Flower-like Nanosheets Research Articles

Performance study of bimetallic Mn-Zn porous flower-like nanosheets as supercapacitor positive electrode materials

As environmental and carbon emission issues become increasingly severe, electrochemical energy storage systems have gained attention. Compared to traditional supercapacitors, zinc-ion hybrid capacitors (ZIHCs) are not only environmentally friendly but also cost-effective. MnO2, with its low cost, eco-friendliness, high theoretical capacity, and stable crystal structure, is considered a promising positive electrode material. In this study, the morphology of MnO2 was optimized using electrodeposition. During cycling, zinc ions reversibly intercalate and extract from MnO2, forming a cactus-like nanoflower structure. This structure is loose and porous, providing ample reaction space for active materials. The assembled device exhibits excellent performance in both energy density (85.68 Wh kg−1) and stability (91.60 %).

Synthesis of a 3D Flower-Like BiOCl/Bi-MOF Heterostructure for High-Performance Removal of Rhodamine B and Tetracycline Hydrochloride.

Semiconductor materials based on bismuth metal have been extensively explored for their potential in photocatalytic applications owing to their distinctive crystal structure. Herein, we present the development of a hybrid photocatalyst, CAU-17/BiOCl, featuring a flower-like nanosheet morphology tailored for the photocatalytic degradation of organic contaminants such as rhodamine B (RhB) and tetracycline hydrochloride (TCH). The composite material is obtained by growing thin CAU-17 layers directly onto the host flower-like BiOCl nanosheets under solvothermal conditions. The optimized CAU-17/BiOCl composite possesses excellent photocatalytic performance, achieving a notable 96.0% removal rate for RhB and 78.4% for TCH after 60 and 90 min of LED light irradiation, respectively. This boosted activity is attributed to the heightened absorption of visible light caused by BiOCl and the provision of additional reaction sites due to the thin CAU-17 layers. Furthermore, the establishment of an S-scheme heterojunction mechanism enables efficient charge separation between CAU-17 and BiOCl, facilitating the separation of photoinduced electrons (e-) and holes (h+). Analysis of the degradation mechanism of RhB and TCH reveals the predominant role of superoxide radicals (•O2-), e-, and h+ in the photocatalytic degradation process. Moreover, the removal efficiency of TCH can reach approximately 64.5% after four cycles of recycling of CAU-17/BiOCl. Our work provides a facile, effective solution and a theoretically explained approach for the effective degradation of pollutants using heterojunction photocatalysts.

Pt─O Bond Accelerated Cu0/Cu+ Activity for Boosting Low-Energy Bipolar Hydrogen Production.

To address the imperative challenge of producing hydrogen in a low-energy consumption electrocatalytic system, this study emphasizes the utilization of thermodynamically favorable biomass oxidation for achieving energy-efficient hydrogen generation. This research integrates ultralow PtO2-loaded flower-like nanosheets (denoted as PtO2@Cu2O/Cu FNs) with Cu0/Cu+ pairs and Pt─O bonds, thereby yielding substantial enhancement in both hydrogen evolution reaction (HER, -0.042 VRHE at 10mAcm-2) and furfural oxidation reaction (FFOR, 0.09 VRHE at 10mAcm-2). As validated by DFT calculations, the dual built-in electric field (BIEF) is elucidated as the driving force behind the enhanced activities, in which Pt─O bonds expedite the HER, while Cu+/Cu0 promotes low-potential FFOR. By coupling the FFOR and HER together, the resulting bipolar-hydrogen production system requires a low power input (0.5072kWhperm3) for producing H2. The system can generate bipolar hydrogen and high value-added furoic acid, significantly enhancing hydrogen production efficiency and concurrently mitigating energy consumption.

Development of Ternary Layered Double Hydroxide Oxygen Evolution Reaction Electrocatalyst for Anion Exchange Membrane Water Electrolysis

