions can stabilize the CuSCN molecules in solution. The device with architecture (FTO/c‐TiO2/mp‐TiO2/MAPbI3/CuSCN/carbon) showed the higher power conversion efficiency (PCE) of ≈11% with Voc of 1.01 V and Isc 24.65 mA cm−2 showing excellent stability stored under ambient atmosphere which retains 80% of its initial efficiency after 10 days.

Accelerated de-chelation of EDTA-metal complexes: A novel and versatile approach for wastewater and solid waste remediation

Industrial waste, including wastewater and solid waste, often contains toxic heavy metals that necessitate extraction and separation prior to safe disposal or reusing them. Sewage sludge incineration ash (SSIA), a non-incinerable waste, holds significant amounts of heavy metals such as iron, zinc, copper, nickel, chromium, and lead. Recovery and reuse of heavy metals from SSIA and further application of treated SSIA sludge remain challenging. Ethylenediaminetetraacetic acid (EDTA) is widely used for heavy metals chelation in different applications. While its chelation with heavy metals is rapid and easy to achieve, the de-chelation of the metal complexes is otherwise slow (∼3 days) and challenging due to their high stability constants. In this study, we investigate the recovery of heavy metals from SSIA through chelation using EDTA, and develop, for the first time, a method to rapidly de-chelate the EDTA-metal complexes through the facile chilling process (1 – 3 h) that accelerates the separation of EDTA and metal ions. A sequential precipitation of high-purity heavy metals from the EDTA-metal complexes was demonstrated with and without de-chelation. This novel and versatile method allows the separation of many valuable compounds from the treated SSIA, including regenerated EDTA, potassium hexafluorosilicate, iron phosphate, iron(III) hydroxide, iron silicate, titanium phosphate, calcium phosphate, copper(I) thiocyanate, nickel bis(dimethylglyoximate), lead(II) sulfate, and zinc sulfide. This approach opens doors for more sustainable waste management and the recovery of valuable resources from industrial waste.

Semitransparent organic photovoltaics enabled by transparent p-type inorganic semiconductor and near-infrared acceptor

Semitransparent organic photovoltaics (STOPVs) have gained wide attention owing to their promising applications in building-integrated photovoltaics, agrivoltaics, and floating photovoltaics. Organic semiconductors with high charge carrier mobility usually have planar and conjugated structures, thereby showing strong absorption in visible region. In this work, a new concept of incorporating transparent inorganic semiconductors is proposed for high-performance STOPVs. Copper(I) thiocyanate (CuSCN) is a visible-transparent inorganic semiconductor with an ionization potential of 5.45 eV and high hole mobility. The transparency of CuSCN benefits high average visible transmittance (AVT) of STOPVs. The energy levels of CuSCN as donor match those of near-infrared small molecule acceptor BTP-eC9, and the formed heterojunction exhibits an ability of exciton dissociation. High mobility of CuSCN contributes to a more favorable charge transport channel and suppresses charge recombination. The control STOPVs based on PM6/BTP-eC9 exhibit an AVT of 19.0% with a power conversion efficiency (PCE) of 12.7%. Partial replacement of PM6 with CuSCN leads to a 63% increase in transmittance, resulting in a higher AVT of 30.9% and a comparable PCE of 10.8%.

Efficient and Stable CuSCN-based Perovskite Solar Cells Achieved by Interfacial Engineering with Amidinothiourea.

Cuprous thiocyanate (CuSCN) emerges as a prime candidate among inorganic hole-transport materials, particularly suitable for the fabrication of perovskite solar cells. Nonetheless, there is an Ohmic contact degradation between the perovskite and CuSCN layers. This is induced by polar solvents and undesired purities, which reduce device efficiency and operational stability. In this work, we introduce amidinothiourea (ASU) as an intermediate layer between perovskites and CuSCN to overcome the above obstacles. The characterization results confirm that ASU-modified perovskites have eliminated trap-induced defects by strong chemical bonding between -NH- and C═S from ASU and under-coordinated ions in perovskites. The interfacial engineering based on the ASU also reduces the potential barrier between the perovskite and CuSCN layers. The ASU-treated perovskite solar cells (PSC) with a gold electrode obtains an improved power conversion efficiency (PCE) from 16.36 to 18.03%. Furthermore, after being stored for 1800 h in ambient air (relative humidity (RH) = 45%), the related device without encapsulation maintains over 90% of its initial efficiency. The further combination of ASU and carbon-tape electrodes demonstrates its potential to fabricate low-cost but stable carbon-based PSCs. This work finds a universal approach for the fabrication of efficient and stable PSCs with different device structures.

Improvement of Thermal Stability and Photoelectric Performance of Cs2PbI2Cl2/CsPbI2.5Br0.5 Perovskite Solar Cells by Triple-Layer Inorganic Hole Transport Materials.

