Self-supporting electrocatalyst constructed from in-situ transformation of Co(OH)2 to metal-organic framework to Co/CoP/NC nanosheets for high-current-density water splitting.

Transition metal phosphide (TMP) emerges as a promising electrocatalyst for overall water splitting (OWS). However, conventional TMP materials require exogenous metal ions to participate in coordination reactions, which usually suffer from active site blocking, pronounced intrinsic impedance, and inevitable catalyst shedding at high current density. Herein, a novel in-situ construction strategy has been developed to grow N-doped carbon (NC) enwrapped Co/CoP nanosheets directly onto Co foam (abbreviated as CoF) through a three-step transformation of Co to Co(OH)2 to Co-Metal-Organic Framework (Co-MOF) to Co/CoP/NC. In the entire preparation process, Co metal is only provided by the CoF substrate without external metal sources. Such in-situ construction yields tight contact at the interface of the heterogeneous catalyst, leading to much-reduced impedance and boundary vacancy, while the porous nitrogen-doped carbon backbone further endows the catalyst with the exposure of massive active sites, promotes mass transfer, and possesses high electrical conductivity. The Co/CoP/NC/CoF requires overpotentials of only 64 mV/263 mV@10 mA cm-2 and 414 mV/481 mV@400 mA cm-2 for both HER/OER in 1.0 M KOH, respectively. Remarkably, it reveals excellent OWS catalytic activity with a cell voltage of 1.56 V@10 mA cm-2 and 1.88 V@200 mA cm-2. This strategy of in-situ interface engineering transformation provides new ideas for direct device processing and construction of highly-efficient transition-metal-based OWS electrode materials.

[Roles of Programmed Cell Death-1/Programmed Cell Death-ligand 1 and Cytotoxic T-lymphocyte-associated Protein 4 Signaling Pathways in Bladder Urothelial Carcinoma].

Bladder urothelial carcinoma(BUC)is a common malignant tumor in the urinary system.Pt-based chemotherapy has long been a standard therapeutic method for resectable or metastatic BUC,but with poor outcomes.Immune checkpoint inhibitors specific to programmed death 1(PD-1)/programmed death-ligand 1(PD-L1)and cytotoxic T lymphocyte-associated protein 4(CTLA-4)pathways have shown significant antitumor activities,safety,and enduring reactivity in clinical trials,thus creating a new epoch for the treatment of advanced-stage BUC.This article reviews the relationships of BUC with PD-1/PD-L1 and CTLA-4 pathways,as demonstrated in clinical trials.In particular,the authors elucidate the clinical studies on the application of immune checkpoint inhibitors in different BUC stages and their optimal combining strategies,with an attempt to improve the clinical use of immune inhibitors for BUC treatment.