To achieve net zero emissions, green hydrogen should be produced via water electrolysis with renewable energy. To develop efficient anion exchange membrane water electrolyzers (AEMWE), the development of efficient and stable non-precious metal electrocatalysts for the oxygen evolution reaction (OER) is essential. In this study, a high-performance ternary NiFeCo-layer double hydroxide (LDH) electrocatalyst for AEMWE was easily developed by the co-precipitation method. The introduction of Co has been shown to have an effect on the electronic structure of Ni and Fe, improving their intrinsic OER properties. In addition, the three-dimensional flower-like nanosheet morphology improved mass transfer and achieved excellent current density at high voltages. The ternary NiFeCo-LDH electrocatalyst requires low overpotentials (253 mV at 10 mA cm<sup>-2</sup>) and Tafel slope (45 mV dec<sup>-1</sup>) in 1 M KOH. AEMWE using the ternary NiFeCo-LDH electrocatalyst showed excellent electrolysis performance with a high current density of 2.27 A cm<sup>-2</sup> at 1.8 V cell. Moreover, an energy conversion efficiency of 86.73 % was achieved during the durability test for 100 hours at a current density of 0.5 A cm<sup>-2</sup>. The performance of the AEMWE electrolyzer utilizing the ternary NiFeCo-LDH electrocatalyst surpassed that of previously reported AEMWE electrolyzers. This work reports a highly active OER electrocatalyst that could open numerous opportunities for the development of ternary LDH electrocatalysts in AEMWE.

Anti-humidity and high sensitivity sensor for detecting acetone with Ce–ZnO nanosheets

Here, Ce-doped ZnO flower-like nanosheets are prepared by one-step hydrothermal method. The sensor based on Ce–ZnO composite exhibits excellent gas-sensing properties to acetone. Compared with pure ZnO, the response of Ce–ZnO composite is increased by 5.5 times, and the optimum operating temperature is reduced by 60 °C. The gas-sensing properties of the sensor to acetone under different humidity conditions are investigated. The redox reaction of Ce element increases the anti-humidity of Ce–ZnO sensor. Finally, the gas sensing mechanism of Ce–ZnO nanomaterial and anti-humidity principle are discussed in detail. The result can provide a new material for develop high sensitivity acetone sensor and a new anti-humidity strategy for designing gas sensing materials.

Nanoflower-like Ag adhered NiMo(OH)x composite arrays on nickel foam for high-performance supercapacitor

As the core component of supercapacitors, the choice of electrode material is critical in determining the energy and power density of the supercapacitors. To date, transition metal materials have been widely employed as electrodes in supercapacitors. In this study, we successfully designed and fabricated nanoflower-like Ag-NiMo(OH)x composite materials on a nickel foam base using a combination of hydrothermal and calcination techniques. NiMoOx flower-like nanosheets grown on NF increase the overall specific surface area of the electrode material and improve charge transport, provide mechanical stability, and supporting template for Ag nanoparticles attachment in the next step. With the solvothermal method, we are able to generate Ag nanoparticles onto NiMoOx nanosheets to obtain Ag-NiMo(OH)x. Utilizing the Ag-NiMo(OH)x composite as the cathode which displayed distinguished electrochemical performance with a specific capacity of 3548 mF cm−2 at 2 mA cm−2. We also construct solid-state asymmetric supercapacitors (ASCs) with Ag-NiMo(OH)x/NF electrode as the cathode and activated carbon electrode as the anode. The two-electrode system was analyzed, and the energy density achieved is 80.21 Wh kg−1 under 717.98 W kg−1. Furthermore, 84.66 % of the original capacity is left over after 10,000 charge-discharge cycles, indicating good cycling stability of the material.

Highly Efficient Cobalt Sulfide Heterostructures Fabricated on Nickel Foam Electrodes for Oxygen Evolution Reaction in Alkaline Water Electrolysis Cells

Non-noble metal electrocatalysts for the oxygen evolution reaction (OER) have recently gained particular attention. In the present work, a facile one-step electrodeposition method is applied in situ to synthesize cobalt sulfide nanostructures on nickel foam (NF) electrodes. For the first time, a systematic study is carried out on the impact of the Co/S molar ratio on the structural, morphological, and electrochemical characteristics of Ni-based OER electrodes by employing Co(NO3)2·6 H2O and CH4N2S as Co and S precursors, respectively. The optimum performance was obtained for an equimolar Co:S ratio (1:1), whereas sulfur-rich or Co-rich electrodes resulted in an inferior behavior. In particular, the CoxSy@NF electrode with Co/S (1:1) exhibited the lowest overpotential value at 10 mA cm−2 (0.28 V) and a Tafel slope of 95 mV dec−1, offering, in addition, a high double-layer capacitance (CDL) of 10.7 mF cm−2. Electrochemical impedance spectroscopy (EIS) measurements confirmed the crucial effect of the Co/S ratio on the charge-transfer reaction rate, which is maximized for a Co:S molar ratio of 1:1. Moreover, field emission scanning electron microscopy (FE-SEM), X-ray diffraction (XRD) and X-ray fluorescence (XRF) were conducted to gain insights into the impact of the Co/S ratio on the structural and morphological characteristics of the electrodes. Notably, the CoxSy@NF electrocatalyst with an equimolar Co:S ratio presented a 3D flower-like nanosheet morphology, offering an increased electrochemically active surface area (ESCA) and improved OER kinetics.