Conventional hole transport layer (HTL) Spiro-OMeTAD requires the addition of hygroscopic dopants due to its low conductivity and hole mobility, resulting in a high preparation cost and poor device stability. Cuprous thiocyanate (CuSCN) is a cost-effective alternative with a suitable energy structure and high hole mobility. However, CuSCN-based perovskite solar cells (PSCs) are affected by environmental factors, and the solvents of an HTL can potentially corrode the perovskite layer. In this study, a Co3O4/CuSCN/Co3O4 sandwich structure was proposed as an HTL for inorganic Cs2PbI2Cl2/CsPbI2.5Br0.5 PSCs to address these issues. The Co3O4 layers can serve as buffer and encapsulation layers, protecting the perovskite layer from solvent-induced corrosion and enhancing hole mobility at the interface. Based on this sandwich structure, the photovoltaic performances of the Cs2PbI2Cl2/CsPbI2.5Br0.5 PSCs are significantly improved, with the power conversion efficiency (PCE) increasing from 9.87% (without Co3O4) to 11.06%. Furthermore, the thermal stability of the devices is also significantly enhanced, retaining 80% of its initial PCE after 40 h of continuous aging at 60 °C. These results indicate that the Co3O4/CuSCN/Co3O4 sandwich structure can effectively mitigate the corrosion of the perovskite layer by solvents of an HTL and significantly improves the photovoltaic performance and thermal stability of devices.

The CuSCN layer between BiVO4 and NiFeOx for facilitating photogenerated carrier transfer and water oxidation kinetics

Modification of oxygen evolution co-catalyst (OEC) on the surface of bismuth vanadate (BiVO4) can effectively improve the kinetics of water oxidation, but it is still limited by the small hole extraction driving force at the BiVO4/OEC interface. Modulating the BiVO4/OEC interface with a hole transfer layer (HTL) is expected to facilitate hole transport from BiVO4 to the OEC surface. Herein, a copper(I) thiocyanate (CuSCN) HTL is inserted between BiVO4 and NiFeOx OEC to create BiVO4/CuSCN/NiFeOx photoanode, resulting in a significant enhancement of photoelectrochemical (PEC) water splitting performance. From electrochemical analyses and density functional theory (DFT) simulations, the markedly enhanced PEC performance is attributed to the insertion of CuSCN as an HTL, which promotes the extraction of holes from BiVO4 surface and boosts the water oxidation kinetics. The optimal photoanode achieves a photocurrent density of 5.6 mA cm−2 at 1.23 V versus the reversible hydrogen electrode (vs. RHE) and an impressive charge separation efficiency of 96.2 %. This work offers valuable insights into the development of advanced photoanodes for solar energy conversion and emphasizes the importance of selecting an appropriate HTL to mitigate recombination at the BiVO4/OEC interface.

Slot‐Die Deposition of CuSCN Using Asymmetric Alkyl Sulfides as Cosolvent for Low‐Cost and Fully Scalable Perovskite Solar Cell Fabrication

The development of industrially relevant deposition processes for efficient, stable, and inexpensive charge extracting layers is crucial for the commercialization of perovskite solar cells (PSCs). This work demonstrates, for the first time, the deposition of copper thiocyanate (CuSCN) as a low‐cost and reliable hole‐transport layer using slot‐die coating. Methyl ethyl sulfide is thereby used as an asymmetric cosolvent to significantly increase the solubility of CuSCN in the utilized slot‐die ink compared to traditional pure diethyl sulfide‐based solutions. Optimized CuSCN inks allow for the deposition of CuSCN layers on 5 × 10 cm2 substrates with a wide range of thicknesses. Multidimensional imaging photoluminescence techniques are used to investigate the uniformity of the CuSCN thin films deposition as well as the influence of the solvent on charge losses. Finally, the CuSCN slot‐die deposition is integrated into a fully upscalable PSC fabrication process showing 19.1% power conversion efficiency for small laboratory cells and 14.7% for 9 cm2 minimodules. Furthermore, semitransparent minimodules retain 80% of their initial efficiency after 500 h of constant illumination.

Efficient BiVO4 Photoanode with an Excellent Hole Transport Layer of CuSCN for Solar Water Oxidation

AbstractBismuth vanadate (BiVO4) is reported as a key material in photoelectrocatalysis owing to high theoretical efficiency, relatively narrow band gap of 2.4 eV, and favorable conduction band edge position for hydrogen evolution. However, the sluggish hole transport dynamics lead to slow photogenerated charge separation and transport efficiencies, which result in charge recombination due to aggregation. Herein, a novel hole transport layer of copper(I) thiocyanate (CuSCN) with the aim of significantly enhancing the efficiency of charge transport and stability of BiVO4 photoanodes is reported. The introduction of the hole transport layer could provide an appropriate intermediate energy level for photogenerated hole transfer and avoid charge recombination and trapping. After a photoassisted electrodeposition process of NiCoFe‐Bi catalysis, the obtained photoanode achieves a photocurrent density of 5.6 mA cm−2 at 1.23 V versus reversible hydrogen electrode under AM 1.5 G simulated solar radiation, and an applied bias photon to current efficiency of 2.31%. With the CuSCN layer, BiVO4 photoanode presented impressive stable photocurrent during 50 h continuous illumination. Meanwhile, the unbiased tandem device of the NiCoFe‐Bi/CuSCN/BiVO4 photoanode and the Si solar cell exhibit a solar‐to‐hydrogen efficiency of 5.75% and excellent stability for 14 h.

