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Defects in perovskite films not only challenge the efficiency and stability improvement of perovskite solar cells (PSCs), but also serve as electronic dopants that impact interface energetics and charge-transfer kinetics. To address this issue, herein, we introduced a natural additive into a perovskite precursor to improve the inorganic CsPbI2Br film quality. Arising from the strong interaction between passivation molecules and undercoordinated Pb2+ in the perovskite, the reduction in defects results in effective n-type de-doping of the inorganic CsPbI2Br perovskite surface, concomitantly forming an n/n− homojunction at the top perovskite/carbon interface for accelerating charge extraction and suppressing carrier nonradiative recombination in a carbon-based PSC. Consequently, a cutting-edge efficiency as high as 15.0% was achieved with reduced hysteresis in addition to significantly improved long-term stability for a 65 days storage period in the air (94.74% efficiency retention rate) and persistent light irradiation for over 230 hours in N2 (∼82% efficiency retention rate). [ABSTRACT FROM AUTHOR]

In this study, Fe1Pt3 nanoparticles are dispersed on MoS2 nanosheets to integrate the fascinating features of noble metal with highly exposed nanosheets. The MoS2 nanosheets supply good support for the uniform dispersion and easily accessibility of Fe1Pt3 nanoalloys, and ultrafine Fe1Pt3 nanoparticles provide a large number of active sites and enhanced catalysis/charge kinetics. The Fe1Pt3-MoS2 catalyst exhibits good hydrogen evolution performances in acidic media with low overpotential of 59 mV at current density of 10 mA cm−2 and robust catalysis kinetics (Tafel slope of 38 mV dec−1), making it high-efficiency HER catalyst with low Pt loading. [ABSTRACT FROM AUTHOR]

As nonspecific adsorption or biofouling has obvious side effects on the selectivity, it is a great challenge for cytosensors to detect target cells in practical biological samples. In this study, we first propose the design and synthesis of an antifouling photoelectrode. The antifouling photoelectrode not only has the desired photocurrent response, but also possesses an unexpected antifouling capability of resisting nonspecific adsorption of biomolecules. Herein, the PEDOT-HPG/SnS/ZnO-NT antifouling photoelectrode was formed and a robust photoelectrochemical cytosensor with enhanced sensitivity and selectivity has been demonstrated. [ABSTRACT FROM AUTHOR]

The application of metal oxides and sulfides for lithium‐ion batteries (LIBs) is hindered by the limited Li+ diffusion kinetics and inevitable structural damage. Pseudocapacitance for electrochemical lithium storage provides an effective and competitive solution for developing electrode materials with large capacity, high rate capability, and stability. Herein, a composite composed of VS4 nanoplates tightly bound to carbon nanotubes (VS4/CNTs) is developed to demonstrate pseudocapacitance‐assisted lithium storage. The texture of the assembled VS4 nanoplates supplies efficient electrolyte/ion diffusion, as well as exposed surface for pseudocapacitive behavior. The effective coupling between VS4 and CNTs ensures fast electron transfer and high stability. The VS4/CNTs anode exhibits high capacity of 1144 mAh g−1 at 0.1 A g−1, superior cycling stability (capacity retention of 100 % at 1 A g−1 after 400 cycles), and good rate capability. The pseudocapacitive behavior plays an important role in determining the excellent electrochemical properties, contributing to the increased charge rate and reaching as high as 42 % of the total charge at a scan rate of 1 mV s−1. This study demonstrates the potential application of metal sulfides with pseudocapacitive contribution in LIBs. [ABSTRACT FROM AUTHOR]

An efficient signaling on–off mechanism was first proposed by integrating exciton–plasmon coupling and exciton energy transfer into cathodic PEC bioassays. This signaling on–off mechanism has endowed the cathodic PEC biosensor with powerful capability for ultrasensitive and specific detection of target DNA. [ABSTRACT FROM AUTHOR]

The present study reports an aqueous synthesis approach towards off-stoichiometric copper indium sulfide quantum dots with emissions in the near-infrared spectral range. The photoluminescence properties of the dots, and in particular the appearance of dual emission at high Cu deficiency, were studied with temperature-dependent steady-state and transient photoluminescence spectroscopy. [ABSTRACT FROM AUTHOR]