Controllable synthesis and PL propertiesof ZnO flower-like nanostructures by chemical bath method

Zinc oxide (ZnO) flower-like nanosheets and nanorods were synthesized on a glass substrate with an Al layer by a simple chemical bath method, and their morphology was controlled by adjusting the pH of the solution without the assistance of an additional surfactant. For the 3D nanostructures of the annealed nanosheets, the blue light emission at about 410 nm disappeared, which may be due to the defect of zinc vacancy. The emission of the yellow band at about 550 nm was enhanced, which could have originated from the interstitial oxygen. These results indicate that the concentrations or types of the dominant defects could be changed because of the diffusion of Al substrates during the course of annealing. The as-prepared flower-like nanostructures of nanorods exhibited a high UV emission peak (at about 380 nm). After the samples were annealed, the green emission (at about 500 nm) was also enhanced abnormally, except for the UV emission (at 380 nm), indicating that the crystalline quality could not be improved by annealing for complex nanostructures, except for the top of the structures. Our results present a simple, reproducible, and cost-competitive method to synthesize ZnO three-dimensional flower-like structures and would provide useful information for the fabrication of optoelectronic devices at room temperature.

Superhydrophobic and Photocatalytic Synergistic Self-Cleaning Coating Constructed by Hierarchically Structured Flower-like Hollow SiO2@TiO2 Spheres with Oxygen Vacancies.

The self-cleaning coating has both superhydrophobic physical and photocatalytic chemical self-cleaning properties, which has attracted the wide attention of researchers in recent years. First, the flower-like hollow SiO2@TiO2 spheres with oxygen vacancies (rFHSTs) were prepared by the liquid-phase reduction method, in which several different functional components were integrated. Meanwhile, the influence mechanisms of the physical structure and chemical composition on the photocatalytic properties are discussed in detail. The results proved that rFHSTs exhibited the enhanced photoresponse range and photocatalytic degradation performance in visible light because of the synergistic effect of the microstructure (internal cavity, 3D flower-like nanosheet), SiO2/TiO2 heterojunction structure, and oxygen vacancies. After that, superhydrophobic modified rFHSTs were used as fillers to fabricate PVA/PFDTS-rFHSTs composite coatings with both physical and chemical self-cleaning properties. The self-cleaning performances and principles of the composite coating were examined and explored. The results showed that the low surface energy of the hydrophobic chain segment, the inherent particle effect, and the photocatalytic activity of rFHSTs were responsible for the superhydrophobic and photocatalytic effects, finally endowing the composite coating with self-cleaning performance. In short, this study is profound for the development and application of self-cleaning coatings with both physical and chemical performances.

ZIF-67 derived 3D nanocage-shaped FeCoNi layered double hydroxides as an electrocatalyst for improving the performance of LOBs

Layered double hydroxides (LDHs) with unique structure features are regarded as ideal materials for energy storage. Developing highly efficient cathode catalysts is crucial for improving the storage capacity and stability of lithium-oxygen batteries (LOBs). Herein, we proposed a facile solvothermal strategy to prepare different metal molar ratios of trimetallic FeCoNi LDHs using the zeolitic imidazolate framework-67 (ZIF-67) as a template. When the metal molar ratios of Fe/Ni = 1.7, the obtained FeCoNi LDH (FCN-C) exhibits a 3D nanocage-shaped structure with highly ordered flower-like nanosheets on the surface. The well-designed structures exhibit high specific surface areas and abundant mic-mesoporous channels, which are favored for the transport of electrons and ions diffusion. The synergistic effects of FeCoNi LDH components can effectively regulate the electronic structure and deliver striking electrochemical activities. Specifically, the LOBs with FCN-C cathode possess an excellent specific capacity of 17598.5 mAh g−1 at 0.05 mA cm−2. Under 0.05 mA cm−2 with a cutoff capacity of 500 mAh g−1, the LOBs assembled by FCN-C cathode can achieve 213 cycles, and it is much longer than that of other FeCoNi LDHs cathodes. This simple preparation method can provide new insight to design efficient electrocatalysts for energy applications.