All-Inorganic Hydrothermally Processed Semitransparent Sb2S3 Solar Cells with CuSCN as the Hole Transport Layer.

An inorganic wide-bandgap hole transport layer (HTL), copper(I) thiocyanate (CuSCN), is employed in inorganic planar hydrothermally deposited Sb2S3 solar cells. With excellent hole transport properties and uniform compact morphology, the solution-processed CuSCN layer suppresses the leakage current and improves charge selectivity in an n-i-p-type solar cell structure. The device without the HTL (FTO/CdS/Sb2S3/Au) delivers a modest power conversion efficiency (PCE) of 1.54%, which increases to 2.46% with the introduction of CuSCN (FTO/CdS/Sb2S3/CuSCN/Au). This PCE is a significant improvement compared with the previous reports of planar Sb2S3 solar cells employing CuSCN. CuSCN is therefore a promising alternative to expensive and inherently unstable organic HTLs. In addition, CuSCN makes an excellent optically transparent (with average transmittance >90% in the visible region) and shunt-blocking HTL layer in pinhole-prone ultrathin (<100 nm) semitransparent absorber layers grown by green and facile hydrothermal deposition. A semitransparent device is fabricated using an ultrathin Au layer (∼10 nm) with a PCE of 2.13% and an average visible transmittance of 13.7%.

Review of Synthesis and Characterization of Cu (I) Complexes

d-block metals show great promise in inorganic catalytic research. Particularly, copper, d9 metal has contributed to catalytic properties of its complexes. A series of copper complexes was synthesized and structurally characterized. The copper (I) complexes of this series were investigated in regard to their reactivity towards dioxygen using stopped-flow techniques. For most complexes no “oxygen adduct” complexes as intermediates could be detected. In this article, some complexes of Cu (I) have been included and the ligands on which work had been done are mentioned below: 1,5-bis(benzimidazole-2-yl)-3-thiapentane Tridentate di-pyrazole -3,6-di-tert-butyl-carbazole (N, N, N-Pincer ligand) Methyl isocyanate N4Cu Tris(pyrazolyl) hydroborate ligand Scorpionate ligand Phenanthroline Tripodal amine ligands Triazole derivatives Keywords: BBES (1,5-bis(benzimidazole-2-yl)-3-thiapentane), MeIN (Methyl isocyanate), CuSCN (copper thiocyanate), PPh3(triphenyl phosphine), PCy3(tricyclohexyl phosphine), TptBuPh (tris[3-(p-tert-butylphenyl)], Tp (tris pyrazolyl hydroborate), Me4-p,3,3 (3,3-dimethylaminopropyl-(2-methylenpyridyl)-amine), Me2-pp3 (3-dimethylaminopropyl-bis(2-methylenpyridyl)-amine)

Thermally deposited copper(I) thiocyanate thin film: An efficient and sustainable approach for hole transport layer in perovskite solar cells

Solution-processable deposition of copper(I) thiocyanate (CuSCN) thin films have been widely used as hole transport layer (HTL) in optoelectronic applications, namely perovskite and organic solar cells. Herein, we report thermally...

A copper(I) thiocyanate-based photoresponsive semiconducting 2D coordination polymer.

A coordination polymer, [Cu(SCN)(iqi)]n (iqi = isoquinoline), containing copper(I) thiocyanate and a nitrogen-containing π-conjugated ligand, iqi, has been synthesized and its physical properties were evaluated. This coordination polymer has a two-dimensional (2D) sheet structure consisting of copper(I) thiocyanate and shows photoluminescence derived from 3MLCT and photoconductive properties.

Band gap engineering in pyridyl-functionalized two-dimensional (2D) CuSCN coordination polymers

3D CuSCN is transformed into 2D sheet structures when coordinated with pyridine (Py)-based ligands at a specific 1 : 1 ratio. By varying the substituent at the 3-position, the optical and electronic properties can be systematically tuned.

The fabrication of self-powered P-I-N perovskite photodetectors with high on-off ratio using cuprous thiocyanate as hole transport layer

The fabrication of self-powered P-I-N perovskite photodetectors with high on-off ratio using cuprous thiocyanate as hole transport layer