diff --git a/tests/test_notebooks.py b/tests/test_notebooks.py
index 750dc35169..bc005f2201 100644
--- a/tests/test_notebooks.py
+++ b/tests/test_notebooks.py
@@ -12,7 +12,7 @@
 
 @pytest.fixture()
 def common_kwargs(tmp_path):
-    outputnb = tmp_path.join('output.ipynb')
+    outputnb = tmp_path.joinpath('output.ipynb')
     return {
         'output_path': str(outputnb),
         'kernel_name': f'python{sys.version_info.major}',