In situ lithiation modulation of LiNi0.8Co0.1Mn0.1O2 as bifunctional electrocatalysts for highly efficient overall water splitting

LiNi0.8Co0.1Mn0.1O2 (NCM811) is a common cathode material in lithium-ion batteries (LIBs), and the ever-increasing consumption of large quantities of LIBs raises critical concerns about their recycling. Herein, we propose an in-situ lithiation route to tune the structure and electrocatalytic properties of NCM811 by Li+ intercalation and exfoliation in LIBs. In this strategy, the morphology and microstructure of the lithiated NCM811 can be controlled by a specified discharge voltage. The lithiation modulation effectively converted the large NCM811 particles into many flower-like nanosheets. The resulting nanosheets are interconnected and have a rich porous structure, which is conducive to the complete penetration and diffusion of electrolytes and accelerating the charge transfer rate. Moreover, oxygen vacancies and amorphous regions were induced in the nanosheets to provide more active sites. The novel lithiation-modulated nanosheets demonstrate high activity and bifunctional characteristics for hydrogen evolution reaction (HER) and oxygen evolution reaction (OER). Specifically, the lithiated NCM811 nanosheets demonstrate a low HER overpotential of 58 mV@10 mA cm−2 and OER overpotential of 222@10 mA cm−2. The assembled electrolytic cell for overall water-splitting requires only 1.74 V to reach 100 mA cm−2 with outstanding durability. This work provides a unique strategy for structural modulation of NCM811 cathode in LIBs as high-performance electrocatalysts for water splitting, and demonstrates a high-value recycle of spent LIB electrodes.

In-doped Sn3O4 flower-like nanosheets for efficient visible-light photocatalytic hydrogen production

Improving photocatalytic activity is crucial for promoting photocatalytic hydrogen production. Element doping is a feasible strategy to accelerate carrier separation and migration rate. Herein, a simple one-pot hydrothermal process was used to create In doped Sn3O4 composite photocatalyst. It was demonstrated that the addition of In considerably raises the concentration of oxygen vacancy, which provides more unsaturated active sites, thus regulating the photocatalyst's electronic structure and surface properties, and promoting the carrier migration efficiency. Meanwhile, the light absorption range of samples after doping is redshifted, and the light absorption capacity is enhanced, which effectively improves the photocatalytic activity. Due to this, the optimal sample's average hydrogen production under visible light reached 22.83 μmol g−1 h−1, 4.5 folds more than that of Sn3O4, and shown good stability. This research presents a novel approach for the development of metal oxide photocatalyst with excellent activity and durability.

Efficient Hydrogen Evolution Catalysts Based on Hierarchical Flowerlike NixCo9–xS8 Nanosheets

In terms of the need for a low-carbon economy and alleviating the need for energy security, hydrogen (H2) plays a key role in promoting a sustainable economy because it is clean and efficient. The bottleneck of the hydrogen evolution reaction (HER) can be overcome by developing high-efficiency electrocatalysts. Using a simple solvothermal method, p-NixCo9–xS8 with polyvinylpyrrolidone (PVP) compounds are successfully prepared with synergistic effects between bimetallic sulfides. The resulting p-NixCo9–xS8 catalyst shows a hierarchical flowerlike nanosheet shape based on physical representations. An ultrathin and porous nanosheet surface facilitates rapid electrolyte injection and provides abundant active sites for H+ adsorption, thus giving p-NixCo9–xS8 nanosheets outstanding HER performance. Furthermore, the synergistic effect of a bimetallic electrocatalyst is helpful to improve HER activity. In comparison to NixCo9–xS8 nanosheets without PVP, individual Co9S8 particles, and individual Ni9S8 nanosheets, p-NixCo9–xS8 nanosheets have a lower overpotential (137 mV to 10 mA cm–2), Tafel slope (109 mV dec–1), and 95.7% retention of current after 1000 cycles in the HER process.

Effectively enhanced piezocatalytic activity in flower-like 2H-MoS2 with tunable S vacancy towards organic pollutant degradation

Piezocatalysis technology is emerging as a promising strategy for removing organic pollutants from water by harvesting mechanical energy from the surrounding environment. Herein, 2H-MoS2 flower-like nanosheets with tunable S vacancies was synthesized via a hydrothermal method by adjusting pH of the precursor solution, Mo and S molar ratio, reaction time and temperature. The results showed that the presence of S vacancy leads to significantly enhanced piezoelectric response in the MoS2 nanosheets, as confirmed by both theoretical calculation using first-principle based density functional theory and probe force microscopy (PFM) measurements. As a result, the as-obtained MoS2 nanoflower piezocatalyst exhibited excellent degradation efficiency for Orange Ⅱ solution (removal rate > 95 % in 1 h) under ultrasonic vibration (40 kHz and 110 W). Importantly, we demonstrated for the first time that the piezocatalytic performance was tightly related with the water level in ultrasonic cleaner. The present work not only reports a simple and effective strategy for improving the piezocatalytic degradation activity of MoS2 by introducing vacancy, but also provides new insights and deeper understanding on the underlying mechanism.