Graphical abstract Highlights • The design of combining photoanode with biocathode was proposed to develop a robust PEC immunosensor. • The TiO 2 -NTs/CIS(1:3)/CIS(1:40) photoanode has evident photocurrent response and good stability. • The PS@Ab 2 conjugates of the biocathode could significantly amplify the photocurrent signal. • The developed PEC immunosensor exhibited both of enhanced sensitivity and specificity. Abstract Highly sensitive and specific detection of biomarkers is of great importance for diagnosis and treatment of the related diseases or cancers. We herein developed a robust photoelectrochemical (PEC) immunosensor with enhanced sensitivity and specificity based on evident photocurrent output of the photoanode and significant signal amplification of the biocathode. Prostate specific antigen (PSA, Ag) was used as a target model to exhibit analytical performances of the designed PEC immunosensor. Two kinds of CuInS 2 quantum dots (CIS QDs) with different composition were modified on the TiO 2 nanotubes (TiO 2 -NTs) electrode to fabricate the photoanode. Due to the co-sensitization effect of the CIS QDs on TiO 2 -NTs, an evident photocurrent output was generated at the photoanode. For the biocathode, Au nanoparticles (AuNPs) and polydopamine (PDA) were modified in order on indium-tin oxide (ITO) electrode to immobilize capture PSA antibody (Ab 1). Carboxyl-modified polystyrene (PS) nanospheres were coated with secondary antibodies (Ab 2) to form PS@Ab 2 conjugates, which were used as signal amplifiers via the specific immunoreaction between Ag and Ab 2. Based on joint action of evident photocurrent output of the photoanode and significant signal amplification of the biocathode, the designed PEC immunosensor exhibited an ultralow detection limit of 3.4 fg/mL for target PSA detection. Meanwhile, it also showed an enhanced specificity owing to the separation of the photoanode and the biocathode. [ABSTRACT FROM AUTHOR]

A general, efficient strategy for a self-powered PEC immunoassay with an evident photocurrent response was proposed by separating the photoanode from recognition events. The immunoassay demonstrates the exciting features of both high sensitivity and anti-interference capabilities. [ABSTRACT FROM AUTHOR]

Solidifying the soft lattice of all‐inorganic mixed‐halide perovskites is of great importance to restrain the notorious halide segregation under persistent light illumination. Herein, a multifunctional columnar macrocyclic molecule additive, namely cucurbituril into perovskite precursor to enhance the crystallization and reduce the defect density in the final perovskite film is introduced. Based on the theoretical calculation and simulation, the cucurbituril molecule with a strong double‐ended negatively‐charged cavity surrounded by terminated oxygen atoms not only coordinates with dangling Pb2+ ions to form host‐guest complexation but also induces an electric dipole field at perovskite grain boundary to effectively repel the iodide ion migration from the inside grain to the defective boundary, significantly suppressing the halide segregation and improving the device performance. As a result, the carbon‐based, all‐inorganic CsPbI2Br solar cell achieves an enhanced efficiency of 15.59% with great tolerance to environmental stresses. These findings provide new insights into the development of a novel passivation strategy with macrocyclic molecules for making high‐efficiency and stable perovskite solar cells. [ABSTRACT FROM AUTHOR]

An electrochemical sensor for paracetamol is described that consists of a glassy carbon electrode (GCE) that was modified with the conducting polymer poly(3,4-ethylenedioxythiophene) (PEDOT) doped with MnO2 nanoflowers. The hydrothermally synthesized MnO2 nanoflowers possess a large surface area and can be doped into PEDOT through electrochemical deposition to form a conducting polymer nanocomposite. The nanoflowers are shown to be uniformly distributed within the nanocomposite as revealed by elemental mapping analysis. The nanocomposite displays excellent catalytic activity toward the electrochemical oxidation of paracetamol. The modified GCE, best operated at a working potential of around 0.37 V (vs. SCE) has a linear response in 0.06 to 435 μM paracetamol concentration range and a very low limit of detection (31 nM at a signal-to-noise ratio of 3). The sensor exhibits excellent reproducibility and stability, and satisfying accuracy for paracetamol detection in pharmaceutical samples. [ABSTRACT FROM AUTHOR]

Solid-state nanochannels have great potentials in the vibrant field of photoelectrochemical (PEC) bioanalysis. This work herein demonstrates the innovative use of DNA-decorated nanoporous anodic alumina (NAA) nanochannels for sensitive PEC bioanalysis of telomerase (TE) activity. Specifically, telomerase primer sequences (TS) were initially immobilized within the NAA nanochannels and then extended by TE in the presence of deoxyribonucleoside triphosphates (dNTPs). The as formed single-strand DNA was then directed to hybrid with many partially matched single-strand assisting DNA (aDNA), leading to the formation of multiple DNAzymes by the unmatched parts and the subsequent DNAzyme-stimulated biocatalytic precipitation (BCP) within the nanochannels. Because the inhibited signals of the photoelectrode could be correlated with TE-enabled TS extension, an innovative nanochannels PEC bioanalysis could be realized for probing TE activity. This work features the ingenious use of DNA-associated nanochannels for PEC bioanalysis of TE activity. Given the versatile functions of DNA molecules, the extension of this strategy easily allows for addressing numerous other targets of interest. Also, we envision this work could inspire more interest for the further development of nanochannels PEC bioanalysis. • An innovative PEC bioanalysis of telomerase activity was proposed based on solid-state nanochannels. • The AgIn 5 S 8 /TiO 2 /ITO photoelectrode exhibited evident photocurrent response and high stability. • Target-induced formation of multiple DNAzymes could evidently amplify the PEC detection signal. • This strategy could be extended easily for building nanochannels PEC bioanalysis toward other targets of interest. [ABSTRACT FROM AUTHOR]