In Situ Fabrication of Mn-Doped NiMoO4 Rod-like Arrays as High Performance OER Electrocatalyst

The slow kinetics of the oxygen evolution reaction (OER) is one of the significant reasons limiting the development of electrochemical hydrolysis. Doping metallic elements and building layered structures have been considered effective strategies for improving the electrocatalytic performance of the materials. Herein, we report flower-like nanosheet arrays of Mn-doped-NiMoO4/NF (where NF is nickel foam) on nickel foam by a two-step hydrothermal method and a one-step calcination method. The doping manganese metal ion not only modulated the morphologies of the nickel nanosheet but also altered the electronic structure of the nickel center, which could be the result of superior electrocatalytic performance. The Mn-doped-NiMoO4/NF electrocatalysts obtained at the optimum reaction time and the optimum Mn doping showed excellent OER activity, requiring overpotentials of 236 mV and 309 mV to drive 10 mA cm-2 (62 mV lower than the pure NiMoO4/NF) and 50 mA cm-2 current densities, respectively. Furthermore, the high catalytic activity was maintained after continuous operation at a current density of 10 mA cm-2 of 76 h in 1 M KOH. This work provides a new method to construct a high-efficiency, low-cost, stable transition metal electrocatalyst for OER electrocatalysts by using a heteroatom doping strategy.

A CTAB-assisted PANI-MoS2 nanosheet flower morphology for the highly sensitive electrochemical detection of hydrazine.

In this work, cetyl trimethylammonium bromide (CTAB)-assisted polyaniline-molybdenum disulfide (CPANI-MoS2) nanosheets with a flower morphology have been synthesized through in situ polymerization and a hydrothermal method. The composite was analyzed for structural modification through X-ray diffraction (XRD) to examine chemical changes and the presence of functional groups via Fourier transform infrared (FTIR) and Raman spectroscopy techniques. The surface morphology was identified by field-emission scanning electron microscopy (FESEM) and high-resolution transmission electron microscopy (HR-TEM) techniques. The CPANI-MoS2 nanosheet glassy carbon electrode (GCE) offers a novel strategy for the electrochemical detection of carcinogenic hydrazine. The cyclic voltammetry (CV) curve demonstrated a quasi-reversible behaviour with a high-surface area. Furthermore, differential pulse voltammetry (DPV) analysis of hydrazine detection showed a wide linear range from 10 μM to 100 μM, a low limit of detection of 0.40 μM, and a high sensitivity of 7.23 μA μM cm-2. The determination of hydrazine in a water sample and the recovery percentage were found to be 100.31% and 103.73%, respectively. The CPANI-MoS2 nanosheet GCE significantly contributed to the high electroanalytical oxidation activity due to the CTAB surfactant modifying the flower-like nanosheet morphology, which enables the easy adsorption of hydrazine analyte species and exhibits a high current rate with a rapid detection response.

Electrochemiluminescent system based-on novel semi-sandwich Lanthanide metal complex with 3D rod-like nanoflowers In2O3/ZnIn2S4 as co-reaction accelerator for kanamycin detection

Based-on novel semi-sandwich phthalocyanine(Pc) gadolinium complex as luminophore and three-dimensional flower-like nanorods In2O3/ZnIn2S4 as co-reactant accelerator (CRA), an electrochemiluminescent (ECL) aptasensor with a highly sensitive signal amplification strategy was constructed. The Pc-Gd complex exhibited excellent luminescent property enhanced by "antenna effect" of 18-electron conjugated macrocycle ligand. In addition, the proper design and configuration of In2O3/ZnIn2S4 tubular heterogeneous structure accelerated the transfer of photo-generated charges and the flower-like nanosheets formed provided more active sites, which could not only greatly increase luminophore loading but also effectively shorten transmission distance between ions and co-reactants. The constructed biosensor showed superior kanamycin (KAN) detection performance within 0.01 pg/mL-1000 ng/mL and a detection limit down to 0.003 pg/mL(S/N = 3). The current work developed a new strategy to amplify ECL using lanthanide complex as luminophore and In2O3/ZnIn2S4 as CRA, providing valuable information for the future ECL sensor design and extending the application field of lanthanide luminescent complex.

Heterostructure engineering of self-supported bimetallic sulfide as an efficient bifunctional electrocatalyst for overall water splitting

The exploitation of effective bifunctional electrocatalysts for oxygen and hydrogen evolution reactions (OER, HER) is of great significance to hydrogen energy production via electrocatalytic water splitting. Herein, a self-supported Ni3S2/NiMo2S4-POM/NF hybrid heterostructure with uniform flower-like nanosheets and highly porous for overall water-splitting was synthesized via a scalable hydrothermal method followed by a vulcanization treatment. Significantly, the obtained three-dimensional porous heterostructure with high structural integrity ensures sufficient exposure of active sites and effectively adjusts the electronic structure for faster charge carrier dynamic to achieve enhanced reaction kinetics. The as-prepared Ni3S2/NiMo2S4-POM/NF achieves low overpotentials of 275 and 338 mV to deliver a current density of 100 mA cm−2 for OER and HER. Furthermore, the assembled alkaline electrolyze comprised of Ni3S2/NiMo2S4-POM/NF for both anode and cathode exhibits an appealing voltage of 1.53 V at 10 mA cm−2 with excellent long-term durability, implying notable catalytic activity of Ni3S2/NiMo2S4-POM/NF towards overall water-splitting. This work sheds light on a simple approach for synthesizing highly efficient electrocatalysts for water electrolysis.

CoxMo(1−x)S2 intermixed reduced graphene oxide as efficient counter electrode materials for high-performance dye-sensitized solar cells

In this study, nanocomposite electrocatalysts composed of cobalt molybdenum sulfide flower-like nanosheets intermixed with reduced graphene oxide (CoxMo(1−x)S2/rGO) were prepared by a facile one-step hydrothermal method and were used to prepare counter electrodes (CE) of high-performance dye-sensitized solar cells (DSSCs). The structural and morphological analysis of the nanocomposites were carried out using field emission scanning electron microscopy, micro-Raman, and X-ray photoelectron spectroscopies, which revealed 2-dimensional petal-like nanosheets of the ternary metal sulfides intermixed with the reduced graphene oxide sheets. The DSSCs fabricated using CoxMo(1−x)S2/rGO (CMS-2/rGO) as the counter electrode material exhibited power conversion efficiency (PCE) of 9.04%, which was found to be superior to the PCEs of DSSCs with CEs made of MoS2/rGO (7.56%), CoxMo(1-x)S2 (7.04–7.78%), and conventional Pt (8.72%). The electrochemical measurements showed that the excellent electrocatalytic activity of the CoxMo(1−x)S2/rGO on I3- can be attributed to the expanded active sites, improved charge transfer across the CE, and reduced electrode/electrolyte interface resistance. The facile preparation approach and outstanding catalytic behavior of CoxMo(1−x)S2/rGO indicate that the nanostructured CoxMo(1-x)S2/rGO intermix would be a cost-effective material over the platinum used in the CE of DSSCs.

Nanoflower-like P-doped Nickel Oxide as a Catalytic Counter Electrode for Dye-Sensitized Solar Cells.

Flower-like phosphorus-doped nickel oxide (P-NiO) is proposed as a counter electrode (CE) for dye-sensitized solar cells (DSSCs). The flower-like nickel oxide essentially serves as the matrix for the CE, which is expected to promote a two-dimensional electron transport pathway. The phosphorus is intended to improve the catalytic ability by creating more active sites in the NiO for the catalysis of triiodide ions (I3-) to iodide ions (I-) on the surface of the CE. The P-NiO is controlled by a sequencing of precursor concentration, which allows the P-NiO to possess different features. The debris aggregation occurs in the P-NiO-1, while the P-NiO-0.75 leads to the incomplete flower-like nanosheets. The complete flower-like morphology can be observed in the P-NiO-0.5, P-NiO-0.25 and P-NiO-0.1 catalytic electrodes. The DSSC with the P-NiO-0.5 CE achieves a power conversion efficiency (η) of 9.05%, which is better than that of the DSSC using a Pt CE (η = 8.51%); it also performs better than that with the Pt CE, even under rear illumination and dim light conditions. The results indicate the promising potential of the P-NiO CE to replace the expensive Pt CE.