Highlights: [•] Mesoporous Co3O4 octahedra have been prepared with simple sol-gel method. [•] Porous structure buffers the volume change and shortens the diffusion path of Li+. [•] Anisotropy octahedral morphology guarantees structural stability. [•] It exhibits high capacity, superior capacity retention and excellent rate capability. [Copyright &y& Elsevier]

Developing novel catalysts with high efficiency and low cost for electrochemical hydrogen production is of great significance for sustainable energy applications. Herein, we present the exploratory research on nickel foam supported heterostructures of NiCo hydrogen carbonate (Ni 0.6 Co 0.4 (HCO 3) 2) with Pt nanoparticles on the surface for alkaline water hydrogen evolution reaction (HER). The heterogeneous engineering ensures effective synergism of moderate hydrogen adsorption energy, accelerated catalysis kinetics, improved active sites, and enhanced charge transfer, thus inducing excellent HER activity (56 mV at 10 mA cm−2 for geometric area and 15 mV at 10 mA cm−2 for electrochemical surface area) and stable durability. Notably, the mass activity of Pt in Pt–Ni 0.6 Co 0.4 (HCO 3) 2 is even higher than that of Pt/C. This study provides new insights into developing high-efficiency catalysts for hydrogen electrocatalysis, which also demonstrates that hydrogen carbonates are promising alternatives for electrochemical water splitting in addition to the widely focused transition metal hydroxides and oxides. • Ni 0.6 Co 0.4 (HCO 3) 2 is firstly hybridized with Pt for improved HER. • The electronic interaction moderates the hydrogen adsorption energy on Pt. • The intrinsic HER activity is activated. • Improved active sites density and enhanced charge transfer are acquired. • The mass activity of Pt in composite catalyst is higher than that of Pt/C. [ABSTRACT FROM AUTHOR]

• Heterostructure of Ru 2 P particles decorated Ni 2 P nanosheets is prepared. • Synergism induces accelerated kinetics and intrinsic activity. • Improved active sites density and enhanced charge transfer are obtained. • Showing robust activity and stability for HER in wide pH range. Lacking efficient and pH-universal catalysts is currently the main obstacle for the large-scale production of hydrogen through electrochemical water splitting. The hetero material of Ru 2 P nanoparticles and Ni 2 P nanosheets is constructed on carbon fiber cloth as pH-tolerant catalyst for hydrogen generation. The designed heterointerface provides synergism and structure advantages for improved intrinsic catalysis activity, more accessible active sites, and enhanced charge transfer for hydrogen evolution. The electrochemical measurements demonstrate the active hydrogen production properties, such as low overpotentials (46 mV, 47 mV, and 51 mV in 0.5 M H 2 SO 4 , 1 M KOH, and 1 M phosphate-buffered saline, respectively) at a current density of 10 mA cm−2, as well as rapid catalysis kinetics with small Tafel slopes and good stability. [ABSTRACT FROM AUTHOR]

An efficient but general strategy for antifouling photoelectrochemical cytosensor was proposed by introducing zwitterionic peptide. The cytosensor demonstrated the distinct merits of high sensitivity and low fouling in the biological media. • Zwitterionic peptide as antifouling material was first introduced in PEC biosensor. • The ITO/TiO 2 /ZnIn 2 S 4 electrode as PEC matrix had evident photocurrent response and good stability. • The PEC cytosensor exhibited high sensitivity and good antifouling capability in the biological media. • The application of antifouling biomaterials is a promising way to resist nonspecific adsorption or biofouling. Resulting from nonspecific adsorption or obvious biofouling, target detection in real biological media is a potential challenge for most of the biosensors. Herein, we first report an antifouling photoelectrochemical (PEC) cytosensor by using zwitterionic peptide. The typical cervical carcinoma Henrietta Lacks (HeLa) cell was chosen as a target model and the aptamer AS1411 was used as its recognition element. TiO 2 nanoparticles (NPs) and ZnIn 2 S 4 nanocrystals (NCs) were modified in order on a bare indium–tin oxide (ITO), forming ITO/TiO 2 /ZnIn 2 S 4 electrode as the PEC matrix to immobilize aptamer AS1411 and zwitterionic peptide. The fabricated PEC cytosensor exhibited a high sensitivity toward HeLa cell detection, with the detection limit of 34 cells/mL. Besides, owning to excellent antifouling property of the zwitterionic peptide, evidently reduced nonspecific adsorption of the cytosensor was realized in the biological media. [ABSTRACT FROM AUTHOR]